Association of a low protein diet with depressive symptoms and poor health-related quality of life in CKD

Objectives: A low protein diet (LPD) for chronic kidney disease (CKD) is a core dietary therapy to slow CKD progression. A study showed depressive symptoms are more common in populations with an LPD. In this cross-sectional study, we evaluated depressive symptoms and health-related quality of life (HRQOL) in patients with CKD. Methods: A total of 571 CKD patients were enrolled in this study. The LPD was defined with dietary protein intake <= 0.8 g/kg/day. We divided the CKD into mild CKD and advanced CKD according to severity, as well as diabetic kidney disease (DKD) and non-DKD according to DM. The logistic regression analysis was performed to evaluate the association between an LPD and depressive symptoms as well as HRQOL in CKD patients and each subgroup. Results: An LPD had significantly higher unadjusted Odds Ratio (OR) (1.81, [95% for Confidence Interval (CI), 1.18-2.76]) and multivariate-adjusted OR (1.80, [1.15-2.81]) for depressive symptoms. Moreover, an LPD showed significantly higher unadjusted OR (2.08, 1.44-3.01]) and multivariate OR (2.04, [1.38-3.02]) for poor HRQOL. In DKD subgroups, an LPD had a significant increase in unadjusted OR (2.00, [1.12-3.57]) and multivariate OR (1.99, [1.01-3.44]) for depressive symptoms. The advanced CKD group also showed that an LPD had significantly higher unadjusted OR (1.97, [1.13-3.42]) and multivariate OR (2.03, [1.12-3.73]) for depressive symptoms. Conclusions: An LPD for CKD patients was significantly associated with depressive symptoms and poor HRQOL. Subgroup analysis indicated that DKD and advanced CKD are more predisposed to depressive symptoms and poor HRQOL.