Associations between daytime napping, sleep duration, and depression and 15 cardiovascular diseases: a Mendelian randomization study
Original Article

Associations between daytime napping, sleep duration, and depression and 15 cardiovascular diseases: a Mendelian randomization study

Yilin Li1, Parveen K. Garg2, Jing Wu1

1Department of Geriatrics, The Third People’s Hospital of Chengdu, Chengdu, China; 2Division of Cardiology, University of Southern California Keck School of Medicine, Los Angeles, CA, USA

Contributions: (I) Conception and design: All authors; (II) Administrative support: All authors; (III) Provision of study materials or patients: Y Li; (IV) Collection and assembly of data: Y Li; (V) Data analysis and interpretation: Y Li; (VI) Manuscript writing: All authors; (VII) Final approval of manuscript: All authors.

Correspondence to: Jing Wu, BM. Department of Geriatrics, The Third People’s Hospital of Chengdu, 82 Qinglong Street, Qingyang District, Chengdu 610031, China. Email: wjing0103@163.com.

Background: Numerous studies have documented the effects of daytime napping, sleep duration, and depression on cardiovascular diseases (CVDs). However, the evidence has been gleaned from observational studies that might be riddled with confounding variables and the possibility of reverse causation bias. Therefore, the present study employed a Mendelian randomization (MR) methodology to meticulously explore the relationships between daytime napping, sleep duration, and depression, and the risk profiles of CVDs.

Methods: Genome-wide significant genetic variants associated with daytime napping, sleep duration, and depression were used as the instrumental variables (IVs). Data on the genetic correlations between these IVs and 15 CVDs were derived from the United Kingdom (UK) Biobank, Finnish Genome Studies, and other large-scale collaborations. We conducted both univariate and multivariate MR analyses to assess the overall effects and mediated relationships after adjusting for potential confounders, including body mass index (BMI), smoking status, and type 2 diabetes. The effect sizes were estimated using inverse variance-weighted (IVW) regression.

Results: The MR analysis revealed that an increased risk of heart failure (HF) [odds ratio (OR): 1.366; 95% confidence interval (CI): 1.013–1.842; P=0.04], coronary atherosclerosis (OR: 1.918; 95% CI: 1.257–2.927; P=0.003), myocardial infarction (MI) (OR: 1.505; 95% CI: 1.025–2.211; P=0.04), and coronary artery disease (CAD) (OR: 1.519; 95% CI: 1.130–2.043; P=0.006) was significantly associated with genetically predicted daytime napping. Prolonged sleep duration was found to be related to a reduced risk of HF (OR: 0.995; 95% CI: 0.993–0.998; P=2.69E−04), peripheral vascular disease (PVD) (OR: 0.984; 95% CI: 0.971–0.997; P=0.02), and CAD (OR: 0.997; 95% CI: 0.994–0.999; P=0.006). Additionally, a statistically significant positive relationship was observed between depressive disorders and the occurrence of atrial fibrillation (AF) (OR: 1.298, 95% CI: 1.065–1.583, P=0.01), indicating a heightened susceptibility. The multivariable MR analyses substantiated the reliability of the observed associations between daytime napping and the incidence of HF and CAD, following adjustments for genetically predicted BMI and smoking. The sensitivity analysis did not reveal any evidence of horizontal pleiotropy or heterogeneity, thus supporting the validity of the study’s results.

Conclusions: This MR investigation posits a potential causal nexus between daytime napping, sleep duration, and depression, and the genesis of CVDs, offering new perspectives on the prevention and management of CVDs.

Keywords: Daytime napping; sleep duration; depression; cardiovascular diseases (CVDs); Mendelian randomization (MR)


Submitted Jul 02, 2024. Accepted for publication Sep 13, 2024. Published online Oct 15, 2024.

doi: 10.21037/cdt-24-313


Highlight box

Key findings

• Daytime napping, sleep duration, and depression are strongly associated with the development of cardiovascular diseases (CVDs), providing new perspectives on CVDs prevention and management.

What is known and what is new?

• Numerous studies have documented the effects of daytime napping, sleep duration or depression on CVDs.

• This two-sample Mendelian randomization (MR) analysis revealed that daytime napping and depression were positively associated with several CVDs. Conversely, a genetic predisposition to a longer sleep duration was linked to reduced risks of several CVDs.

What is the implication, and what should change now?

• The management of daytime napping, adequate sleep duration, and depression have the potential to prevent CVDs, among which body mass index, smoking and type 2 diabetes play an intermediary role.


Introduction

Cardiovascular disease (CVD) represents the predominant contributor to global morbidity and mortality (1,2). In 2020, CVDs were responsible for an estimated 19 million fatalities worldwide, representing a substantial increase of 18.7% from the figures documented in 2010 (3). Despite significant advancements in preventive strategies, the etiological factors underlying CVD remain incompletely understood (2,4). Consequently, elucidating the risk factors associated with CVD development is essential for the refinement of preventive practices and strategies.

Numerous studies have documented the effects of sleep characteristics, including daytime napping and sleep duration on CVDs (5-7). Nonetheless, the correlation between daytime napping or sleep duration and the onset of CVDs remains equivocal. Various investigations have suggested that daytime napping may be a contributory factor to the development of hypertension (8-10), stroke (11), coronary artery disease (CAD) (12-14), and heart failure (HF) (15). Conversely, some studies have posited that napping during the daytime could potentially provide a protective benefit against the development of hypertension (10,16,17), CAD (18,19), and HF (19). In addition, it has been suggested that prolonged sleep duration may elevate the risk of atrial fibrillation (AF) development (20-23). Additionally, several studies have uncovered a link between short sleep duration and extended daytime napping, exceeding one hour, and an increased risk of depression (24,25). Notably, there is evidence of a link between depression and sleep quality (24,26,27), which in turn could heighten the risk of CVDs (28-36). Nonetheless, the causal nature of these associations remains uncertain, as a considerable amount of the evidence has been gleaned from observational studies that might be riddled with confounding variables and the possibility of reverse causation bias.

With the advent of genome-wide association studies (GWASs), the technique of Mendelian randomization (MR) analysis has seen a surge in usage (37). MR is a method that employs genetic variations as instrumental variables (IVs) to evaluate the causal effects of associations between an exposure and an outcome (38). Relative to observational studies, genetic variants are randomly allocated at the time of conception, which diminishes the probability of confounding influences (39). Additionally, this strategy significantly reduces the risk of reverse causation, as it operates on the principle that germline phenotypes are intrinsic and cannot be altered by subsequent disease states (40,41). In this article, we present a MR study that sought to assess the causal relationship between daytime napping, sleep duration, and depression, and 15 CVDs. To elucidate the potential mechanisms, we proceeded to perform a multivariate MR analysis to scrutinize the mediating roles of body mass index (BMI), smoking, and type 2 diabetes. We present this article in accordance with the STROBE-MR reporting checklist (available at https://cdt.amegroups.com/article/view/10.21037/cdt-24-313/rc).


Methods

Study design and data sources

We conducted a two-sample MR analysis to determine the causal effects of three exposures (i.e., daytime napping, sleep duration, and depression) on the following 15 CVDs: HF, hypertension, stroke, AF, arrhythmia, conduction disorders, coronary atherosclerosis, myocardial infarction (MI), non-ischemic cardiomyopathy, non-rheumatic valve diseases, pulmonary embolism, aortic aneurysm, dissection of aorta, peripheral vascular disease (PVD), and CAD. Figure 1 provides a comprehensive overview of the study design. Our MR method is based on the following three basic assumptions: (I) the genetic variants are closely related to daytime napping, sleep duration, and depression (Assumption 1); (II) the genetic variants are not related to other confounders (Assumption 2); and (III) the genetic variants are only related to the clinical outcome through daytime napping, sleep duration, and depression (Assumption 3) (Figure 2). The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). The specific studies and data sets used for the MR analyses are detailed in Table 1.

Figure 1 Study design. SNPs, single nucleotide polymorphisms; MR, Mendelian randomization; MR-PRESSO, Mendelian randomization pleiotropy residual sum and outlier; CAD, coronary artery disease.
Figure 2 An illustrative diagram of the Mendelian randomization assumptions. SNPs, single nucleotide polymorphisms; CVDs, cardiovascular diseases.

