Quality of life in adults with congenital heart disease with and without pulmonary hypertension: a comparative study
Introduction
Pulmonary vascular disease and pulmonary hypertension (PH) are among the most relevant complications associated with congenital heart defects (CHD) and responsible for a high morbidity and mortality (1,2). Although epidemiological data are scarce, the estimated prevalence of pre- or postcapillary forms of PH in adults with CHD (ACHD) is ranging from 3.2% to 28% (3-5). The clinical classification of PH in CHD (PH-CHD) comprises the Eisenmenger Syndrome (ES), PH associated with a predominant systemic-to-pulmonary shunt, PH associated with a small defect, and PH associated with a repaired defect, as well as special forms such as pulmonary vascular disease in Fontan circulation (6). Only recent advances in research and treatment of PH have led to increasing survival rates (7). Although it is well known that patients with idiopathic forms of PH are at risk for a severely impaired quality of life (QOL) (8), reports on impaired QOL due to PH-CHD are still limited and not routinely employed in general care of this particular patient population. Additionally, previous studies have shown that QOL can be an important determinant of health outcomes in patients with PH (9). Although the relationship between QOL and clinical outcomes is not fully elucidated, QOL has been identified as a prognostic marker in the prognosis, survival rate and treatment response of PH patients (9). Consequently, the management goals of PH-CHD should be expanded from prolonging mere survival to improving QOL.
In light of this, the aim of this study was to (I) systematically assess QOL in PH-CHD patients and (II) compare findings to patients with other forms of CHD with normal pulmonary artery pressures and resistance. Obtained findings should generate a differentiated understanding of the psychological situation in PH-CHD patients and may open up productive avenues for psychosocial, health promoting interventions to further enhance both, QOL and longevity in this particular patient population. We present the following article in accordance with the STROBE reporting checklist (available at https://cdt.amegroups.com/article/view/10.21037/cdt-22-284/rc).
Methods
Study population
The present comparative study was part of a recent nationwide survey about the healthcare situation of ACHD throughout Germany (“VEmaH study”), in which more than 4,000 patients were enrolled (10). Within this survey, a consecutively recruited subgroup of 803 ACHD was analyzed (Figure S1). Data collection took place from September 2017 until February 2018. For inclusion, patients had to fulfill the following criteria: (I) confirmed diagnosis of CHD, (II) participation in the preceding VemaH study, (III) age over 18 years, and (IV) enrollment as a patient at the German Heart Center Munich. Patients were categorized into two subgroups: (A) CHD without PH, and (B) CHD with manifest PH. Allocation to collective (B) was done according to the established PH criteria valid at that time (6,11). The categorization was conducted by experienced CHD cardiologists based on the clinical experience and according to data from the literature.
Measures
Medical records were reviewed for healthcare related information, sociodemographic parameters, relevant medical history, type of leading CHD, existing residua/sequelae, and surgical/interventional status.
For the assessment of QOL, the European Quality of Life 5-dimensional questionnaire (EQ-5D-5L) was used. The EQ-5D-5L provides a tool for the measurement of a patient’s perceived health status. It has been validated for self-administration with high psychometric properties (12). The questionnaire consists of two sections: a descriptive system questionnaire (EQ-Index) and a visual analogue scale (EQ-VAS). The EQ-Index refers to five dimensions: three for functional aspects (mobility, self-care, routine activities), and the other two for physical and mental well-being (pain/discomfort and anxiety/depression). Patients are asked to indicate the level of their perceived impairments on a 5-point Likert scale (ranging from moderate to severe problems). Responses are represented as single-digit numbers expressing the severity of impairment on each dimension. A single weighted index score (EQ-5D index) can be calculated using population reference scores. The EQ-VAS indicates a patient’s overall health state on a continuous scale ranging from 0 (“The worst health you can imagine”) to 100 (“The best health you can imagine”). It is used as a quantitative indicator of a patient’s perceived generic health status.
The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013) and approved by the local ethics committee of the Technical University Munich (157/16 S). All participants completed an informed consent form. Guidelines on good pharmacoepidemiological practice (GPP) and all relevant data protection guidelines were followed.
