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Reduced health-related quality of life in older patients with congenital heart disease: A cross sectional study in 2360 patients
International Journal of Cardiology 175 (2014) 358–362
Contents lists available at ScienceDirect
International Journal of Cardiology journal homepage: www.elsevier.com/locate/ijcard
Reduced health-related quality of life in older patients with congenital heart disease: A cross sectional study in 2360 patients Jan Müller ⁎, Anne Berner, Peter Ewert, Alfred Hager Department of Pediatric Cardiology and Congenital Heart Disease, Deutsches Herzzentrum München, Technische Universität München, Germany
a r t i c l e
i n f o
Article history: Received 25 September 2013 Received in revised form 6 May 2014 Accepted 9 June 2014 Available online 18 June 2014 Keywords: Congenital heart disease Quality of life Exercise capacity Adults
a b s t r a c t Objective: Health-related quality of life questionnaires are frequently used to involve patients' impressions and feelings in the outcome evaluation. In patients with congenital heart disease (CHD) methodological heterogeneities, assessment in different age and diagnostic groups led to controversial findings. This study aims to give a comprehensive answer to the health-related quality of life in patients with CHD. Patients and methods: From July 2001 to June 2013, 2360 patients (1058 female, 28.6 ± 11.2 years, range 14– 75 years) with various kinds of CHD underwent a quality of life assessment with the SF-36 questionnaire and underwent a cardiopulmonary exercise test as part of their routine follow-up. Results: Physical component summary score (PCS) develops from 96.1 %predicted in patients younger than 20 years, to 96.2 %predicted in patients aged 20 to 30 years, 92.3 %predicted in patients aged 30 to 40 years, and 92.6 %predicted in patients 40 years or older (r = −.114; p b .001). The decline was more prominent in the mental component summary score (MCS) declining from 104.1 %predicted in patients younger than 20 years, to 103.4 %predicted, 99.9 %predicted, and 97.5 %predicted (r = −.132; p b .001). Exercise capacity was impaired with 80.1 ± 23.0 %predicted and also declined slowly with age (r = −.084; p b .001). Conclusions: Health-related quality of life in patients with CHD is progressively reduced in older age-groups. The decline is small, but more prominent in the mental components. This should be considered in the interpretation of studies, and strategies have to be developed to reduce this effect in future. © 2014 Elsevier Ireland Ltd. All rights reserved.
1. Introduction Advances in diagnosis, surgical treatment and medical management have led to a dramatic increase in survival of infants and children with congenital heart disease (CHD). This resulted in a still increasing number of adolescents and adults with CHD [1]. As a result, the focus in long-term follow-up studies changed from a quantitative point of view on survival and redo procedures, to a more functional perspective involving hemodynamics, exercise performance and especially quality of life [2,3]. However, the concept of quality of life is in debate. There are several questionnaires: for healthy people and for patients; as well as generic and disease specific ones. In general, the more disease specific they are, the better is the sensitivity in treatment studies, but the more they leave the primary goal to measure quality of life. The disease specific instruments mainly ask for typical symptoms and resemble more a perceived health status than real quality of life which is defined as
⁎ Corresponding author at: Department of Pediatric Cardiology and Congenital Heart Disease, Deutsches Herzzentrum München, Technische Universität München, Lazarettstr. 36, D-80636 München, Germany. Tel.: + 49 89 1218 3009; fax: + 49 89 1218 3003. E-mail address: [email protected] (J. Müller).
http://dx.doi.org/10.1016/j.ijcard.2014.06.008 0167-5273/© 2014 Elsevier Ireland Ltd. All rights reserved.
“satisfaction with life” [4]. Generic multidimensional “health-related quality of life” (HRQoL) instruments are somewhere intermediate. They include domains that are a pure perceived health status, as well as domains closer to quality of life [5]. Therefore, we have chosen for such an instrument, the SF-36. In clinical outcome studies, it is an optimal addition to a cardiopulmonary exercise test (CPET). CPET objectively measures aerobic capacity which is considered the best substitute for cardiovascular fitness. On the other hand, the SF-36 covers physical, psychological, and social limitations as well as their impact on daily life. Whereas the domain of Physical Functioning as perceived health status correlates at least weakly with aerobic capacity [6], the selfreported domain of Mental Health closely resembles quality of life. Assessing HRQoL in patients with CHD is important and frequently used to involve patients in the process of decision making especially before high risk procedures to evaluate how much the patient feels limited by his/her cardiac condition, as well as in the outcome evaluation [7,8]. Also for prenatal counseling of future parents awaiting a child with a congenital heart defect, information regarding the patients short- and long-term HRQoL is of major interest for the decision whether or not to terminate the pregnancy [9]. Meanwhile, many studies have evaluated HRQoL of life in children, adolescents [10–13] or adults [3,14–20] in general, as well as with specific heart defects [11,21–26] or after a specific intervention [27–29].