Table 1

Information of included studies and consortia

Exposure/mediator/outcome Consortium/first author Population Participants Web source/PubMed ID
Exposure
   Daytime napping UK Biobank European 452,633 individuals https://www.ukbiobank.ac.uk/
   Sleep duration UK Biobank European 10,102 cases and 81,204 controls https://www.ukbiobank.ac.uk/
   Depression UK Biobank European 27,568 cases and 457,030 controls https://www.ukbiobank.ac.uk/
Mediator
   Body mass index UK Biobank European 806,384 individuals https://www.ukbiobank.ac.uk/
   Smoking UK Biobank European 311,629 cases and 321,173 controls https://www.ukbiobank.ac.uk/
   Type 2 diabetes UK Biobank European 38,841 cases and 451,248 controls https://www.ukbiobank.ac.uk/
Outcome
   Heart failure HERMES Consortium European 47,309 cases and 930,014 controls https://www.hermesconsortium.org/
   Hypertension NHGRI-EBI Catalog Hispanic or Latin American 11,863 cases and 8,663 controls https://www.ebi.ac.uk/gwas/
   Stroke Malik R European 40,585 cases and 406,111 controls 29531354
   Atrial fibrillation Nielsen JB European 60,620 cases and 970,216 controls 30061737
   Arrhythmia Dönertaş HM European 7,207 cases and 477,391 controls 33959723
   Conduction disorders The FinnGen study European 4,416 cases and 156,711 controls https://www.finngen.fi/fi
   Coronary atherosclerosis The FinnGen study European 23,363 cases and 187,840 controls https://www.finngen.fi/fi
   Myocardial infarction The FinnGen study European 20,917 cases and 440,906 controls https://www.finngen.fi/fi
   Non-ischemic cardiomyopathy The FinnGen study European 11,400 cases and 175,752 controls https://www.finngen.fi/fi
   Non-rheumatic valve diseases The FinnGen study European 10,235 cases and 156,711 controls https://www.finngen.fi/fi
   Pulmonary embolism The FinnGen study European 4,185 cases and 214,228 controls https://www.finngen.fi/fi
   Aortic aneurysm The FinnGen study European 3,230 cases and 475,964 controls https://www.finngen.fi/fi
   Dissection of aorta The FinnGen study European 470 cases and 206,541 controls https://www.finngen.fi/fi
   Peripheral vascular disease The FinnGen study European 1,037 cases and 206,541 controls https://www.finngen.fi/fi
   Coronary artery disease CARDIoGRAMplusC4D European 122,733 cases and 424,528 controls http://www.cardiogramplusc4d.org/

IV selection

To select the IVs, the following rigorous three-step methodology was adopted: (I) the single nucleotide polymorphisms (SNPs) that met the genome-wide significance threshold of P<5×10−8 were selected; (II) corresponding linkage disequilibrium (LD) was used to identify the SNPs in a LD state. We ensured the independence of the SNPs by excluding those within a 10,000-kb window by applying a r2 threshold of <0.001; (III) the efficacy of the individual SNPs was affirmed by a F-statistic evaluation. The SNPs with F-statistics >10 were considered robust and credible IVs, which protected the MR outcomes against the potential skewing effects of weak instrument bias (42,43). Comprehensive details regarding the SNPs employed are provided in Tables S1-S3.

Data sources for three exposures

GWAS summary statistics for daytime napping, sleep duration, and depression were obtained from the United Kingdom (UK) Biobank (44). The daytime napping GWAS data comprised a substantial cohort of 452,633 individuals of European descent (45). The sleep duration GWAS data comprised 10,102 cases and 81,204 controls (46). Genetic variants exhibiting LD (as characterized by a r2 value >0.01 or clump distance <10,000 kilobases) and those demonstrating a less significant correlation to the exposure of interest were systematically excluded. Following this filtration process, 49 independent SNPs were retained as IVs for the analysis of daytime napping, 78 for sleep duration, and 98 for depressive symptoms. The summary data set for depression comprised 27,568 cases and 457,030 controls (Table 1).

Data sources for CVD diseases

For the dependent variables under investigation, the aggregated data for HF (comprising 47,309 affected individuals and 930,014 unaffected controls), hypertension (comprising 11,863 affected individuals and 8,663 controls), conduction disorders (comprising 4,416 affected individuals and 156,711 controls), coronary atherosclerosis (comprising 23,363 affected individuals and 187,840 controls), MI (comprising 20,917 affected individuals and 440,906 controls), non-ischemic cardiomyopathy (comprising 11,400 affected individuals and 175,752 controls), non-rheumatic valve diseases (comprising 10,235 affected individuals and 156,711 controls), pulmonary embolism (comprising 4,185 affected individuals and 214,228 controls), aortic aneurysm (comprising 3,230 affected individuals and 475,964 controls), aortic dissection (comprising 470 affected individuals and 206,541 controls), PVD (comprising 1,037 affected individuals and 206,541 controls), and CAD (comprising 122,733 affected individuals and 424,528 controls) were systematically obtained from respective large-scale GWASs (see Table 1) (47-51). The definition of each outcome has been listed in the Appendix 1. Summary statistics representing the data sets for stroke (comprising 40,585 affected individuals and 406,111 unaffected controls), AF (comprising 60,620 affected individuals and 970,216 controls), and arrhythmia (comprising 7,207 affected individuals and 477,391 controls) were derived from GWASs conducted by Malik et al. (52), Nielsen et al. (53), and Dönertaş et al. (54), respectively. CVD existed concomitantly at baseline.

Data sources for possible mediators

A multivariable MR (MVMR) analysis was conducted to account for the putative confounding factors, including BMI, smoking status, and type 2 diabetes mellitus. These three variables were chosen for inclusion in the analysis, as they have previously been identified as factors significantly correlated with an extensive array of cardiovascular pathologies in prior MR investigations (55-57). At the same time, it is also related to sleep duration, daytime napping, and depression (49,58). Consequently, these factors were considered candidates for mediation. The genetic IVs for BMI, smoking behavior, and type 2 diabetes mellitus were sourced individually from the UK Biobank (for further details and information, see Table 1).

Statistical analysis

The initial analysis incorporated both random-effect and fixed-effect inverse variance-weighted (IVW) MR techniques to estimate the causal effects. The horizontal pleiotropy of the selected SNPs was appraised using the MR-Egger method and the weight median approach. The Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO) technique was used to identify outliers exhibiting horizontal pleiotropy and compensate for their influence. The variability in the estimates derived from the SNPs was assessed using Cochran’s Q statistic. Additionally, a leave-one-out sensitivity analysis was conducted to ascertain if any individual SNP significantly affected the findings. The effects of daytime napping, sleep duration, and depression on the occurrence of CVDs were quantified as the odds ratio (OR) accompanied by the corresponding 95% confidence interval (CI). The robustness of the IVs was evaluated by calculating the F-statistic, with a value >10 indicating sufficient strength. Further, to detect any false positive findings due to multiple comparisons, the Bonferroni correction technique was applied. Power analysis was performed using an online tool (59). In this study, a relationship was considered to have a suggestive level of statistical significance if it had a nominal P value <0.05, and an adjusted P value >0.05 following the Benjamini-Hochberg procedure. All the statistical analyses conducted in this study were performed using the TwoSampleMR and MR-PRESSO packages within R software (version 4.3.1).


Results

Both random and fixed-effects IVW models were used, and through two-sample MR analyses employing these SNPs as IVs, we revealed the causal associations between daytime napping, sleep duration, and depression with the genetically predicted risk of CVDs (Figures 2-4 and Table S4). The results of the MVMR analyses, which took into account various mediators by way of adjustments, are presented in Tables S5-S7. Most associations were well powered (Table S4). For daytime napping, sleep duration, and depression, there was 80% power to detect the smallest OR ranging from 0.651 to 2.076, 0.984 to 1.012, and 0.573 to 1.976 for included outcomes. Although power was lower for sleep duration, it was adequate to detect a moderate effect size for most common CVD.

Figure 3 Associations between a genetic predisposition to daytime napping, and cardiovascular diseases. OR, odds ratio; CI, confidence interval.
Figure 4 Associations between a genetic predisposition to sleep duration and cardiovascular diseases. OR, odds ratio; CI, confidence interval.