Statistical analysis
Data analysis was performed using IBM SPSS 25.0 (IBM Inc., Armonk, NY, USA). All statistical evaluations were pseudonymized. Descriptive measures were calculated for sociodemographic sample characteristics. Group differences were assessed using t-tests, and chi-square. Continuous data was expressed as mean ± standard deviation (SD), categorical or interval scaled variables as absolute numbers or percentages. The crosswalk-index-value of the EQ5D-5L was calculated using the German value set (13). The 95% confidence interval (CI) is displayed as lower- and upper-bound. P values and tests for significance were performed two-sided, on an α-level of 0.05.
Results
A total of 803 patients (female: n=384, 47.8%) was included in the study. The mean age was 35.4±11.9 years (range, 18–86 years).
According to the allocation criteria for the different risk groups, 752 patients [47.3% female; mean age 34.9±11.83 years (range, 18–86 years)] had no PH due to their CHD. In total, 51 patients were diagnosed with manifest PH [55.8% female; mean age: 41.9±12.17 years (range, 21–69 years)]. The two subsets differed significantly in age (P<0.001) but not in sex (P=0.254). Table 1 shows relevant medical parameters, comorbidities, and surgical/interventional status of the included ACHD by subgroups.
Table 1
Anamnestic parameters | Overall | No PH | Manifest PH | |||||
---|---|---|---|---|---|---|---|---|
N | % | n | % | n | % | |||
Functional class according to Perloff | ||||||||
I/II | 759 | 94.8 | 726 | 96.7 | 33 | 66.0 | ||
III | 40 | 5.0 | 25 | 33.3 | 15 | 30.0 | ||
IV | 2 | 0.2 | 0 | 0 | 2 | 4.0 | ||
Cyanosis (O2<90%) | ||||||||
No | 759 | 94.9 | 728 | 97.1 | 31 | 62.0 | ||
Yes | 30 | 3.8 | 12 | 1.6 | 18 | 36.0 | ||
Unknown | 11 | 1.4 | 10 | 1.3 | 1 | 2.0 | ||
ES | ||||||||
No | 778 | 97.3 | 746 | 99.5 | 32 | 64.0 | ||
Yes | 22 | 2.8 | 4 | 0.5 | 18 | 36.0 | ||
Ventricular function (Echo) | ||||||||
Normal | 705 | 88.5 | 668 | 89.3 | 37 | 75.5 | ||
Moderate reduced | 70 | 8.8 | 59 | 7.9 | 11 | 22.4 | ||
Severe reduced | 9 | 1.1 | 8 | 1.1 | 1 | 2.0 | ||
Unknown | 13 | 1.6 | 13 | 1.7 | 0 | 0 | ||
Infective endocarditis | ||||||||
No | 761 | 95.1 | 716 | 95.5 | 45 | 90.0 | ||
Yes | 24 | 3.0 | 20 | 2.7 | 4 | 8.0 | ||
Unknown | 15 | 1.9 | 14 | 1.9 | 1 | 2.0 | ||
Cardiac decompensation | ||||||||
No | 724 | 90.6 | 692 | 92.4 | 32 | 64.0 | ||
Yes | 55 | 6.9 | 42 | 5.6 | 13 | 26.0 | ||
Unknown | 20 | 2.5 | 15 | 2.0 | 5 | 10.0 | ||
Atrial arrhythmias | ||||||||
No | 624 | 78.0 | 595 | 79.3 | 29 | 58.0 | ||
Yes | 169 | 21.1 | 149 | 19.9 | 20 | 40.0 | ||
Unknown | 7 | 0.9 | 6 | 0.8 | 1 | 2.0 | ||
Arrhythmias | ||||||||
No | 603 | 75.3 | 572 | 76.2 | 31 | 62.0 | ||
Yes | 198 | 24.7 | 179 | 23.8 | 19 | 38.0 | ||
Ventricular arrhythmias | ||||||||
No | 714 | 89.8 | 665 | 90.5 | 39 | 78.0 | ||
Yes | 72 | 9.1 | 61 | 8.3 | 11 | 22.0 | ||
Unknown | 9 | 1.1 | 9 | 1.2 | 0 | 0 | ||
Arterial hypertension | ||||||||
No hypertension (<140/<90 mmHg) | 540 | 67.6 | 510 | 68.1 | 30 | 60.0 | ||
Currently under therapy | 163 | 20.4 | 145 | 19.4 | 18 | 36.0 | ||
Mild hypertension (140–159/90–99 mmHg) | 56 | 7.0 | 55 | 7.3 | 1 | 2.0 | ||
Moderate hypertension (160–179/100–109 mmHg) | 16 | 2.0 | 15 | 2.0 | 1 | 2.0 | ||