J. Müller et al. / International Journal of Cardiology 175 (2014) 358–362
They found coping strategies, denial mechanisms and pathways like the sense of coherence [2,30] to mediate HRQoL. However, methodological heterogeneities, different age groups and specific congenital heart diseases led to controversial findings [7,8]. Moreover, the majority of those studies evaluated younger patient groups. Data from older patients reaching an age beyond forty years were missing. Therefore, this cross-sectional report aims to give a comprehensive answer to the HRQoL of patients with CHD with regard to their age and diagnosis. 2. Patients and methods 2.1. Study subjects We retrospectively analyzed our database of subjects referred for a cardiopulmonary exercise testing (CPET) in our institution from July 2001 to June 2013. All CPET were accompanied by a HRQoL assessment. Most patients were routinely recruited to CPET for evaluation of their functional status from our outpatient department and were not tested in cardiac decompensation to avoid a sampling bias towards a lower HRQoL. Less than 10% were inpatients, expecting surgery or heart catheterization. From 6542 examinations in our database, we excluded 1044 patients younger than fourteen, 411 healthy controls and 608 patients with mental retardation, syndromes or language barriers (Fig. 1). During that period of time we also had 2199 follow-up examinations. Only the most recent examination was included in our statistical analysis. Finally 2360 patients (1058 female, 1302 males; 28.6 ± 11.2 years old) with a HRQoL assessment were included. According the disease severity classification of the ACC [31] the defects were mild in 328 patients, moderate in 633 patients and complex in 1138 patients. The missing 261 patients with miscellaneous CHD were not assigned to the ACC groups. The detailed assignments to the diagnostic groups are presented in Table 1. 2.2. Health-related quality of life (HRQoL) The medical outcome study 36 item short form (SF-36) was used. It has an acceptable internal consistency and has proven useful in various specialties of medicine without any bias for symptoms of a specific disease [32,33]. The SF-36 measures eight health constructs with scores ranging from 0 (worst) to 100 (best) with two to 10 items per construct
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and one single item about health transition. The German version of the self-report form with a window of four weeks was used. Individual ageand sex-related reference values were drawn from the German evaluation study [32,33]. All values are presented in percentage of the predicted reference (%predicted). The scores of HRQoL (0–100) are only displayed in the supplemental material 1 and 2.
2.3. Cardiopulmonary exercise test (CPET) All patients underwent a symptom limited cardiopulmonary exercise test on a bicycle ergometer in upright position as previously described [11]. In short, after a 3 minute rest to define baseline, patients had a 3 minute warm-up without load, followed by a ramp wise increase of load with 10, 15, 20, or 30 W/min depending on the expected individual physical capacity estimated by the investigator. With this protocol a cycling duration of about 8 to 12 min after warm-up should be reached. The end of the CPET was marked by symptom limitation and was followed by a 5-minute recovery period, with the first 2–3 minute cycling with minimal load and 2 minute rest. The exercise test featured a breath-by-breath gas exchange analysis using a metabolic chart (Vmax 229, SensorMedics, Viasys Healthcare, Yorba Linda, California). Peak oxygen uptake (V˙O2) was defined as the highest mean uptake of any 30-second time interval during exercise. Reference values for age, body mass, body height, and gender, expressed in “% predicted” were calculated like previously described [30].
2.4. Data analyses All descriptive data were expressed as mean ± standard deviation. First, actual HRQoL scores were compared with the individual reference values by a paired t-test. After that only the values in %predicted were used for furtzer analyses. For the primary research question, whether there is a decline in HRQoL with proceeding age, Pearson's correlation was calculated to find associations between age, the physical and mental component summary of HRQoL and finally exercise capacity. Differences in between the diagnostic subgroups were tested with a one-way analysis of variance with Bonferroni post-hoc test. All analyses were performed using SPSS 21.0 software (IBM Inc, Armonk, New York, USA). P-values b0.05 in a two-sided analysis were considered significant.
Fig. 1. Patient inclusion.
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J. Müller et al. / International Journal of Cardiology 175 (2014) 358–362
Table 1 Study subjects, physical component summary, mental component summary and peak oxygen uptake according to diagnostic subgroups. Diagnosis
Cyanotic Fontan circulation TGA (Rastelli & CCTGA) TGA (Senning & Mustard) TGA (Arterial Switch) Tetralogy of Fallot Ebstein anomaly PS/PR Coarctation of the aorta Aortic stenosis Isolated shunt Miscellaneous Total p-values⁎
n
112 149 106 214 59 399 128 144 206 295 287 261 2360
Sex
Age
Physical component summary
Mental component summary
Peak oxygen uptake
♀/♂
Mean ± SD
(SF-36; %predicted)
(SF-36; %predicted)
(%predicted)
55/57 68/81 44/62 85/129 19/40 193/206 76/52 59/85 76/130 77/218 175/112 131/130 1058/1302 b.001
35.5 ± 26.5 ± 30.0 ± 28.8 ± 18.3 ± 28.9 ± 39.2 ± 28.6 ± 26.9 ± 26.9 ± 29.8 ± 25.2 ± 28.6 ± b.001
80.4 ± 18.0 92.7 ± 13.2 95.7 ± 12.6 95.0 ± 15.3 99.4 ± 8.8 94.6 ± 14.4 91.5 ± 19.3 96.2 ± 14.6 98.8 ± 12.0 97.9 ± 13.2 94.9 ± 15.4 101.7 ± 17.7 94.8 ± 15.0 b.001
100.9 ± 19.6 104.2 ± 17.5 104.0 ± 17.5 103.3 ± 17.5 106.7 ± 11.7 102.9 ± 17.0 96.8 ± 22.9 103.3 ± 17.0 102.3 ± 18.2 101.9 ± 17.5 98.0 ± 19.4 94.9 ± 14.9 101.9 ± 18.1 b.001
44.7 ± 63.5 ± 73.6 ± 72.2 ± 91.1 ± 78.6 ± 73.0 ± 87.5 ± 89.6 ± 91.8 ± 86.3 ± 84.8 ± 80.0 ± b.001
11.4 8.3 13.0 6.4 3.7 10.5 15.4 11.9 9.5 9.9 12.6 10.4 11.2
14.8 17.7 20.8 17.3 16.9 19.4 21.5 21.4 21.5 21.0 20.5 22.4 23.0
TGA = transposition of the great arteries, CCTGA = congenital corrected transposition of the great arteries, PS = pulmonary stenosis, PI = pulmonary insufficiency. Significant values are displayed in bold italic. ⁎ Differences in between the diagnosis are tested with a one-way analysis of variance.