Daytime napping and CVD

The genetic predisposition to daytime napping was found to be significantly associated with an increased likelihood of HF (OR: 1.366; 95% CI: 1.013–1.842; P=0.04), coronary atherosclerosis (OR: 1.918; 95% CI: 1.257–2.927; P=0.003), MI (OR: 1.505; 95% CI: 1.025–2.211; P=0.04), and CAD (OR: 1.519; 95% CI: 1.130–2.043; P=0.006) (Figure 3). After adjusting for BMI, the causal effect of daytime napping demonstrated continued significance in relation to HF (OR: 1.379; 95% CI: 1.026–1.853; P=0.04) and CAD (OR: 1.676; 95% CI: 1.256–2.237; P=4.52E−04) (Table S5). In the MVMR analysis, which accounted for the genetically predicted effects of smoking, an association was found between a genetic propensity for daytime napping and a heightened risk of HF (OR: 1.353; 95% CI: 1.038–1.763; P=0.03) and CAD (OR: 1.381; 95% CI: 1.058–1.801; P=0.02). After adjusting for the three aforementioned mediating factors, the causal association between the practice of daytime napping and the risk of CAD (OR: 1.466; 95% CI: 1.083–1.986; P=0.01) remained statistically significant. After adjusting for smoking, there was a negative correlation between daytime napping and non-rheumatic valvular diseases (OR: 0.592; 95% CI: 0.363–0.965; P=0.04).

Sleep duration and CVD

The MR analysis showed that a longer sleep duration was associated with a decreased risk of developing HF (OR: 0.995; 95% CI: 0.993–0.998, P=2.69E−04), PVD (OR: 0.984; 95% CI: 0.971–0.997, P=0.02), and CAD (OR: 0.997; 95% CI: 0.994–0.999, P=0.006) (Figure 4). After adjusting for genetically predicted BMI (OR: 2.474; 95% CI: 1.219–5.021; P=0.01) and considering the combined effect of the three mediators (OR: 2.325; 95% CI: 1.157–4.675; P=0.02), the genetic predisposition to a longer sleep duration showed a more pronounced positive association with the risk of HF (Table S6). After adjusting for smoking, sleep duration was associated with a increased risk of developing stroke (OR: 6.526; 95% CI: 1.768–24.086; P=0.005). After adjusting for type 2 diabetes, sleep duration still had a protective effect on the causal influence of PVDs (OR: 0.011; 95% CI: 0.000–0.467; P=0.02). However, after adjusting for smoking, sleep duration became a risk factor for PVD (OR: 191.403; 95% CI: 1.561–23,472.847; P=0.03).

Depression and CVD

Depression was positively related to AF (OR: 1.298; 95% CI: 1.065–1.583, P=0.01) (Figure 5). However, the causal association between depression and AF attenuated to null after adjusting for BMI, smoking, and type 2 diabetes. In this study, when the causal effect of depression on HF was assessed, the association was weakened but remained positive after adjusting for BMI (OR: 6.727; 95% CI: 1.010–44.820; P=0.05) and a combination of the three mediators (OR: 6.991; 95% CI: 1.040–47.010; P=0.05). However, after accounting for the effect of smoking, the association was weakened and became negative (OR: 0.023; 95% CI: 0.001–0.655; P=0.03) (Table S7). After adjusting for the three mediators, the study found that depression was significantly associated with a heightened risk of conduction disorders (OR: 95.880; 95% CI: 1.478–6,218.371; P=0.03), coronary atherosclerosis (OR: 20.179; 95% CI: 1.512–269.360; P=0.02), and CAD (OR: 1.185; 95% CI: 1.055–1.332; P=0.004). According to the MVMR analysis, after adjusting for type 2 diabetes, depression was significantly associated with an elevated risk of both arrhythmia (OR: 1.097; 95% CI: 1.017–1.183; P=0.02) and MI (OR: 95.233; 95% CI: 1.548–5,858.572; P=0.03).

Figure 5 Associations between a genetic predisposition to depression and cardiovascular diseases.

Sensitivity analysis

The outcomes of the sensitivity analyses were consistent (Table S4). Figures S1-S3 display scatter diagrams illustrating the associations between daytime napping, sleep duration, depression, and the incidence of CVDs, revealing analogous patterns in the data. The leave-one-out sensitivity analysis suggested that the association between daytime napping, sleep duration, depression, and CVDs were robust and not reliant on any individual SNP (Figures S4-S6). The relationships between individual genetic variants and their associations with daytime napping, sleep duration, depression, and CVD risk are delineated in Figures S7-S9. The MR-PRESSO detection identified one to four outliers in the analysis. The findings following the exclusion of these outliers were found to be in alignment with the initial findings in all instances with significant results (Table S4).

The predisposition to daytime napping, as influenced by genetics, was significantly correlated with increased BMI levels (Table S8). The data did not reveal any association between BMI, smoking, type 2 diabetes, and sleep duration (Table S9). However, there was a significant genetic propensity to depression that was correlated with an increased risk of smoking (Table S10).


Discussion

This study undertook a thorough examination of the causal effects of daytime napping, sleep duration, and depression on an array of CVDs. We used a two-sample MR analysis, leveraging extensive GWAS data to draw our conclusions. Our findings indicate that daytime napping was correlated with an increased risk of HF, coronary atherosclerosis, MI, and CAD. Conversely, sleep duration was found to be linked to a reduced risk of HF, PVD, and CAD. Additionally, depression was positively correlated with AF.

Consistent with previous findings, the MR analysis showed that the genetic prediction of daytime napping was related to an increased risk of HF (15,19,57,60,61). However, others find that taking a nap during the day is beneficial (61-63). Failure to take into account the frequency of daytime napping could explain these inconsistent results (61). Unfortunately, most of these previous studies are based on self-reports, which may be unreliable, especially among the elderly, who may not have an accurate description of their nap habits due to cognitive disabilities (64,65). Studies have shown that waking up from a daytime napping leads to excessive sympathetic activation, which can result in an escalated heart rate and elevated blood pressure levels (66-68). The physiological response of a heightened heart rate and elevated blood pressure on waking could inflict additional strain on blood vessels and amplify the demand for oxygen by the heart muscle. Such changes are of particular concern, as they can significantly contribute to the development or exacerbation of HF (15,60,69-76). Our MR analysis results provided evidence that daytime napping has a causal link to a heightened risk of developing coronary atherosclerosis. These findings are in alignment with those of previous research studies (15,57,77). Daytime napping can disturb the sleep cycle, lead to an imbalance in hormone secretion related to the sleep-wake cycle disorder, induce the increase of inflammatory factors in the blood, and thus increase the risk of coronary atherosclerosis (15,74,78,79). A study has shown that health screenings of people at risk for daytime napping habits could be improved to help in the diagnosis and treatment of coronary atherosclerosis (57). The MR analyses shows that daytime napping did not show significant associations with non-rheumatic valvular disease. However, daytime napping plays a significant protective role in preventing the development of non-rheumatic valvular disease when adjusting for smoking. To our best knowledge, the present study may be the first time to assess daytime napping as a causal risk factor for non-rheumatic valvular disease. Therefore, further large intervention trial is needed to explore the effect of daytime napping on non-rheumatic valvular disease.