Unknown | 24 | 3.0 | 24 | 3.2 | 0 | 0 | ||
Aortopathy | ||||||||
No | 676 | 84.4 | 631 | 84.0 | 45 | 90.0 | ||
Yes | 125 | 15.6 | 120 | 16.0 | 5 | 10.0 | ||
Thromboembolic events | ||||||||
No | 652 | 81.5 | 617 | 82.4 | 35 | 70.0 | ||
Unknown | 52 | 6.5 | 47 | 6.3 | 5 | 10.0 | ||
Phlebothrombosis | 12 | 1.5 | 10 | 1.3 | 1 | 2.0 | ||
Pulmonary embolism | 3 | 0.4 | 1 | 0.1 | 2 | 4.0 | ||
TIA, RIND or stroke | 65 | 8.1 | 59 | 7.9 | 6 | 12.0 | ||
Peripheral artery disease | 16 | 2.0 | 15 | 2.0 | 1 | 2.0 | ||
Hyperlipidemia | ||||||||
No | 332 | 41.6 | 307 | 41.0 | 25 | 50.0 | ||
Yes | 69 | 8.6 | 60 | 8.0 | 9 | 18.0 | ||
Unknown | 398 | 49.8 | 382 | 51.0 | 16 | 32.0 | ||
Hyperurikemia | ||||||||
No | 353 | 44.2 | 335 | 44.7 | 18 | 36.0 | ||
Yes | 48 | 6.0 | 33 | 4.4 | 15 | 30.0 | ||
Unknown | 398 | 49.8 | 381 | 50.9 | 17 | 34.0 | ||
Diabetes mellitus | ||||||||
No | 342 | 43.2 | 321 | 43.3 | 21 | 42.9 | ||
Type I | 0 | 0 | 0 | 0 | 0 | 0 | ||
Type II | 25 | 3.2 | 21 | 2.8 | 4 | 8.2 | ||
Unknown | 424 | 53.6 | 400 | 53.9 | 24 | 49.0 | ||
Other (extracardiac) comorbidities | ||||||||
No | 400 | 49.9 | 378 | 50.3 | 22 | 44.0 | ||
Yes | 401 | 50.1 | 373 | 49.7 | 28 | 56.0 |
CHD, congenital heart disease; PH, pulmonary hypertension; ES, Eisenmenger Syndrome; TIA, transient ischemic attack; RIND, reversible ischemic neurological deficit.
A comparison of the subscales of the EQ-5D-5L for the different risk groups can be found in Table 2. In general, most patients presented without symptoms in any of the five dimensions. The highest degree of impairment could be seen in the dimensions of pain/discomfort as well as in anxiety/depression and for PH-CHD patients in usual activities (Figure 1). For the dimension of mobility (P<0.001), self-care (P=0.002) and usual activities (P=0.007), significant differences between the groups were found. Only for pain/discomfort (P=0.235) and anxiety and depression no significant group differences were detected (P=0.166).
Table 2
EQ-5D-5L dimension | Overall, n (%) | No PH, n (%) | Manifest PH, n (%) | 95% CI | P value |
---|---|---|---|---|---|
Mobility | (−0.46, −0.04) | <0.001 | |||
No problems | 613 (83.1) | 580 (84.5) | 33 (63.5) | ||
Slight problems | 72 (9.8) | 59 (8.6) | 13 (25.0) | ||
Moderate problems | 38 (1.4) | 32 (4.7) | 6 (11.5) | ||
Severe problems | 10 (5.1) | 10 (1.5) | 0 | ||
Extreme problems | 5 (0.7) | 5 (0.7) | 0 | ||
Self-care | (−0.51, −0.04) | 0.002 | |||
No problems | 696 (94.6) | 652 (95.2) | 44 (86.3) | ||
Slight problems | 26 (3.5) | 19 (2.8) | 7 (13.7) | ||
Moderate problems | 6 (0.8) | 6 (0.9) | 0 | ||
Severe problems | 6 (0.8) | 6 (0.9) | 0 | ||
Extreme problems | 2 (0.3) | 2 (0.3) | 0 | ||
Usual activities | (−0.57, −0.06) | 0.007 | |||
No problems | 547 (74.7) | 518 (76.1) | 29 (56.9) | ||
Slight problems | 104 (14.2) | 93 (13.7) | 11 (21.6) | ||
Moderate problems | 58 (7.9) | 48 (7.0) | 10 (19.6) | ||
Severe problems | 19 (2.6) | 18 (2.6) | 1 (2.0) | ||
Extreme problems | 4 (0.5) | 4 (0.6) | 0 | ||
Pain/discomfort | (−0.42, 0.02) | 0.235 | |||
No problems | 484 (66.2) | 457 (67.3) | 27 (51.9) | ||
Slight problems | 165 (22.6) | 148 (21.8) | 17 (32.7) | ||
