Associations between genetics, medical status, physical exercise and psychological well-being in adults with cystic fibrosis

BACKGROUND Cystic fibrosis (CF) is the most common autosomal recessive, life-shortening disease among people of European origin. Type of genetic mutation and regular physical exercise has an impact on clinical outcome. This cross-sectional study explores the associations between genetics, medical status, physical exercise and psychological well-being in adult patients with CF. METHODS Adult patients with CF (N=68; mean age: 32.2; range 18-67 years; 46% women) completed the Cystic Fibrosis Questionnaire-Revised and Hospital Anxiety Depression Scale. Measures about lung function/forced expiratory volume in 1 s per cent predicted, body mass index, physical working capacity, immunoglobulin G, CF Transmembrane Conductance Regulator (CFTR) mutations, and physical exercise were obtained. structural equation modelling was used to fit models to data. RESULTS A cftr gene mutation×age interaction effect indicates a psychological disadvantage increasing with age of having more severe CFTR mutations; >65% of the effect is mediated by medical status. Physical exercise has a positive effect on psychological well-being, but >75% of the effect is mediated by medical status. CONCLUSIONS Psychological well-being decreases with age in patients with more severe cftr mutations, to a large extent due to a parallel deterioration of medical status. Physical exercise has a positive effect on psychological well-being if resulting in better health only. To manage the complexity of these patients' needs, the CF-care should emphasise a holistic approach and offer individualised exercise/treatment programmes and psychological competence.