Consistent with the results of our study, a number of studies have revealed that sleep duration plays a significant protective role in preventing the development of HF (57,60,80,81). Additionally, findings from various studies have reported a correlation between genetically predicted shorter sleep durations and an elevated risk of HF (45,60,82-87). There are several mechanisms to explain the relationship between sleep duration and HF. Sleep restriction can increase sympathetic nerve activity, which in turn can lead to CAD and hypertension, all of which are important risk factors for HF (88). In addition, research has shown that short sleep duration may lead to hypoxia and more severe cardiac dysfunction (72,89). While the association between sleep duration and HF reached statistical significance, it is not quite evident whether it reaches clinical significance given the ORs presented. The OR value of sleep duration to HF is relatively small, which shows that it has little protection for him. The results of this OR value are similar to the original research papers, both of which show that the OR value is small (90). It may be due to the limitations of sample size or statistical methods. Therefore, further large intervention trial is needed to explore the effect of sleep duration on HF. The MR analyses conducted substantiated an inverse relationship between sleep duration and the prevalence of PVD. These findings are consistent with a previous study (91). Further, research has indicated a significant connection between short durations of sleep and the likelihood of developing PVD (91). Short sleep duration may lead to hyperactivity of the sympathetic nerve, an increased inflammatory reaction and oxidative stress, and damage the activity of the coagulation system, thus increasing the risk of PVD (92-94). Short sleep time may also change the circulating levels of leptin and ghrelin (95,96), thus increasing the risk of obesity (96,97) by increasing appetite and calorie intake and reducing energy consumption (97,98), leading to hypertension (99), impaired glycemic control (100), and endothelial dysfunction (101), and thus increasing the risk of PVD. Moreover, results from various meta-analyses have indicated a link between a shorter sleep duration and an increased risk of several health conditions, such as obesity, hypertension, and type 2 diabetes. These conditions are recognized as significant risk factors for PVD (91,102). However, a massive OR is reported for the relationship between prolonged sleep duration and PVD when adjusting for smoking. Numerous studies show that there is a correlation between smoking and PVD (103,104). Some studies have shown that there is a dose correlation between smoking and PVD (105,106). It has been suggested that smoking causes PVD in association with leukocyte and platelet activation, increased inflammatory molecules, vasodilatory dysfunction, smooth muscle proliferation, and increased prothrombotic factors (107,108). In line with our observations, one study has shown that sleep duration exerts a significant protective effect on CAD (82). Previous studies have shown that the genetic prediction of short sleep duration increases the risk of CAD (5,19,82,109-113). Short sleep duration promotes the secretion of inflammatory mediators (93,114) and impels cortisol secretion (115), which activate chronic inflammation (116) and lead to endothelial dysfunction (117,118), increasing the risk of vascular damage (118) and atherosclerosis (119-121). The MR analyses shows that sleep duration did not show significant associations with stroke, which was similar to a previous study (90). However, the relationship between a longer sleep duration and increased stroke risk when adjusting for smoking status appears to be greater in magnitude of effect. Previous MR analyses provided genetic support for a causal relationship between smoking and stroke (122,123). Evidence from observational studies shows that smoking increases the risk of stroke (124). Smoking may increase the risk of stroke through platelet activation, endothelial dysfunction, inflammation, thrombosis and increased coagulation (125). In addition, nicotine may decrease cerebral blood flow (125). The MR analysis showed that a longer sleep duration was associated with a decreased risk of developing HF, PVD, and CAD. However, the impact of sleep duration may not necessarily be linear. Too long sleep duration may rather be harmful. For older adults with HF, previous study revealed that longer sleep durations of ≥8 hours indicates an increase in the risk of cognitive frailty (126,127). For patients with CAD, longer sleep duration is independently related to higher all-cause mortality (128). Moreover, a large amount of evidence from observational studies supports the link between long sleep duration and the risk of CAD (129-131). A number of confounding factors may influence the association between sleep duration and CVDs (132-135). Thus, the significant correlation between long sleep duration and CVD observed in many observational studies may be confounded by these unmeasured factors, and reflect a potential reverse causality. Therefore, further large-scale intervention experiments are needed to explore the influence of sleep duration and CVD, and subgroups of different sleep duration groups should be analyzed in the future.

The MR analysis suggested that depression was positively related to AF. The presence of depression or depressive symptoms has been shown to be associated with an elevated relative risk for AF (10,26,136,137). Similarly, patients with depression are at risk of new-onset AF, and the risk of AF increases further after repeated episodes of depression (137,138). It has been hypothesized that increased levels of acute phase reactants, including pro-inflammatory cytokines, and C-reactive protein, in individuals with depression (139), and heightened angiotensin II through the activation of the renin-angiotensin-aldosterone system, contribute to atrial fibrosis and heightened intra-cardiac pressure. These factors may exacerbate susceptibility to AF (140). In addition, increased sympathetic nerve activity and its arrhythmogenic effects can lead to AF (140). It should be noted that patients with depression exhibited a reduction in cerebral blood flow compared to individuals in a healthy control group (141). This finding suggests that the hemodynamic alterations experienced during AF could be a contributing factor to the observed connection between AF and depression, which offers insight into the underlying mechanism linking the two conditions (137). Indeed, it has been observed that patients with persistent or permanent AF may experience more significant cerebral perfusion deficits than those with paroxysmal AF alone (137). The MR analyses shows that depression did not show significant associations with HF. However, the relationship between depression and HF reverse when adjusting for smoking. This MR analyses did not support previous finds from some observational studies, which showed that smoking has been associated with a higher risk of HF (142-145). In addition, due to reverse causality and confounding, observational studies are prone to bias and may lead to unreliable causal effects. Therefore, further large-scale intervention experiments are needed to explore the influence of depression and smoking on HF. Moreover, in the previous literature, the presence of depression had a negative impact on a variety of CVD, instead of AF alone. Gloria Hoi-Yee Li et al. revealed that depression was associated with increased risk of incident stroke and MI (26). This is inconsistent with our findings. It may be related to inconsistencies in sample size and research methods. Further research is needed to clarify the potential link between depression and CVD.

Our study is distinguished by several methodological strengths. Paramount among these is the use of a MR study design, which markedly reduced the likelihood of biases typically associated with observational research, thereby bolstering the credibility of our results. Additionally, our study probed potential mediating pathways through the application of multivariate MR analyses. This approach not only elucidates the mechanistic links but also serves to inform and guide future clinical interventions and preventive strategies. Further, the robustness of our investigation is underscored by the substantial sample sizes employed in each MR analysis, coupled with the reliable estimation of the effect exerted by each IV, as evidenced by the F-statistics surpassing the threshold of 10. Ultimately, after employing MR-PRESSO to rule out pleiotropy, we further ensured the consistency of our causal estimates by conducting sensitivity analyses using the MR-Egger approach, leave-one-out analysis, and the weighted median method. This demonstrates the robustness of our research outcomes.

However, some limitations of the study should be noted in interpreting our findings. Firstly, sleep traits may differ between age groups, and subgroup analyses of different age groups should be performed in the future. Second, this study population was limited to a European population, which may limit the extrapolation of our results. Third, the reliance on questionnaires for assessing sleep duration in the primary research might have resulted in biases related to measurement inaccuracies. Fourth, daytime napping, sleep duration, and depression may have associations among themselves. The current MR analysis has not been able to verify the association between daytime napping, sleep duration and depression. It is hoped that some subsequent observational studies will explore this further. Fifth, considering that disease states may impact sleep characteristics, there may be a bidirectional relationship. This study did not carry out a two-sample MR study, and future studies could go deep into the effects of CVDs on sleep duration, daytime naps and depression. Fifth, considering that disease states may impact sleep characteristics, there may be a bidirectional relationship. This study did not carry out a two-sample MR study, and future studies could go deep into the effects of CVDs on sleep duration, daytime napping and depression. Finally, despite employing a range of methods to analyze pleiotropic effects, the possibility of directed pleiotropy’s influence cannot be entirely discounted. Fortunately, the use of multiple methods has yielded consistent findings, with no indications of heterogeneity or horizontal pleiotropy detected. Future studies need to be conducted to confirm causality and investigate underlying mechanisms.


Conclusions

This two-sample MR analysis revealed a causal positive association between daytime napping and the risk of several CVDs, including HF, coronary atherosclerosis, MI, and CAD. Conversely, a genetic predisposition to a longer sleep duration was linked to reduced risks of HF, PVD, and CAD. Additionally, depression was positively related to AF. These discoveries offer genetic proof to support the prevention of CVDs, with a particular focus on the significance of daytime naps, adequate sleep duration, and depression management.


Acknowledgments

We would like to thank all the reviewers for their assistance and support.

Funding: None.


Footnote

Reporting Checklist: The authors have completed the STROBE-MR reporting checklist. Available at https://cdt.amegroups.com/article/view/10.21037/cdt-24-313/rc

Peer Review File: Available at https://cdt.amegroups.com/article/view/10.21037/cdt-24-313/prf

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://cdt.amegroups.com/article/view/10.21037/cdt-24-313/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013).

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.