Moderate problems | 67 (9.2) | 60 (8.8) | 7 (13.5) | ||
Severe problems | 13 (1.8) | 12 (1.8) | 1 (1.9) | ||
Extreme problems | 2 (0.3) | 2 (0.3) | 0 | ||
Anxiety/depression | (−0.55, 0) | 0.166 | |||
No problems | 469 (64.2) | 442 (65.0) | 27 (52.9) | ||
Slight problems | 176 (24.1) | 163 (24.0) | 13 (25.5) | ||
Moderate problems | 56 (7.7) | 48 (7.1) | 8 (15.7) | ||
Severe problems | 28 (3.8) | 25 (3.7) | 3 (5.9) | ||
Extreme problems | 2 (0.3) | 2 (0.3) | 0 |
QOL, quality of life; PH, pulmonary hypertension; EQ-5D-5L, European Quality of Life 5 Dimensions—5 Levels questionnaire; CI, confidence interval.
Significant differences were found between the patient groups for all QOL measurement dimensions (P<0.05). PH-CHD patients demonstrated worse QOL than patients without PH. Comparison between the patient groups showed significant differences in terms of overall QOL [mean no PH: 86.78±13.30 (8.2–100) vs. mean PH: 81.79±12.77 (43.6–100); 95% confidence interval (CI): 1.43 to 9.46; P=0.013], the crosswalk index [mean no PH: 93.29±12.86 (−11, 100) vs. mean PH: 89.73±11.77 (47–100); 95% CI: 0.08 to 7.56; P=0.043], and the VAS [mean no PH: 80.12±16.50 (15–100) vs. mean PH: 72.56±16.80 (40–100); 95% CI: 3.29 to 12.17; P=0.004] (Table 3).
Table 3
Dimension | Overall (mean ± SD; range) | No PH (mean ± SD; range) | Manifest PH (mean ± SD; range) | 95% CI | P value |
---|---|---|---|---|---|
Crosswalk* | 93.03±12.84; [−11, 100] | 93.29±12.86; [−11, 100] | 89.73±11.77; [47, 100] | 0.08 to 7.56 | 0.043 |
QOL overall* | 86.43±13.32; [8.2, 100] | 86.78±13.30; [8.2, 100] | 81.79±12.77; [43.6, 100] | 1.43 to 9.46 | 0.013 |
VAS* | 79.61±16.62; [15, 100] | 80.12±16.50; [15, 100] | 72.56±16.80; [40, 100] | 3.29 to 12.17 | 0.004 |
*, statistically significant (P≤0.05). PH, pulmonary hypertension; QOL, quality of life; VAS, visual analogue scale; SD, standard deviation; CI, confidence interval.
Discussion
To date, this is the largest cross-sectional, single-center study to investigate psychosocial implications of PH-CHD. The present study provides important information about the QOL of adults with PH-CHD that should be taken into account in the complex care of this special group of patients.
Although targeted PH treatment has become a cornerstone in the management of affected CHD patients (14), present findings indicate that their general well-being in terms of QOL remains markedly impaired. The study contributes to the paucity of knowledge on this topic by employing the EQ-5D-5L which allows a highly valid and reliable evaluation of QOL for both, clinical and research settings (12). Present findings provide evidence that patients with PH-CHD are at particularly high risk for a diminished QOL and major mental, psychosocial and physiological impairments. Physical impairment, struggle to cope with everyday life and debilitating psychiatric symptoms were the most commonly affected domains in patients, comparable to recently published results of an international multicentre study (12). Since diminished QOL was found to predict mortality in PH-CHD patients (14), there is an urgent need for optimisation of care in order to advance both, quality and lifespan in this particularly vulnerable patient population.
