Daily physical activity in patients on chronic haemodialysis and its relation with fatigue and depressive symptoms

Objective Fatigue and depressed mood are considered main impediments to physical activity in haemodialysis (HD) patients. A better understanding of their interrelationships is crucial to develop effective therapies. Moreover, measurement of daily physical activity (DPA) in HD patients is tricky, as it is usually assessed by subjective self-report questionnaires. Therefore, we aimed to objectively measure sponteanous DPA with motion sensors and to explore its relation with fatigue and depressive symptoms. Methods DPA was assessed for seven consecutive days in 37 HD patients based on their daily step count measured with the SenseWear (TM) Armband. The Fatigue Severity Scale (FSS) and Beck Depression Inventory-II (BDI-II) were administered to evaluate fatigue and depressed mood. Results Median DPA was 2424 steps/day, (IQR:892-4545). In 81% of subjects, DPA felt within a sedentary lifestyle classification, as they made < 5.000 steps/day. DPA did not correlate with fatigue (r(s) = 0.04,p = 0.832), and did not significantly differ between patients categorized as clinically fatigued (n = 23, FSS >= 4) or not (n = 14, FSS < 4) (p = 0.654,d = 0.20). Although low-depressed subjects (n = 19, BDI-II <= 13) made on average 1.7 times more steps/day than high-depressed subjects (n = 18, BDI-II > 13) (p = 0.111,d = 0.60), depressive mood did also not correlate significantly with DPA (r(s) = - 0.23,p = 0.175). Conclusion Objective assessment of DPA with motion sensors is feasible in HD patients and allows identifying a sedentary lifestyle. Our results suggest that spontanous DPA is determined by age rather than by fatigue or mood.