References

  1. Global Cardiovascular Risk Consortium. Global Effect of Modifiable Risk Factors on Cardiovascular Disease and Mortality. N Engl J Med 2023;389:1273-85. [Crossref] [PubMed]
  2. Ezzati M, Obermeyer Z, Tzoulaki I, et al. Contributions of risk factors and medical care to cardiovascular mortality trends. Nat Rev Cardiol 2015;12:508-30. [Crossref] [PubMed]
  3. Tsao CW, Aday AW, Almarzooq ZI, et al. Heart Disease and Stroke Statistics-2022 Update: A Report From the American Heart Association. Circulation 2022;145:e153-639. [Crossref] [PubMed]
  4. Chen D, Zhang Y, Yidilisi A, et al. Causal Associations Between Circulating Adipokines and Cardiovascular Disease: A Mendelian Randomization Study. J Clin Endocrinol Metab 2022;107:e2572-80. [Crossref] [PubMed]
  5. Ai S, Zhang J, Zhao G, et al. Causal associations of short and long sleep durations with 12 cardiovascular diseases: linear and nonlinear Mendelian randomization analyses in UK Biobank. Eur Heart J 2021;42:3349-57. [Crossref] [PubMed]
  6. Liu X, Li C, Sun X, et al. Genetically Predicted Insomnia in Relation to 14 Cardiovascular Conditions and 17 Cardiometabolic Risk Factors: A Mendelian Randomization Study. J Am Heart Assoc 2021;10:e020187. [Crossref] [PubMed]
  7. Li Y, Miao Y, Zhang Q. Causal associations of obstructive sleep apnea with cardiovascular disease: a Mendelian randomization study. Sleep 2023;46:zsac298. [Crossref] [PubMed]
  8. Ramos AR, Weng J, Wallace DM, et al. Sleep Patterns and Hypertension Using Actigraphy in the Hispanic Community Health Study/Study of Latinos. Chest 2018;153:87-93. [Crossref] [PubMed]
  9. Fu J, Zhang X, Moore JB, et al. Midday Nap Duration and Hypertension among Middle-Aged and Older Chinese Adults: A Nationwide Retrospective Cohort Study. Int J Environ Res Public Health 2021;18:3680. [Crossref] [PubMed]
  10. Fu Y, Feng S, Xu Y, et al. Association of Depression, Antidepressants With Atrial Fibrillation Risk: A Systemic Review and Meta-Analysis. Front Cardiovasc Med 2022;9:897622. [Crossref] [PubMed]
  11. Stergiou GS, Vemmos KN, Pliarchopoulou KM, et al. Parallel morning and evening surge in stroke onset, blood pressure, and physical activity. Stroke 2002;33:1480-6. [Crossref] [PubMed]
  12. Tanabe N, Iso H, Seki N, et al. Daytime napping and mortality, with a special reference to cardiovascular disease: the JACC study. Int J Epidemiol 2010;39:233-43. [Crossref] [PubMed]
  13. Burazeri G, Gofin J, Kark JD. Siesta and mortality in a Mediterranean population: a community study in Jerusalem. Sleep 2003;26:578-84. [Crossref] [PubMed]
  14. Xu Q, Song Y, Hollenbeck A, et al. Day napping and short night sleeping are associated with higher risk of diabetes in older adults. Diabetes Care 2010;33:78-83. [Crossref] [PubMed]
  15. Chen J, Chen J, Zhu T, et al. Causal relationships of excessive daytime napping with atherosclerosis and cardiovascular diseases: a Mendelian randomization study. Sleep 2023;46:zsac257. [Crossref] [PubMed]
  16. Zhao H, Gui W, Huang H, et al. Association of long-term sleep habits and hypertension: a cross-sectional study in Chinese adults. J Hum Hypertens 2020;34:378-87. [Crossref] [PubMed]
  17. Huang M, Yang Y, Huang Z, et al. The association of nighttime sleep duration and daytime napping duration with hypertension in Chinese rural areas: a population-based study. J Hum Hypertens 2021;35:896-902. [Crossref] [PubMed]
  18. Lian X, Gu J, Wang S, et al. Effects of sleep habits on acute myocardial infarction risk and severity of coronary artery disease in Chinese population. BMC Cardiovasc Disord 2021;21:481. [Crossref] [PubMed]
  19. Jia Y, Guo D, Sun L, et al. Self-reported daytime napping, daytime sleepiness, and other sleep phenotypes in the development of cardiometabolic diseases: a Mendelian randomization study. Eur J Prev Cardiol 2022;29:1982-91. [Crossref] [PubMed]
  20. Xiong Y, Yu Y, Cheng J, et al. Association of Sleep Duration, Midday Napping with Atrial Fibrillation in Patients with Hypertension. Clin Epidemiol 2022;14:385-93. [Crossref] [PubMed]
  21. Arafa A, Kokubo Y, Shimamoto K, et al. Sleep duration and atrial fibrillation risk in the context of predictive, preventive, and personalized medicine: the Suita Study and meta-analysis of prospective cohort studies. EPMA J 2022;13:77-86. [Crossref] [PubMed]
  22. Genuardi MV, Ogilvie RP, Saand AR, et al. Association of Short Sleep Duration and Atrial Fibrillation. Chest 2019;156:544-52. [Crossref] [PubMed]
  23. Chen J, Li F, Wang Y, et al. Short sleep duration and atrial fibrillation risk: A comprehensive analysis of observational cohort studies and genetic study. Eur J Intern Med 2023;114:84-92. [Crossref] [PubMed]
  24. Zhang X, Li G, Shi C, et al. Associations of sleep duration, daytime napping, and snoring with depression in rural China: a cross-sectional study. BMC Public Health 2023;23:1530. [Crossref] [PubMed]
  25. Um YJ, Kim Y, Chang Y, et al. Association of changes in sleep duration and quality with incidence of depression: A cohort study. J Affect Disord 2023;328:64-71. [Crossref] [PubMed]
  26. Li GH, Cheung CL, Chung AK, et al. Evaluation of bi-directional causal association between depression and cardiovascular diseases: a Mendelian randomization study. Psychol Med 2022;52:1765-76. [Crossref] [PubMed]
  27. Li L, Zhang Q, Zhu L, et al. Daytime naps and depression risk: A meta-analysis of observational studies. Front Psychol 2022;13:1051128. [Crossref] [PubMed]
  28. Wang L, Ding C. Major depression disorder may causally associate with the increased atrial fibrillation risk: evidence from two-sample mendelian randomization analyses. BMC Med Genomics 2023;16:144. [Crossref] [PubMed]
  29. Garg PK, O'Neal WT, Diez-Roux AV, et al. Negative Affect and Risk of Atrial Fibrillation: MESA. J Am Heart Assoc 2019;8:e010603. [Crossref] [PubMed]
  30. Goren A, Liu X, Gupta S, et al. Quality of life, activity impairment, and healthcare resource utilization associated with atrial fibrillation in the US National Health and Wellness Survey. PLoS One 2013;8:e71264. [Crossref] [PubMed]
  31. Whang W, Kubzansky LD, Kawachi I, et al. Depression and risk of sudden cardiac death and coronary heart disease in women: results from the Nurses' Health Study. J Am Coll Cardiol 2009;53:950-8. [Crossref] [PubMed]
  32. Scherrer JF, Garfield LD, Chrusciel T, et al. Increased risk of myocardial infarction in depressed patients with type 2 diabetes. Diabetes Care 2011;34:1729-34. [Crossref] [PubMed]
  33. Jackson CA, Pathirana T, Gardiner PA. Depression, anxiety and risk of hypertension in mid-aged women: a prospective longitudinal study. J Hypertens 2016;34:1959-66. [Crossref] [PubMed]
  34. Jeon SW, Chang Y, Lim SW, et al. Bidirectional association between blood pressure and depressive symptoms in young and middle-age adults: A cohort study. Epidemiol Psychiatr Sci 2020;29:e142. [Crossref] [PubMed]
  35. Ruan J, Xu YM, Zhong BL. Depressive disorders in older Chinese adults with essential hypertension: A classification tree analysis. Front Cardiovasc Med 2022;9:1035203. [Crossref] [PubMed]
