UC Irvine

OBJECTIVE: Maintenance hemodialysis (MHD) patients have a high prevalence of anxiety and depression and decreased daily physical activity (DPA) and exercise capacity. Because affective disorders may affect DPA and physical performance, we investigated possible relationships between anxiety or depression and DPA and physical performance in relatively healthy MHD patients. DESIGN AND METHODS: This cross-sectional study included 72 relatively healthy MHD patients and 39 normal adults. DPA was measured for 7 days with an Actigraph Activity Monitor®. Physical performance was assessed using the 6-minute walk (6-MWT), sit-to-stand (STS), and stair-climbing tests. Subjects completed the Beck Anxiety Inventory (BAI), the Beck Depression Inventory-II (BDI), and the Hospital Anxiety and Depression Scale (HADS). Main outcome measures were physical activity counts (expressed as vector magnitude), in the 6-MWT, STS, stair-climbing test, BAI, BDI, and HADS scores. RESULTS: Anxiety and depression by BAI and BDI were identified in 43% and 33% of MHD patients and 2.5% and 5% of normals, respectively (P < .0001 for each comparison). MHD patients without anxiety or depression had decreased DPA and physical performance compared with normals, indicating that these disorders were also independent of anxiety or depression. MHD patients with anxiety and depression generally had the most impaired DPA and physical performance. Higher BAI and BDI scores were each associated with impaired physical performance. In fully adjusted analyses, DPA in MHD patients was negatively correlated with the BDI (r = -0.33, P = .01) but not with the BAI. DPA on the day of hemodialysis (P = .01), and day 1 (P = .03) and day 2 (P = .03) after dialysis each correlated negatively with degree of depression by BDI. In MHD patients, BAI was negatively correlated with 6-MWT (P = .03) and STS (P = .04). CONCLUSIONS: In relatively healthy adult MHD patients, anxiety and depression are common and are associated with impaired physical performance. There was a trend toward stronger negative associations between BDI scores and DPA than between BAI scores and DPA.