3. Results 3.1. Health-related quality of life (HRQoL) In general, HRQoL was quite normal in patients with CHD when comparing all patients' mental component summary with the reference data (101.9 ± 18.1 %predicted; T = 5.1, df = 2359, p b .001, Table 1). In the physical component summary there was significant reduction (94.8 ± 15.0 %predicted; T = − 16.5, df = 2359, p b .001).
Males reported on a higher physical (male: 95.4 ± 13.7 %pred. vs. female: 94.0 ± 16.5 %pred; T = 2.2, df = 2359, p = .029) and woman on higher mental HRQoL components (male: 101.4 ± 16.4 %pred. vs. female: 102.5 ± 20.1 %pred.; T = −1.5, df = 2359, p = .149). Regarding the diagnostic subgroups there were significant differences both in physical HRQoL (F = 13.6, df = 2359, p b .001) and mental HRQoL (F = 3.1, df = 2359, p b .001, Table 1). Especially cyanotic patients showed significant reduction in physical HRQoL in comparison to the other diagnostic subgroups (Supplement 3), whereas in the
Fig. 2. Health related quality of life as physical (a) and mental (b) component summary scores (SF-36), and peak oxygen uptake (c) in %predicted in the 2360 patients with congenital heart disease according to the different age groups.
J. Müller et al. / International Journal of Cardiology 175 (2014) 358–362
mental HRQoL there was no consistent pattern of one group performing better or worse than the others (Supplement 4). Looking in the age groups there was a continuous decline in both, the perceived physical (r = − .114; p b .001) and mental HRQoL components (r = − .132; p b .001). (Fig. 2, Table 2). There were no gender effects on those declines. Detailed diagnose related and age related raw values for all subscales of the SF-36, as well as physical and mental component summary are presented in the online supplement (Supplement 1 & 2). 3.2. Exercise capacity Peak oxygen uptake was reduced to 27.9 ± 9.9 ml/min/kg or 80.0 ± 23.0 %predicted. Peak oxygen uptake declined slowly even when expressed as %pred. with age (r = −.084; p b .001) (Fig. 2). There was also a moderate association of peak oxygen uptake %predicted to the physical (r = .360; p b .001) and a slight association to the mental component (%predicted) of HRQoL (r = − .060; p = .004) (Table 2). 4. Discussion HRQoL is increasingly reduced in higher age-groups. This reduction is small, but more prominent in the mental components of HRQoL. This comprehensive study gives a broad overview regarding the physical and mental components of HRQoL in patients with CHD measured with a generic instrument compared to reference data [32,33]. Our results outline the pitfall of age and heterogeneity in the several published studies of patients with CHD. When looking on different diagnostic subgroups and different age groups, HRQoL could be either higher or lower than expected as it is represented by our data in the present study. This is especially shown in the more mental component of HRQoL with its more pronounced continuous decline with advancing age. This decline is also present in the physical components but less pronounced. Thus when looking on our data it is more likely to find a reduced HRQoL in older age-groups of patients with CHD which is in good agreement with Bruto et al. [25,26]. But it is not the only misinterpretation with regard to age. HRQoL data varies also in-between the different diagnostic subgroups of patients with CHD. This could be a reason why Mokhles et al. [26] found no substantial decrease in the HRQoL of older age groups because they only examine patients with right-ventricular-outflow-tract reconstruction. Studies looking on cyanotic patients [17,21,25] will measure reduced HRQoL in comparison to reports that aimed on non-cyanotic, and thus, more vital patients [15,22]. Especially Bruto et al. [25] found a diminished HRQoL in cyanotic patients and that current cyanosis emerged as an important factor on HRQoL.
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We only could speculate that the coping strategies, denial mechanisms, family involvement and other pathways that are used to obtain the overall good HRQoL in this cohort could be better applied earlier in life and the effects slowly diminish, when patients become aware of their limitations and restrictions in daily life. This might change their self-perception to a more realistic interpretation of their physical abilities. Another explanation for a more realistic self-perception in older years could be the increasing number of sequels that appear in later life. While most of the children suffer few sequels in their adolescence, young adults were already more confronted with exercise impairment [34–37] and arrhythmias [38], and also more diagnostic procedures, redo-operations, electrophysologic procedure, or medical treatment affecting their HRQoL. However, it cannot be ruled out in the interpretation of the current cross-sectional data, that those patients, that are older now, experienced a less sophisticated medical management in the past and, indeed, have a worse clinical condition. In this study, the declining trend in the HRQoL seems to be very slow. But this trend might be positively biased since two third of our patient cohort was younger than 30 years. Life expectancy in patients with CHD is less in comparison to the overall population. Thus a survival bias must be assumed as patients in worse condition are less likely to reach older age groups [35]. Therefore, a more progressive decline in HRQoL has to be expected for the individual patient. However, this can only be shown in a longitudinal study design in the future, when the life expectancy continues to increase and probably patients with CHD will reach even the geriatric age group. Nevertheless, our data should motivate us, not only to improve the cardiac function, but also to pay attention to the psychological needs of these patients. In addition, we have to include the patients' feelings and impressions to our medical management and to refrain high-risk procedures with questionable improvements especially in older patients with a fairly good quality of life. 5. Conclusion HRQoL in patients with CHD is increasingly reduced in higher agegroups. This decline is small, but more prominent in the mental dimensions that more closely resemble the true quality of life. This should not be neglected in the clinical management of the aging population also in patients with CHD. This can only be achieved by an interdisciplinary approach with nurses, medical doctors and psychologists in the clinical setting, and more family enrolment in the home-based setting. The defect-specific HRQoL values in the Supplement can be used as references. Conflict of interest No conflict of interest.