  36. Qi H, Wen FY, Xie YY, et al. Associations between depressive, anxiety, stress symptoms and elevated blood pressure: Findings from the CHCN-BTH cohort study and a two-sample Mendelian randomization analysis. J Affect Disord 2023;341:176-84. [Crossref] [PubMed]
  37. Bowden J, Holmes MV. Meta-analysis and Mendelian randomization: A review. Res Synth Methods 2019;10:486-96. [Crossref] [PubMed]
  38. Smith GD, Ebrahim S. 'Mendelian randomization': can genetic epidemiology contribute to understanding environmental determinants of disease? Int J Epidemiol 2003;32:1-22. [Crossref] [PubMed]
  39. Gao N, Kong M, Li X, et al. Systemic Lupus Erythematosus and Cardiovascular Disease: A Mendelian Randomization Study. Front Immunol 2022;13:908831. [Crossref] [PubMed]
  40. Zheng J, Baird D, Borges MC, et al. Recent Developments in Mendelian Randomization Studies. Curr Epidemiol Rep 2017;4:330-45. [Crossref] [PubMed]
  41. Davies NM, Holmes MV, Davey Smith G. Reading Mendelian randomisation studies: a guide, glossary, and checklist for clinicians. BMJ 2018;362:k601. [Crossref] [PubMed]
  42. Andrews I, Stock JH, Sun LY. Weak Instruments in Instrumental Variables Regression: Theory and Practice. Ann Rev Econ 2019;11:727-53. [Crossref]
  43. Burgess S, Thompson SGCRP CHD Genetics Collaboration. Avoiding bias from weak instruments in Mendelian randomization studies. Int J Epidemiol 2011;40:755-64. [Crossref] [PubMed]
  44. Sudlow C, Gallacher J, Allen N, et al. UK biobank: an open access resource for identifying the causes of a wide range of complex diseases of middle and old age. PLoS Med 2015;12:e1001779. [Crossref] [PubMed]
  45. Dashti HS, Daghlas I, Lane JM, et al. Genetic determinants of daytime napping and effects on cardiometabolic health. Nat Commun 2021;12:900. [Crossref] [PubMed]
  46. Jones SE, Tyrrell J, Wood AR, et al. Genome-Wide Association Analyses in 128,266 Individuals Identifies New Morningness and Sleep Duration Loci. PLoS Genet 2016;12:e1006125. [Crossref] [PubMed]
  47. Shah S, Henry A, Roselli C, et al. Genome-wide association and Mendelian randomisation analysis provide insights into the pathogenesis of heart failure. Nat Commun 2020;11:163. [Crossref] [PubMed]
  48. van der Harst P, Verweij N. Identification of 64 Novel Genetic Loci Provides an Expanded View on the Genetic Architecture of Coronary Artery Disease. Circ Res 2018;122:433-43. [Crossref] [PubMed]
  49. Wojcik GL, Graff M, Nishimura KK, et al. Genetic analyses of diverse populations improves discovery for complex traits. Nature 2019;570:514-8. [Crossref] [PubMed]
  50. KurkiMIKarjalainenJPaltaP, editors. FinnGen: Unique genetic insights from combining isolated population and national health register data.medRxiv; 2022. DOI:.10.1101/2022.03.03.22271360
  51. Sakaue S, Kanai M, Tanigawa Y, et al. A cross-population atlas of genetic associations for 220 human phenotypes. Nat Genet 2021;53:1415-24. [Crossref] [PubMed]
  52. Malik R, Chauhan G, Traylor M, et al. Multiancestry genome-wide association study of 520,000 subjects identifies 32 loci associated with stroke and stroke subtypes. Nat Genet 2018;50:524-37. [Crossref] [PubMed]
  53. Nielsen JB, Thorolfsdottir RB, Fritsche LG, et al. Biobank-driven genomic discovery yields new insight into atrial fibrillation biology. Nat Genet 2018;50:1234-9. [Crossref] [PubMed]
  54. Dönertaş HM, Fabian DK, Valenzuela MF, et al. Common genetic associations between age-related diseases. Nat Aging 2021;1:400-12. [Crossref] [PubMed]
  55. Locke AE, Kahali B, Berndt SI, et al. Genetic studies of body mass index yield new insights for obesity biology. Nature 2015;518:197-206. [Crossref] [PubMed]
  56. Liu M, Jiang Y, Wedow R, et al. Association studies of up to 1.2 million individuals yield new insights into the genetic etiology of tobacco and alcohol use. Nat Genet 2019;51:237-44. [Crossref] [PubMed]
  57. Chen S, Hu Z, He L, et al. Relationship between daytime napping and cardiovascular disease: A two-sample mendelian randomization study. Hellenic J Cardiol 2024;75:26-31. [Crossref] [PubMed]
  58. Mongia SK, Little RR, Rohlfing CL, et al. Effects of hemoglobin C and S traits on the results of 14 commercial glycated hemoglobin assays. Am J Clin Pathol 2008;130:136-40. [Crossref] [PubMed]
  59. Brion MJ, Shakhbazov K, Visscher PM. Calculating statistical power in Mendelian randomization studies. Int J Epidemiol 2013;42:1497-501. [Crossref] [PubMed]
  60. Wannamethee SG, Papacosta O, Lennon L, et al. Self-Reported Sleep Duration, Napping, and Incident Heart Failure: Prospective Associations in the British Regional Heart Study. J Am Geriatr Soc 2016;64:1845-50. [Crossref] [PubMed]
  61. Li P, Gaba A, Wong PM, et al. Objective Assessment of Daytime Napping and Incident Heart Failure in 1140 Community-Dwelling Older Adults: A Prospective, Observational Cohort Study. J Am Heart Assoc 2021;10:e019037. [Crossref] [PubMed]
  62. Yamada T, Hara K, Shojima N, et al. Daytime Napping and the Risk of Cardiovascular Disease and All-Cause Mortality: A Prospective Study and Dose-Response Meta-Analysis. Sleep 2015;38:1945-53. [Crossref] [PubMed]
  63. Naska A, Oikonomou E, Trichopoulou A, et al. Siesta in healthy adults and coronary mortality in the general population. Arch Intern Med 2007;167:296-301. [Crossref] [PubMed]
  64. Harada CN, Natelson Love MC, Triebel KL. Normal cognitive aging. Clin Geriatr Med 2013;29:737-52. [Crossref] [PubMed]
  65. Murman DL. The Impact of Age on Cognition. Semin Hear 2015;36:111-21. [Crossref] [PubMed]
  66. Lennon LT, Ramsay SE, Papacosta O, et al. Cohort Profile Update: The British Regional Heart Study 1978-2014: 35 years follow-up of cardiovascular disease and ageing. Int J Epidemiol 2015;44:826-826g. [Crossref] [PubMed]
  67. McMurray JJ, Adamopoulos S, Anker SD, et al. ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure 2012: The Task Force for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2012 of the European Society of Cardiology. Developed in collaboration with the Heart Failure Association (HFA) of the ESC. Eur Heart J 2012;33:1787-847. [Crossref] [PubMed]
  68. Cowie MR, Linz D, Redline S, et al. Sleep Disordered Breathing and Cardiovascular Disease: JACC State-of-the-Art Review. J Am Coll Cardiol 2021;78:608-24. [Crossref] [PubMed]
  69. Stang A, Dragano N, Moebus S, et al. Midday naps and the risk of coronary artery disease: results of the Heinz Nixdorf Recall Study. Sleep 2012;35:1705-12. [Crossref] [PubMed]
  70. Booth JN 3rd, Jaeger BC, Huang L, et al. Morning Blood Pressure Surge and Cardiovascular Disease Events and All-Cause Mortality in Blacks: The Jackson Heart Study. Hypertension 2020;75:835-43. [Crossref] [PubMed]
  71. Gottlieb DJ, Yenokyan G, Newman AB, et al. Prospective study of obstructive sleep apnea and incident coronary heart disease and heart failure: the sleep heart health study. Circulation 2010;122:352-60. [Crossref] [PubMed]
  72. Cené CW, Loehr L, Lin FC, et al. Social isolation, vital exhaustion, and incident heart failure: findings from the Atherosclerosis Risk in Communities Study. Eur J Heart Fail 2012;14:748-53. [Crossref] [PubMed]
