Depression in hemodialysis patients: the role of dialysis shift

OBJECTIVE: Depression is the most important neuropsychiatric complication in chronic kidney disease because it reduces quality of life and increases mortality. Evidence demonstrating the association between dialysis shift and depression is lacking; thus, obtaining such evidence was the main objective of this study. METHOD: This cross-sectional study included patients attending a hemodialysis program. Depression was diagnosed using Beck's Depression Inventory. Excessive daytime sleepiness was evaluated using the Epworth Sleepiness Scale. RESULTS: A total of 96 patients were enrolled (55 males, age 48 +/- 14 years). Depression and excessive daytime sleepiness were observed in 42.7% and 49% of the patients, respectively. When comparing variables among the three dialysis shifts, there were no differences in age, dialysis vintage, employment status, excessive daytime sleepiness, hemoglobin, phosphorus levels, or albumin levels. Patients in the morning shift were more likely to live in rural areas (p<0.0001), although patients in rural areas did not have a higher prevalence of depression (p = 0.30). Patients with depression were more likely to be dialyzed during the morning shift (p = 0.008). Independent risk factors for depression were age (p<0.03), lower levels of hemoglobin (p<0.01) and phosphorus (p<0.01), and dialysis during the morning shift (p = 0.0009). The hospitalization risk of depressive patients was 4.5 times higher than that of nondepressive patients (p<0.008). CONCLUSION: These data suggest that depression is associated with dialysis shift, higher levels of phosphorus, and lower levels of hemoglobin. The results highlight the need for randomized trials to determine whether this association occurs by chance or whether circadian rhythm disorders may play a role.