Table 2 Study subjects, physical component summary, mental component summary and peak oxygen uptake according to age-groups. Age
Younger 20 years 20–30 years 30–40 years 40 years or older Total p-values⁎
n
603 877 505 375 2360
Sex
Physical component summary
Mental component summary
Peak oxygen uptake
♀/♂
(SF-36, %predicted)
(SF-36, %predicted)
(%predicted)
216/387 392/485 241/264 209/166 1058/1302 b.001
96.1 ± 96.2 ± 92.5 ± 92.6 ± 94.8 ± b.001
104.1 ± 14.5 103.4 ± 18.6 99.9 ± 18.7 97.5 ± 21.7 101.9 ± 18.1 b.001
82.1 80.5 78.2 78.0 80.0 .009
−.114 (b.001) −1.6 %pred.
−.132 (b.001) −2.2 %pred.
−.084 (.001)
.360 (b.001)
.060 (.004)
–
Pearson correlation to age Pearson's R (p) Decline per decade Pearson correlation to peak oxygen uptake (%predicted) Pearson's R (p) Significant values are displayed in bold. ⁎ Differences in between the age-groups are tested with a one-way analysis of variance.
11.3 13.3 16.8 20.5 15.0
± ± ± ± ±
21.0 22.8 24.0 24.6 23.0
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J. Müller et al. / International Journal of Cardiology 175 (2014) 358–362
Funding None. Appendix A. Supplementary data Supplementary data to this article can be found online at http://dx. doi.org/10.1016/j.ijcard.2014.06.008. References [1] Moons P, Bovijn L, Budts W, Belmans A, Gewillig M. Temporal trends in survival to adulthood among patients born with congenital heart disease from 1970 to 1992 in Belgium. Circulation 2010;122:2264–72. [2] Apers S, Moons P, Goossens E, et al. Sense of coherence and perceived physical health explain the better quality of life in adolescents with congenital heart disease. Eur J Cardiovasc Nurs 2013;12(5):475–83. [3] Ehlert N, Hess J, Hager A. Shifts in exercise capacity are not reported adequately in patients with congenital heart disease. Congenit Heart Dis 2012;7:448–54. [4] Moons P. Why call it health-related quality of life when you mean perceived health status? Eur J Cardiovasc Nurs 2004;3:275–7. [5] Smith KW, Avis NE, Assmann SF. Distinguishing between quality of life and health status in quality of life research: a meta-analysis. Qual Life Res 1999;8:447–59. [6] Gratz A, Hess J, Hager A. Self-estimated physical functioning poorly predicts actual exercise capacity in adolescents and adults with congenital heart disease. Eur Heart J 2009;30:497–504. [7] Fteropoulli T, Stygall J, Cullen S, Deanfield J, Newman SP. Quality of life of adult congenital heart disease patients: a systematic review of the literature. Cardiol Young 2013;23(4):473–85. [8] Latal B, Helfricht S, Fischer JE, Bauersfeld U, Landolt MA. Psychological adjustment and quality of life in children and adolescents following open-heart surgery for congenital heart disease: a systematic review. BMC Pediatr 2009;9:6. [9] Arya B, Glickstein JS, Levasseur SM, Williams IA. Parents of children with congenital heart disease prefer more information than cardiologists provide. Congenit Heart Dis 2013;8:78–85. [10] Spijkerboer AW, Utens EM, Bogers AJ, Helbing WA, Verhulst FC. A historical comparison of long-term behavioral and emotional outcomes in children and adolescents after invasive treatment for congenital heart disease. J Pediatr Surg 2008;43:534–9. [11] Müller J, Christov F, Schreiber C, Hess J, Hager A. Exercise capacity, quality of life, and daily activity in the long-term follow-up of patients with univentricular heart and total cavopulmonary connection. Eur Heart J 2009;30:2915–20. [12] de Koning WB, van Osch-Gevers M, Ten Harkel AD, et al. Follow-up outcomes 10 years after arterial switch operation for transposition of the great arteries: comparison of cardiological health status and health-related quality of life to those of the a normal reference population. Eur J Pediatr 2008;167:995–1004. [13] Neuner B, Busch MA, Singer S, et al. Sense of coherence as a predictor of quality of life in adolescents with congenital heart defects: a register-based 1-year follow-up study. J Dev Behav Pediatr 2011;32(4):316–27. [14] Müller J, Hess J, Hager A. Daily physical activity in adults with congenital heart disease is positively correlated with exercise capacity but not with quality of life. Clin Res Cardiol 2012;101:55–61. [15] Loup O, von Weissenfluh C, Gahl B, Schwerzmann M, Carrel T, Kadner A. Quality of life of grown-up congenital heart disease patients after congenital cardiac surgery. Eur J Cardiothorac Surg 2009;36:105–11 [discussion 11]. [16] Immer FF, Althaus SM, Berdat PA, Saner H, Carrel TP. Quality of life and specific problems after cardiac surgery in adolescents and adults with congenital heart diseases. Eur J Cardiovasc Prev Rehabil 2005;12:138–43. [17] Lane DA, Lip GY, Millane TA. Quality of life in adults with congenital heart disease. Heart 2002;88:71–5.
