Depression at Baseline Is an Independent Risk Factor for Cognitive Decline in Patients on Peritoneal Dialysis: A Multicenter Prospective Cohort Study

: Background:Depression has been recognized as a risk factor for cognitive impairment (CI) from cross-sectional datasets. This multicenter prospective study investigated the association between depression and cognitive decline in peritoneal dialysis (PD) patients.Methods:This multicenter prospective cohort study included 458 PD patients who were followed up for 2 years. The Modified Mini-Mental State Examination (3MS) was used for assessment of global cognitive function, Trail-Making Tests A and B for executive function, subtests of the Battery for the Assessment of Neuropsychological Status for immediate and delayed memory, visuospatial skill, and language ability. Depression was assessed using Zung's Self-Rating Depression Scale.Results:During the 2-year follow-up, patients with moderate/severe depression at baseline showed a significant decline in global cognitive function (80.5 ± 15.2 vs 76.6 ± 15.5, p = 0.008), while patients without depression or with mild depression kept a stable global cognitive function. In the meantime, patients without depression showed significant improvements in immediate memory, visuospatial skill, and language ability. However, no significant improvement in these parameters was shown in depression groups. In multivariable linear regression analysis, depression at baseline was a significant predictor of worsening global cognitive function, whether depression was analyzed as a continuous variable (odds ratio [OR] = -0.14, 95% confidence interval [CI] -0.27, -0.01, p = 0.031) or a rank variable (OR = -1.88, 95% CI -3.30, -0.45, p = 0.010). Moreover, higher depression score or more severe depression degradation was significantly associated with decline of immediate memory, delayed memory, and language skill.Conclusion:Depression was a significant risk factor for worsening of CI in PD patients.