Serum apelin is associated with affective disorders in peritoneal dialysis patients

Depression and anxiety are prevalent affective disorders in peritoneal dialysis (PD) patients. Recent research has proposed a potential role of apelinergic system in pathogenesis of depression. The present study aimed to evaluate the frequency of depression and anxiety and their potential relation with serum apelin levels among PD patients.

A total of 40 PD patients were enrolled into the study. Depressive symptoms and anxiety were assessed with the Beck's Depression Inventory and the Beck's Anxiety Inventory. Serum apelin-12 levels were measured by immunoenzymatic assays using commercially available ELISA kit for standard human apelin.

Of the patients, 16 (40%) had depression, 20 (50%) had anxiety. The patients with depression and anxiety had a significantly longer time on dialysis (p < 0.001 for both), significantly higher serum apelin (p < 0.001 for both) and C-reactive protein levels (p < 0.001 for both) than those without depression and anxiety. In multivariate analysis, serum apelin was the only parameter associated independently with depression and anxiety scores.

A substantial number of PD patients had depression and anxiety. Increased levels of serum apelin may constitute a significant independent predictor of development of depression and anxiety in PD patients.