[18] Müller J, Hess J, Hager A. General anxiety of adolescents and adults with congenital heart disease is comparable with that in healthy controls. Int J Cardiol 2013;165:142–5. [19] Müller J, Hess J, Hager A. Minor symptoms of depression in patients with congenital heart disease have a larger impact on quality of life than limited exercise capacity. Int J Cardiol 2012;154:265–9. [20] Moons P, Van Deyk K, De Bleser L, et al. Quality of life and health status in adults with congenital heart disease: a direct comparison with healthy counterparts. Eur J Cardiovasc Prev Rehabil 2006;13:407–13. [21] Müller J, Hess J, Hager A. Exercise performance and quality of life is more impaired in Eisenmenger syndrome than in complex cyanotic congenital heart disease with pulmonary stenosis. Int J Cardiol 2011;150:177–81. [22] Müller J, Hess J, Horer J, Hager A. Persistent superior exercise performance and quality of life long-term after arterial switch operation compared to that after atrial redirection. Int J Cardiol 2011;166:381–4. [23] Lambert LM, Minich LL, Newburger JW, et al. Parent- versus child-reported functional health status after the Fontan procedure. Pediatrics 2009;124: e942–9. [24] Meijboom F, Szatmari A, Deckers JW, et al. Long-term follow-up (10 to 17 years) after Mustard repair for transposition of the great arteries. J Thorac Cardiovasc Surg 1996;111:1158–68. [25] Bruto VC, Harrison DA, Fedak PW, Rockert W, Siu SC. Determinants of healthrelated quality of life in adults with congenital heart disease. Congenit Heart Dis 2007;2:301–13. [26] Mokhles MM, van de Woestijne PC, de Jong PL, et al. Clinical outcome and healthrelated quality of life after right-ventricular-outflow-tract reconstruction with an allograft conduit. Eur J Cardiothorac Surg 2011;40:571–8. [27] Müller J, Kühn A, Vogt M, Schreiber C, Hess J, Hager A. Improvements in exercise performance after surgery for Ebstein anomaly. J Thorac Cardiovasc Surg 2011;141:1192–5. [28] Dua JS, Cooper AR, Fox KR, Graham Stuart A. Exercise training in adults with congenital heart disease: feasibility and benefits. Int J Cardiol 2010;138:196–205. [29] Moons P, Barrea C, Suys B, et al. Improved perceived health status persists three months after a special sports camp for children with congenital heart disease. Eur J Pediatr 2006;165:767–72. [30] Müller J, Hess J, Hager A. Sense of coherence, rather than exercise capacity, is the stronger predictor to obtain health-related quality of life in adults with congenital heart disease. Eur J Prev Cardiol 2013. http://dx.doi.org/10.1177/ 2047487313481753. [31] Warnes CA, Liberthson R, Danielson GK, et al. Task force 1: the changing profile of congenital heart disease in adult life. J Am Coll Cardiol 2001;37:1170–5. [32] Bullinger M. German translation and psychometric testing of the SF-36 Health Survey: preliminary results from the IQOLA Project. International Quality of Life Assessment. Soc Sci Med 1995;41:1359–66. [33] Bullinger M, Kirchberger I. SF-36, Fragebogen zum Gesundheitszustand, Handanweisung. 1st ed. Göttingen: Hogrefe; 1998. [34] Fredriksen PM, Veldtman G, Hechter S, et al. Aerobic capacity in adults with various congenital heart diseases. Am J Cardiol 2001;87:310–4. [35] Diller GP, Dimopoulos K, Okonko D, et al. Exercise intolerance in adult congenital heart disease: comparative severity, correlates, and prognostic implication. Circulation 2005;112:828–35. [36] Giardini A, Hager A, Lammers AE, et al. Ventilatory efficiency and aerobic capacity predict event-free survival in adults with atrial repair for complete transposition of the great arteries. J Am Coll Cardiol 2009;53:1548–55. [37] Fredriksen PM, Pettersen E, Thaulow E. Declining aerobic capacity of patients with arterial and atrial switch procedures. Pediatr Cardiol 2009;30:166–71. [38] Khairy P, Aboulhosn J, Gurvitz MZ, et al. Arrhythmia burden in adults with surgically repaired tetralogy of Fallot: a multi-institutional study. Circulation 2010;122:868–75.
Contents lists available at ScienceDirect
International Journal of Cardiology journal homepage: www.elsevier.com/locate/ijcard
Reduced health-related quality of life in older patients with congenital heart disease: A cross sectional study in 2360 patients Jan Müller ⁎, Anne Berner, Peter Ewert, Alfred Hager Department of Pediatric Cardiology and Congenital Heart Disease, Deutsches Herzzentrum München, Technische Universität München, Germany
a r t i c l e
i n f o
Article history: Received 25 September 2013 Received in revised form 6 May 2014 Accepted 9 June 2014 Available online 18 June 2014 Keywords: Congenital heart disease Quality of life Exercise capacity Adults
a b s t r a c t Objective: Health-related quality of life questionnaires are frequently used to involve patients' impressions and feelings in the outcome evaluation. In patients with congenital heart disease (CHD) methodological heterogeneities, assessment in different age and diagnostic groups led to controversial findings. This study aims to give a comprehensive answer to the health-related quality of life in patients with CHD. Patients and methods: From July 2001 to June 2013, 2360 patients (1058 female, 28.6 ± 11.2 years, range 14– 75 years) with various kinds of CHD underwent a quality of life assessment with the SF-36 questionnaire and underwent a cardiopulmonary exercise test as part of their routine follow-up. Results: Physical component summary score (PCS) develops from 96.1 %predicted in patients younger than 20 years, to 96.2 %predicted in patients aged 20 to 30 years, 92.3 %predicted in patients aged 30 to 40 years, and 92.6 %predicted in patients 40 years or older (r = −.114; p b .001). The decline was more prominent in the mental component summary score (MCS) declining from 104.1 %predicted in patients younger than 20 years, to 103.4 %predicted, 99.9 %predicted, and 97.5 %predicted (r = −.132; p b .001). Exercise capacity was impaired with 80.1 ± 23.0 %predicted and also declined slowly with age (r = −.084; p b .001). Conclusions: Health-related quality of life in patients with CHD is progressively reduced in older age-groups. The decline is small, but more prominent in the mental components. This should be considered in the interpretation of studies, and strategies have to be developed to reduce this effect in future. © 2014 Elsevier Ireland Ltd. All rights reserved.