The two-fold measure of the EQ-5D-5L revealed differences in QOL values depending on the type of measurement applied. Apparently, the overall VAS score indicated significantly worse QOL scores than the descriptive value stemming from the specific factor descriptions. One explanation for this discrepancy could be due to differences in the QOL coverage of both measures (15). It can be assumed that the descriptive system encourages a patient to examine QOL from several angles while the VAS picks up a one-dimensional and therefore generic view of perceived somatic health restrictions imposed by PH. Therefore, the average reduction in VAS scores was considerably greater in PH-CHD than among CHD patients without PH.
Overall, however, it is noticeable, particularly on the basis of Figure 1, that patients with manifest PH-CHD have the lowest QOL across all five dimensions. This also becomes evident in the calculation of overall QOL.
Independent of the presence of PH, all included patients reported impairments mostly within the dimensions anxiety, depression (11.08%), pain and discomfort (11.03%). This is in line with a former large-scale study of Andonian et al. investigating 4,000 patients with CHD (15), as well as a study by Berghammer et al. (16), who found that ACHD present significant impairment in the perception of their physical and mental well-being. Accordingly, emotional distress as well as problems related to functional aspects (pain and discomfort) were higher in PH-CHD as compared to the general public per se. A further increased prevalence of depression and anxiety in PH-CHD patients has been well documented previously (17-19). Potential risk factors for the development of anxiety or depression in this patient population include socioeconomic factors, such as financial burden due to treatment or unemployment, as well as emotional burden due to the prognostic uncertainty and continuous deterioration of their condition (20). In addition, patients with PH showed significantly higher impairment in the domains of mobility, self-care and usual activities. These findings might be explained by functional restrictions, such as decreased exercise capacity, dyspnoea and limitations in day-to-day activities (8,21).
Limitations
To date, the present study represents the largest mono-center study to comprehensively assess QOL in PH-CHD patients. A representative comparison group was surveyed with the same assessment tools to offer a point of reference. However, some limitations must be considered when interpreting the current results.
First, the study was cross-sectional in nature and therefore depicts a snapshot of a patient’s health status. It not possible to draw conclusions about the etiology of psychological, psychosocial and physiological effects or the development of QOL in patients with or without PH-CHD. Since there is preliminary evidence on a continuous deterioration of QOL as the condition of PH progresses, longitudinal studies designs would be feasible to obtain a thorough understanding of the disease-related burden over time. Second, selection bias in respondents willing to participate appears unavoidable, such that more serious disease manifestations might be more (or less) frequent among non-responders. Third, patients with PH are significantly older than patients without PH. This condition is caused by the progressive character of the disease. Therefore, age might be an important and influencing factor on QOL besides the PH itself. Fourth, in future research, more psychosocial endpoints, such as depression, anxiety and overall emotional distress should be considered. Additionally, investigating more medical parameters, such as treatment and treatment duration, might add valuable insights on QOL in PH-CHD patients. Finally, the study was based on self-report outcomes and might be subject to recall and self-presentation bias.
Conclusions
PH is an often underestimated complication and sequel of a broad variety of CHD. Given the established negative consequences of PH on morbidity and mortality in ACHD, it is pivotal to identify unique psychosocial impairments and prevent further psychological and physical decline.
Patients would therefore benefit most from early interdisciplinary assessments and continuous health promotion, resource oriented counselling as routine component of a holistic approach to PH management.
Acknowledgments
We would like to thank Deutsche Herzstiftung e.V. for their ongoing support in research.
Funding: This research was funded by the German Heart Foundation (“Deutsche Herzstiftung e.V.”), grant number F-30-15, the patient organization “Herzkind e.V.” and Actelion Pharmaceuticals Germany GmbH, grant number MED-2015-495.
Footnote
Provenance and Peer Review: This article was commissioned by the editorial office, Cardiovascular Diagnosis and Therapy for the series “Current Management Aspects in Adult Congenital Heart Disease (ACHD): Part V”. The article has undergone external peer review.
Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://cdt.amegroups.com/article/view/10.21037/cdt-22-284/rc
Data Sharing Statement: Available at https://cdt.amegroups.com/article/view/10.21037/cdt-22-284/dss
Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://cdt.amegroups.com/article/view/10.21037/cdt-22-284/coif). The series “Current Management Aspects in Adult Congenital Heart Disease (ACHD): Part V” was commissioned by the editorial office without any funding or sponsorship. HK served as the unpaid Guest Editor of the series. The authors have no other 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) and approved by the local ethics committee of the Technical University Munich (157/16 S). All participants completed an informed consent form. Guidelines on GPP and all relevant data protection guidelines were followed.
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/.
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