  73. Leng Y, Wainwright NW, Cappuccio FP, et al. Daytime napping and the risk of all-cause and cause-specific mortality: a 13-year follow-up of a British population. Am J Epidemiol 2014;179:1115-24. [Crossref] [PubMed]
  74. Leng Y, Ahmadi-Abhari S, Wainwright NW, et al. Daytime napping, sleep duration and serum C reactive protein: a population-based cohort study. BMJ Open 2014;4:e006071. [Crossref] [PubMed]
  75. Thygesen K, Alpert JS, Jaffe AS, et al. Fourth Universal Definition of Myocardial Infarction (2018). J Am Coll Cardiol 2018;72:2231-64. [Crossref] [PubMed]
  76. King M, Kingery J, Casey B. Diagnosis and evaluation of heart failure. Am Fam Physician 2012;85:1161-8. [PubMed]
  77. Guo M, Feng T, Liu M, et al. Causal roles of daytime sleepiness in cardiometabolic diseases and osteoporosis. Eur Rev Med Pharmacol Sci 2022;26:2755-64. [PubMed]
  78. Tasali E, Leproult R, Ehrmann DA, et al. Slow-wave sleep and the risk of type 2 diabetes in humans. Proc Natl Acad Sci U S A 2008;105:1044-9. [Crossref] [PubMed]
  79. Endo S, Kobayashi T, Yamamoto T, et al. Persistence of the circadian rhythm of REM sleep: a variety of experimental manipulations of the sleep-wake cycle. Sleep 1981;4:319-28. [Crossref] [PubMed]
  80. Yang Y, Fan J, Shi X, et al. Causal associations between sleep traits and four cardiac diseases: a Mendelian randomization study. ESC Heart Fail 2022;9:3160-6. [Crossref] [PubMed]
  81. Aggarwal S, Loomba RS, Arora RR, et al. Associations between sleep duration and prevalence of cardiovascular events. Clin Cardiol 2013;36:671-6. [Crossref] [PubMed]
  82. Wang S, Li Z, Wang X, et al. Associations between sleep duration and cardiovascular diseases: A meta-review and meta-analysis of observational and Mendelian randomization studies. Front Cardiovasc Med 2022;9:930000. [Crossref] [PubMed]
  83. Lao XQ, Liu X, Deng HB, et al. Sleep Quality, Sleep Duration, and the Risk of Coronary Heart Disease: A Prospective Cohort Study With 60,586 Adults. J Clin Sleep Med 2018;14:109-17. [Crossref] [PubMed]
  84. van Oort S, Beulens JWJ, van Ballegooijen AJ, et al. Modifiable lifestyle factors and heart failure: A Mendelian randomization study. Am Heart J 2020;227:64-73. [Crossref] [PubMed]
  85. Zhuang S, Huang S, Huang Z, et al. Prospective study of sleep duration, snoring and risk of heart failure. Heart 2023;heartjnl-2022-321799.
  86. Hayes D Jr, Anstead MI, Ho J, et al. Insomnia and chronic heart failure. Heart Fail Rev 2009;14:171-82. [Crossref] [PubMed]
  87. Riegel B, Moser DK, Anker SD, et al. State of the science: promoting self-care in persons with heart failure: a scientific statement from the American Heart Association. Circulation 2009;120:1141-63. [Crossref] [PubMed]
  88. van Bilsen M, Patel HC, Bauersachs J, et al. The autonomic nervous system as a therapeutic target in heart failure: a scientific position statement from the Translational Research Committee of the Heart Failure Association of the European Society of Cardiology. Eur J Heart Fail 2017;19:1361-78. [Crossref] [PubMed]
  89. Türoff A, Thiem U, Fox H, et al. Sleep duration and quality in heart failure patients. Sleep Breath 2017;21:919-27. [Crossref] [PubMed]
  90. Zhuang Z, Gao M, Yang R, et al. Association of physical activity, sedentary behaviours and sleep duration with cardiovascular diseases and lipid profiles: a Mendelian randomization analysis. Lipids Health Dis 2020;19:86. [Crossref] [PubMed]
  91. Yuan S, Levin MG, Titova OE, et al. Sleep duration, daytime napping, and risk of peripheral artery disease: multinational cohort and Mendelian randomization studies. Eur Heart J Open 2023;3:oead008. [Crossref] [PubMed]
  92. Ferrie JE, Kivimäki M, Akbaraly TN, et al. Associations between change in sleep duration and inflammation: findings on C-reactive protein and interleukin 6 in the Whitehall II Study. Am J Epidemiol 2013;178:956-61. [Crossref] [PubMed]
  93. Meier-Ewert HK, Ridker PM, Rifai N, et al. Effect of sleep loss on C-reactive protein, an inflammatory marker of cardiovascular risk. J Am Coll Cardiol 2004;43:678-83. [Crossref] [PubMed]
  94. Tobaldini E, Fiorelli EM, Solbiati M, et al. Short sleep duration and cardiometabolic risk: from pathophysiology to clinical evidence. Nat Rev Cardiol 2019;16:213-24. [Crossref] [PubMed]
  95. Spiegel K, Tasali E, Penev P, et al. Brief communication: Sleep curtailment in healthy young men is associated with decreased leptin levels, elevated ghrelin levels, and increased hunger and appetite. Ann Intern Med 2004;141:846-50. [Crossref] [PubMed]
  96. Taheri S, Lin L, Austin D, et al. Short sleep duration is associated with reduced leptin, elevated ghrelin, and increased body mass index. PLoS Med 2004;1:e62. [Crossref] [PubMed]
  97. Spiegel K, Tasali E, Leproult R, et al. Effects of poor and short sleep on glucose metabolism and obesity risk. Nat Rev Endocrinol 2009;5:253-61. [Crossref] [PubMed]
  98. Knutson KL, Spiegel K, Penev P, et al. The metabolic consequences of sleep deprivation. Sleep Med Rev 2007;11:163-78. [Crossref] [PubMed]
  99. Landsberg L, Aronne LJ, Beilin LJ, et al. Obesity-related hypertension: pathogenesis, cardiovascular risk, and treatment: a position paper of The Obesity Society and the American Society of Hypertension. J Clin Hypertens (Greenwich) 2013;15:14-33. [Crossref] [PubMed]
  100. Spiegel K, Knutson K, Leproult R, et al. Sleep loss: a novel risk factor for insulin resistance and Type 2 diabetes. J Appl Physiol (1985) 2005;99:2008-19. [PubMed]
  101. Barton M, Baretella O, Meyer MR. Obesity and risk of vascular disease: importance of endothelium-dependent vasoconstriction. Br J Pharmacol 2012;165:591-602. [Crossref] [PubMed]
  102. St-Onge MP, Grandner MA, Brown D, et al. Sleep Duration and Quality: Impact on Lifestyle Behaviors and Cardiometabolic Health: A Scientific Statement From the American Heart Association. Circulation 2016;134:e367-86. [Crossref] [PubMed]
  103. Tellez-Plaza M, Guallar E, Fabsitz RR, et al. Cadmium exposure and incident peripheral arterial disease. Circ Cardiovasc Qual Outcomes 2013;6:626-33. [Crossref] [PubMed]
  104. Taylor BV, Oudit GY, Kalman PG, et al. Clinical and pathophysiological effects of active and passive smoking on the cardiovascular system. Can J Cardiol 1998;14:1129-39. [PubMed]
  105. Willigendael EM, Teijink JA, Bartelink ML, et al. Influence of smoking on incidence and prevalence of peripheral arterial disease. J Vasc Surg 2004;40:1158-65. [Crossref] [PubMed]
  106. Norgren L, Hiatt WR, Dormandy JA, et al. Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC II). J Vasc Surg 2007;45 Suppl S:S5-67.
  107. Ambrose JA, Barua RS. The pathophysiology of cigarette smoking and cardiovascular disease: an update. J Am Coll Cardiol 2004;43:1731-7. [Crossref] [PubMed]
  108. Salahuddin S, Prabhakaran D, Roy A. Pathophysiological Mechanisms of Tobacco-Related CVD. Glob Heart 2012;7:113-20. [Crossref] [PubMed]
  109. Daghlas I, Dashti HS, Lane J, et al. Sleep Duration and Myocardial Infarction. J Am Coll Cardiol 2019;74:1304-14. [Crossref] [PubMed]