1. Introduction Advances in diagnosis, surgical treatment and medical management have led to a dramatic increase in survival of infants and children with congenital heart disease (CHD). This resulted in a still increasing number of adolescents and adults with CHD [1]. As a result, the focus in long-term follow-up studies changed from a quantitative point of view on survival and redo procedures, to a more functional perspective involving hemodynamics, exercise performance and especially quality of life [2,3]. However, the concept of quality of life is in debate. There are several questionnaires: for healthy people and for patients; as well as generic and disease specific ones. In general, the more disease specific they are, the better is the sensitivity in treatment studies, but the more they leave the primary goal to measure quality of life. The disease specific instruments mainly ask for typical symptoms and resemble more a perceived health status than real quality of life which is defined as
⁎ Corresponding author at: Department of Pediatric Cardiology and Congenital Heart Disease, Deutsches Herzzentrum München, Technische Universität München, Lazarettstr. 36, D-80636 München, Germany. Tel.: + 49 89 1218 3009; fax: + 49 89 1218 3003. E-mail address: [email protected] (J. Müller).
http://dx.doi.org/10.1016/j.ijcard.2014.06.008 0167-5273/© 2014 Elsevier Ireland Ltd. All rights reserved.
“satisfaction with life” [4]. Generic multidimensional “health-related quality of life” (HRQoL) instruments are somewhere intermediate. They include domains that are a pure perceived health status, as well as domains closer to quality of life [5]. Therefore, we have chosen for such an instrument, the SF-36. In clinical outcome studies, it is an optimal addition to a cardiopulmonary exercise test (CPET). CPET objectively measures aerobic capacity which is considered the best substitute for cardiovascular fitness. On the other hand, the SF-36 covers physical, psychological, and social limitations as well as their impact on daily life. Whereas the domain of Physical Functioning as perceived health status correlates at least weakly with aerobic capacity [6], the selfreported domain of Mental Health closely resembles quality of life. Assessing HRQoL in patients with CHD is important and frequently used to involve patients in the process of decision making especially before high risk procedures to evaluate how much the patient feels limited by his/her cardiac condition, as well as in the outcome evaluation [7,8]. Also for prenatal counseling of future parents awaiting a child with a congenital heart defect, information regarding the patients short- and long-term HRQoL is of major interest for the decision whether or not to terminate the pregnancy [9]. Meanwhile, many studies have evaluated HRQoL of life in children, adolescents [10–13] or adults [3,14–20] in general, as well as with specific heart defects [11,21–26] or after a specific intervention [27–29].
J. Müller et al. / International Journal of Cardiology 175 (2014) 358–362
They found coping strategies, denial mechanisms and pathways like the sense of coherence [2,30] to mediate HRQoL. However, methodological heterogeneities, different age groups and specific congenital heart diseases led to controversial findings [7,8]. Moreover, the majority of those studies evaluated younger patient groups. Data from older patients reaching an age beyond forty years were missing. Therefore, this cross-sectional report aims to give a comprehensive answer to the HRQoL of patients with CHD with regard to their age and diagnosis. 2. Patients and methods 2.1. Study subjects We retrospectively analyzed our database of subjects referred for a cardiopulmonary exercise testing (CPET) in our institution from July 2001 to June 2013. All CPET were accompanied by a HRQoL assessment. Most patients were routinely recruited to CPET for evaluation of their functional status from our outpatient department and were not tested in cardiac decompensation to avoid a sampling bias towards a lower HRQoL. Less than 10% were inpatients, expecting surgery or heart catheterization. From 6542 examinations in our database, we excluded 1044 patients younger than fourteen, 411 healthy controls and 608 patients with mental retardation, syndromes or language barriers (Fig. 1). During that period of time we also had 2199 follow-up examinations. Only the most recent examination was included in our statistical analysis. Finally 2360 patients (1058 female, 1302 males; 28.6 ± 11.2 years old) with a HRQoL assessment were included. According the disease severity classification of the ACC [31] the defects were mild in 328 patients, moderate in 633 patients and complex in 1138 patients. The missing 261 patients with miscellaneous CHD were not assigned to the ACC groups. The detailed assignments to the diagnostic groups are presented in Table 1. 2.2. Health-related quality of life (HRQoL) The medical outcome study 36 item short form (SF-36) was used. It has an acceptable internal consistency and has proven useful in various specialties of medicine without any bias for symptoms of a specific disease [32,33]. The SF-36 measures eight health constructs with scores ranging from 0 (worst) to 100 (best) with two to 10 items per construct
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and one single item about health transition. The German version of the self-report form with a window of four weeks was used. Individual ageand sex-related reference values were drawn from the German evaluation study [32,33]. All values are presented in percentage of the predicted reference (%predicted). The scores of HRQoL (0–100) are only displayed in the supplemental material 1 and 2.
