Determinants of the quality of life of patients with congenital heart disease.

OBJECTIVE: The improvement of the quality of life of chronically ill patients has become an important goal in treatment. However, it is seldom taken into account that many other factors, in addition to somatic factors, have an influence on the quality of life of patients. Using patients with congenital heart defects as an example, we examined the relative significance of biological factors, compared to psychological and social factors, for the various quality of life dimensions. RESEARCH DESIGN AND METHODS: One hundred and eleven patients (aged 33+/-12 years) with different degrees of cardiac dysfunction were examined (NYHA 0: 2 I: 56, II: 38, III: 13, IV: 2). All patients for whom there was no contra-indication underwent a treadmill ergometry in order to determine their level of cardiopulmonary functioning (peak oxygen consumption: VO2max). All patients were asked to fill out questionnaires concerning their quality of life (WHOQOL-Bref), their cardiac complaints (Giessener Complaint Questionnaire GBB), their personality traits (Giessen Test GTS), and the social support they experience (Social Support Questionnaire SOZU-k22). The data were analyzed using a linear structural equation model (SEM).
RESULTS: In all aspects but the social domain, the HRQL of CgHD patients was significantly diminished compared to the normal population. The SEM proposed was valid, showing good indices of fit (chi2 = 1.18; p = 0.55; AGFI = 0.92). The level of cardiopulmonary functioning was most significant for the reporting of specific cardiac complaints (beta = -28) and for the physical component of the general HRQL (beta = 32), although the former was also influenced by a depressed disposition (beta = -0.20) and the extent of social support experienced (beta = 0.18). The objective findings, however, had virtually no individual significance for the psychological (beta = 0.09) and social domains (beta = -0.02). These HRQL domains are primarily influenced by depressive personality traits (beta= -26/-0.16) and the social support experienced (beta = 0.51/0.51).
CONCLUSIONS: The patient's organic dysfunction primarily determines illness-specific complaints but has little relevance for the psychological and social aspects of the HRQL. These aspects are predominantly determined by the patient's depressive disposition and by the experienced social support. A successful therapy should therefore take biological as well as psycho-social determinants of the quality of life into account.