  110. Wang C, Hao G, Bo J, et al. Correlations between sleep patterns and cardiovascular diseases in a Chinese middle-aged population. Chronobiol Int 2017;34:601-8. [Crossref] [PubMed]
  111. Yang X, Chen H, Li S, et al. Association of Sleep Duration with the Morbidity and Mortality of Coronary Artery Disease: A Meta-analysis of Prospective Studies. Heart Lung Circ 2015;24:1180-90. [Crossref] [PubMed]
  112. Cappuccio FP, Cooper D, D'Elia L, et al. Sleep duration predicts cardiovascular outcomes: a systematic review and meta-analysis of prospective studies. Eur Heart J 2011;32:1484-92. [Crossref] [PubMed]
  113. Wang D, Li W, Cui X, et al. Sleep duration and risk of coronary heart disease: A systematic review and meta-analysis of prospective cohort studies. Int J Cardiol 2016;219:231-9. [Crossref] [PubMed]
  114. Mullington JM, Haack M, Toth M, et al. Cardiovascular, inflammatory, and metabolic consequences of sleep deprivation. Prog Cardiovasc Dis 2009;51:294-302. [Crossref] [PubMed]
  115. Maurovich-Horvat E, Pollmächer TZ, Sonka K. The effects of sleep and sleep deprivation on metabolic, endocrine and immune parameters. Prague Med Rep 2008;109:275-85. [PubMed]
  116. Dominguez-Rodriguez A, Abreu-Gonzalez P. The link between sleep duration and inflammation: effects on cardiovascular disease. Int J Cardiol 2014;173:600-1. [Crossref] [PubMed]
  117. Cherubini JM, Cheng JL, Williams JS, et al. Sleep deprivation and endothelial function: reconciling seminal evidence with recent perspectives. Am J Physiol Heart Circ Physiol 2021;320:H29-35. [Crossref] [PubMed]
  118. King CR, Knutson KL, Rathouz PJ, et al. Short sleep duration and incident coronary artery calcification. JAMA 2008;300:2859-66. [Crossref] [PubMed]
  119. Wolff B, Völzke H, Schwahn C, et al. Relation of self-reported sleep duration with carotid intima-media thickness in a general population sample. Atherosclerosis 2008;196:727-32. [Crossref] [PubMed]
  120. Stock AA, Lee S, Nahmod NG, et al. Effects of sleep extension on sleep duration, sleepiness, and blood pressure in college students. Sleep Health 2020;6:32-9. [Crossref] [PubMed]
  121. Haack M, Serrador J, Cohen D, et al. Increasing sleep duration to lower beat-to-beat blood pressure: a pilot study. J Sleep Res 2013;22:295-304. [Crossref] [PubMed]
  122. Larsson SC, Burgess S, Michaëlsson K. Smoking and stroke: A mendelian randomization study. Ann Neurol 2019;86:468-71. [Crossref] [PubMed]
  123. Harshfield EL, Georgakis MK, Malik R, et al. Modifiable Lifestyle Factors and Risk of Stroke: A Mendelian Randomization Analysis. Stroke 2021;52:931-6. [Crossref] [PubMed]
  124. Hackshaw A, Morris JK, Boniface S, et al. Low cigarette consumption and risk of coronary heart disease and stroke: meta-analysis of 141 cohort studies in 55 study reports. BMJ 2018;360:j5855. [Crossref] [PubMed]
  125. Rigotti NA, Clair C. Managing tobacco use: the neglected cardiovascular disease risk factor. Eur Heart J 2013;34:3259-67. [Crossref] [PubMed]
  126. Seo EJ, Son YJ. The Prevalence of Cognitive Frailty and Its Association with Sleep duration and Depression Among Older Adults with Heart Failure. Clin Gerontol 2024;47:416-25. [Crossref] [PubMed]
  127. Seo EJ, Won MH, Son YJ. Association of sleep duration and physical frailty with cognitive function in older patients with coexisting atrial fibrillation and heart failure. Nurs Open 2023;10:3201-9. [Crossref] [PubMed]
  128. Kim JH, Hayek SS, Ko YA, et al. Sleep Duration and Mortality in Patients With Coronary Artery Disease. Am J Cardiol 2019;123:874-81. [Crossref] [PubMed]
  129. Ayas NT, White DP, Manson JE, et al. A prospective study of sleep duration and coronary heart disease in women. Arch Intern Med 2003;163:205-9. [Crossref] [PubMed]
  130. da Silva AA, de Mello RG, Schaan CW, et al. Sleep duration and mortality in the elderly: a systematic review with meta-analysis. BMJ Open 2016;6:e008119. [Crossref] [PubMed]
  131. Hale L, Parente V, Dowd JB, et al. Fibrinogen may mediate the association between long sleep duration and coronary heart disease. J Sleep Res 2013;22:305-14. [Crossref] [PubMed]
  132. Zhang F, Baranova A, Zhou C, et al. Causal influences of neuroticism on mental health and cardiovascular disease. Hum Genet 2021;140:1267-81. [Crossref] [PubMed]
  133. Zhang F, Cao H, Baranova A. Shared Genetic Liability and Causal Associations Between Major Depressive Disorder and Cardiovascular Diseases. Front Cardiovasc Med 2021;8:735136. [Crossref] [PubMed]
  134. Baranova A, Cao H, Zhang F. Shared genetic liability and causal effects between major depressive disorder and insomnia. Hum Mol Genet 2022;31:1336-45. [Crossref] [PubMed]
  135. Zhang F, Cao H, Baranova A. Genetic variation mediating neuroticism's influence on cardiovascular diseases. J Psychopathol Clin Sci 2022;131:278-86. [Crossref] [PubMed]
  136. Zhou H, Ji Y, Sun L, et al. Exploring the causal relationships and mediating factors between depression, anxiety, panic, and atrial fibrillation: A multivariable Mendelian randomization study. J Affect Disord 2024;349:635-45. [Crossref] [PubMed]
  137. Manolis TA, Manolis AA, Apostolopoulos EJ, et al. Depression and atrial fibrillation in a reciprocal liaison: a neuro-cardiac link. Int J Psychiatry Clin Pract 2023;27:397-415. [Crossref] [PubMed]
  138. Kim YG, Lee KN, Han KD, et al. Association of Depression With Atrial Fibrillation in South Korean Adults. JAMA Netw Open 2022;5:e2141772. [Crossref] [PubMed]
  139. Pasic J, Levy WC, Sullivan MD. Cytokines in depression and heart failure. Psychosom Med 2003;65:181-93. [Crossref] [PubMed]
  140. Patel D, Mc Conkey ND, Sohaney R, et al. A systematic review of depression and anxiety in patients with atrial fibrillation: the mind-heart link. Cardiovasc Psychiatry Neurol 2013;2013:159850. [Crossref] [PubMed]
  141. Chithiramohan T, Parekh JN, Kronenberg G, et al. Investigating the association between depression and cerebral haemodynamics-A systematic review and meta-analysis. J Affect Disord 2022;299:144-58. [Crossref] [PubMed]
  142. Ding N, Shah AM, Blaha MJ, et al. Cigarette Smoking, Cessation, and Risk of Heart Failure With Preserved and Reduced Ejection Fraction. J Am Coll Cardiol 2022;79:2298-305. [Crossref] [PubMed]
  143. Kamimura D, Cain LR, Mentz RJ, et al. Cigarette Smoking and Incident Heart Failure: Insights From the Jackson Heart Study. Circulation 2018;137:2572-82. [Crossref] [PubMed]
  144. Pujades-Rodriguez M, George J, Shah AD, et al. Heterogeneous associations between smoking and a wide range of initial presentations of cardiovascular disease in 1937360 people in England: lifetime risks and implications for risk prediction. Int J Epidemiol 2015;44:129-41. [Crossref] [PubMed]
  145. Wilhelmsen L, Rosengren A, Eriksson H, et al. Heart failure in the general population of men--morbidity, risk factors and prognosis. J Intern Med 2001;249:253-61. [PubMed]
Cite this article as: Li Y, Garg PK, Wu J. Associations between daytime napping, sleep duration, and depression and 15 cardiovascular diseases: a Mendelian randomization study. Cardiovasc Diagn Ther 2024;14(5):771-787. doi: 10.21037/cdt-24-313

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