2.3. Cardiopulmonary exercise test (CPET) All patients underwent a symptom limited cardiopulmonary exercise test on a bicycle ergometer in upright position as previously described [11]. In short, after a 3 minute rest to define baseline, patients had a 3 minute warm-up without load, followed by a ramp wise increase of load with 10, 15, 20, or 30 W/min depending on the expected individual physical capacity estimated by the investigator. With this protocol a cycling duration of about 8 to 12 min after warm-up should be reached. The end of the CPET was marked by symptom limitation and was followed by a 5-minute recovery period, with the first 2–3 minute cycling with minimal load and 2 minute rest. The exercise test featured a breath-by-breath gas exchange analysis using a metabolic chart (Vmax 229, SensorMedics, Viasys Healthcare, Yorba Linda, California). Peak oxygen uptake (V˙O2) was defined as the highest mean uptake of any 30-second time interval during exercise. Reference values for age, body mass, body height, and gender, expressed in “% predicted” were calculated like previously described [30].
2.4. Data analyses All descriptive data were expressed as mean ± standard deviation. First, actual HRQoL scores were compared with the individual reference values by a paired t-test. After that only the values in %predicted were used for furtzer analyses. For the primary research question, whether there is a decline in HRQoL with proceeding age, Pearson's correlation was calculated to find associations between age, the physical and mental component summary of HRQoL and finally exercise capacity. Differences in between the diagnostic subgroups were tested with a one-way analysis of variance with Bonferroni post-hoc test. All analyses were performed using SPSS 21.0 software (IBM Inc, Armonk, New York, USA). P-values b0.05 in a two-sided analysis were considered significant.
Fig. 1. Patient inclusion.
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Table 1 Study subjects, physical component summary, mental component summary and peak oxygen uptake according to diagnostic subgroups. Diagnosis
Cyanotic Fontan circulation TGA (Rastelli & CCTGA) TGA (Senning & Mustard) TGA (Arterial Switch) Tetralogy of Fallot Ebstein anomaly PS/PR Coarctation of the aorta Aortic stenosis Isolated shunt Miscellaneous Total p-values⁎
n
112 149 106 214 59 399 128 144 206 295 287 261 2360
Sex
Age
Physical component summary
Mental component summary
Peak oxygen uptake
♀/♂
Mean ± SD
(SF-36; %predicted)
(SF-36; %predicted)
(%predicted)
55/57 68/81 44/62 85/129 19/40 193/206 76/52 59/85 76/130 77/218 175/112 131/130 1058/1302 b.001
35.5 ± 26.5 ± 30.0 ± 28.8 ± 18.3 ± 28.9 ± 39.2 ± 28.6 ± 26.9 ± 26.9 ± 29.8 ± 25.2 ± 28.6 ± b.001
80.4 ± 18.0 92.7 ± 13.2 95.7 ± 12.6 95.0 ± 15.3 99.4 ± 8.8 94.6 ± 14.4 91.5 ± 19.3 96.2 ± 14.6 98.8 ± 12.0 97.9 ± 13.2 94.9 ± 15.4 101.7 ± 17.7 94.8 ± 15.0 b.001
100.9 ± 19.6 104.2 ± 17.5 104.0 ± 17.5 103.3 ± 17.5 106.7 ± 11.7 102.9 ± 17.0 96.8 ± 22.9 103.3 ± 17.0 102.3 ± 18.2 101.9 ± 17.5 98.0 ± 19.4 94.9 ± 14.9 101.9 ± 18.1 b.001
44.7 ± 63.5 ± 73.6 ± 72.2 ± 91.1 ± 78.6 ± 73.0 ± 87.5 ± 89.6 ± 91.8 ± 86.3 ± 84.8 ± 80.0 ± b.001
11.4 8.3 13.0 6.4 3.7 10.5 15.4 11.9 9.5 9.9 12.6 10.4 11.2
14.8 17.7 20.8 17.3 16.9 19.4 21.5 21.4 21.5 21.0 20.5 22.4 23.0
TGA = transposition of the great arteries, CCTGA = congenital corrected transposition of the great arteries, PS = pulmonary stenosis, PI = pulmonary insufficiency. Significant values are displayed in bold italic. ⁎ Differences in between the diagnosis are tested with a one-way analysis of variance.
3. Results 3.1. Health-related quality of life (HRQoL) In general, HRQoL was quite normal in patients with CHD when comparing all patients' mental component summary with the reference data (101.9 ± 18.1 %predicted; T = 5.1, df = 2359, p b .001, Table 1). In the physical component summary there was significant reduction (94.8 ± 15.0 %predicted; T = − 16.5, df = 2359, p b .001).
Males reported on a higher physical (male: 95.4 ± 13.7 %pred. vs. female: 94.0 ± 16.5 %pred; T = 2.2, df = 2359, p = .029) and woman on higher mental HRQoL components (male: 101.4 ± 16.4 %pred. vs. female: 102.5 ± 20.1 %pred.; T = −1.5, df = 2359, p = .149). Regarding the diagnostic subgroups there were significant differences both in physical HRQoL (F = 13.6, df = 2359, p b .001) and mental HRQoL (F = 3.1, df = 2359, p b .001, Table 1). Especially cyanotic patients showed significant reduction in physical HRQoL in comparison to the other diagnostic subgroups (Supplement 3), whereas in the
Fig. 2. Health related quality of life as physical (a) and mental (b) component summary scores (SF-36), and peak oxygen uptake (c) in %predicted in the 2360 patients with congenital heart disease according to the different age groups.
