The implications of somatic symptom disorder on the impairment of daily life are greater in post-COVID syndrome than in asthma or COPD - results of a cross-sectional study in a rehabilitation clinic

The aim was to compare the relationship between somatic symptom disorder (SSD), anxiety, depression, clinical symptoms, and daily life impairment (DLI) in post-COVID syndrome (PCS), asthma and chronic obstructive pulmonary disease (COPD). In a cross-sectional study, 371 patients (161 PCS, 121 asthma, 89 COPD) of a pulmonary rehabilitation clinic received the questionnaires PHQ-15 (Patient Health Questionnaire-15) and SSD-12 (Somatic Symptom Disorder-12) to determine SSD, GAD-7 (Generalized Anxiety Disorder-7) to determine anxiety disorder, and PHQ-9 (Patient Health Questionnaire-9) to determine depression. Lung function was estimated using whole-body plethysmography. Predictors for DLI were assessed by regression models and ROC analyses. Association of SSD with DLI was stronger in PCS (odds ratio 13.8; 95% confidence interval 1.7-109.9) than in asthma (8.5; 2.4-30.1), and was not significant in COPD (1.9; 0.5-7.5). In asthma and COPD, strongest predictors were GAD-7 (15.0; 1.9-116.8) and PHQ-9 (8.9; 1.1-71.8), respectively. Diffusion capacity was predictive in COPD (0.947; 0.916-0.979) and asthma (0.967; 0.943-0.993), but not in PCS. To conclude, SSD appears to have greater impact on DLI in PCS than asthma or COPD patients. This should be recognized appropriately during rehabilitation. Furthermore, increased psychological comorbidity should also be considered and adequately treated in asthma and COPD if necessary.