J. Müller et al. / International Journal of Cardiology 175 (2014) 358–362
mental HRQoL there was no consistent pattern of one group performing better or worse than the others (Supplement 4). Looking in the age groups there was a continuous decline in both, the perceived physical (r = − .114; p b .001) and mental HRQoL components (r = − .132; p b .001). (Fig. 2, Table 2). There were no gender effects on those declines. Detailed diagnose related and age related raw values for all subscales of the SF-36, as well as physical and mental component summary are presented in the online supplement (Supplement 1 & 2). 3.2. Exercise capacity Peak oxygen uptake was reduced to 27.9 ± 9.9 ml/min/kg or 80.0 ± 23.0 %predicted. Peak oxygen uptake declined slowly even when expressed as %pred. with age (r = −.084; p b .001) (Fig. 2). There was also a moderate association of peak oxygen uptake %predicted to the physical (r = .360; p b .001) and a slight association to the mental component (%predicted) of HRQoL (r = − .060; p = .004) (Table 2). 4. Discussion HRQoL is increasingly reduced in higher age-groups. This reduction is small, but more prominent in the mental components of HRQoL. This comprehensive study gives a broad overview regarding the physical and mental components of HRQoL in patients with CHD measured with a generic instrument compared to reference data [32,33]. Our results outline the pitfall of age and heterogeneity in the several published studies of patients with CHD. When looking on different diagnostic subgroups and different age groups, HRQoL could be either higher or lower than expected as it is represented by our data in the present study. This is especially shown in the more mental component of HRQoL with its more pronounced continuous decline with advancing age. This decline is also present in the physical components but less pronounced. Thus when looking on our data it is more likely to find a reduced HRQoL in older age-groups of patients with CHD which is in good agreement with Bruto et al. [25,26]. But it is not the only misinterpretation with regard to age. HRQoL data varies also in-between the different diagnostic subgroups of patients with CHD. This could be a reason why Mokhles et al. [26] found no substantial decrease in the HRQoL of older age groups because they only examine patients with right-ventricular-outflow-tract reconstruction. Studies looking on cyanotic patients [17,21,25] will measure reduced HRQoL in comparison to reports that aimed on non-cyanotic, and thus, more vital patients [15,22]. Especially Bruto et al. [25] found a diminished HRQoL in cyanotic patients and that current cyanosis emerged as an important factor on HRQoL.
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We only could speculate that the coping strategies, denial mechanisms, family involvement and other pathways that are used to obtain the overall good HRQoL in this cohort could be better applied earlier in life and the effects slowly diminish, when patients become aware of their limitations and restrictions in daily life. This might change their self-perception to a more realistic interpretation of their physical abilities. Another explanation for a more realistic self-perception in older years could be the increasing number of sequels that appear in later life. While most of the children suffer few sequels in their adolescence, young adults were already more confronted with exercise impairment [34–37] and arrhythmias [38], and also more diagnostic procedures, redo-operations, electrophysologic procedure, or medical treatment affecting their HRQoL. However, it cannot be ruled out in the interpretation of the current cross-sectional data, that those patients, that are older now, experienced a less sophisticated medical management in the past and, indeed, have a worse clinical condition. In this study, the declining trend in the HRQoL seems to be very slow. But this trend might be positively biased since two third of our patient cohort was younger than 30 years. Life expectancy in patients with CHD is less in comparison to the overall population. Thus a survival bias must be assumed as patients in worse condition are less likely to reach older age groups [35]. Therefore, a more progressive decline in HRQoL has to be expected for the individual patient. However, this can only be shown in a longitudinal study design in the future, when the life expectancy continues to increase and probably patients with CHD will reach even the geriatric age group. Nevertheless, our data should motivate us, not only to improve the cardiac function, but also to pay attention to the psychological needs of these patients. In addition, we have to include the patients' feelings and impressions to our medical management and to refrain high-risk procedures with questionable improvements especially in older patients with a fairly good quality of life. 5. Conclusion HRQoL in patients with CHD is increasingly reduced in higher agegroups. This decline is small, but more prominent in the mental dimensions that more closely resemble the true quality of life. This should not be neglected in the clinical management of the aging population also in patients with CHD. This can only be achieved by an interdisciplinary approach with nurses, medical doctors and psychologists in the clinical setting, and more family enrolment in the home-based setting. The defect-specific HRQoL values in the Supplement can be used as references. Conflict of interest No conflict of interest.
Table 2 Study subjects, physical component summary, mental component summary and peak oxygen uptake according to age-groups. Age
Younger 20 years 20–30 years 30–40 years 40 years or older Total p-values⁎
n
603 877 505 375 2360
Sex
Physical component summary
Mental component summary
Peak oxygen uptake
♀/♂
(SF-36, %predicted)
(SF-36, %predicted)
(%predicted)
216/387 392/485 241/264 209/166 1058/1302 b.001
96.1 ± 96.2 ± 92.5 ± 92.6 ± 94.8 ± b.001
104.1 ± 14.5 103.4 ± 18.6 99.9 ± 18.7 97.5 ± 21.7 101.9 ± 18.1 b.001
82.1 80.5 78.2 78.0 80.0 .009
−.114 (b.001) −1.6 %pred.
−.132 (b.001) −2.2 %pred.
−.084 (.001)
.360 (b.001)
.060 (.004)
–
Pearson correlation to age Pearson's R (p) Decline per decade Pearson correlation to peak oxygen uptake (%predicted) Pearson's R (p) Significant values are displayed in bold. ⁎ Differences in between the age-groups are tested with a one-way analysis of variance.
11.3 13.3 16.8 20.5 15.0
± ± ± ± ±
21.0 22.8 24.0 24.6 23.0
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