Is inflammation a new risk factor of depression in haemodialysis patients?

Prevalence of depression is high in patients with chronic kidney disease. Depression is associated with increased mortality and the higher rate of suicides in these patients. The aim of the study was to estimate the prevalence of depressive symptoms in haemodialyzed patients in Upper Silesia region of Poland and the possible role of inflammation in depression development.

Six hundred and ninety-seven haemodialyzed patients from 22 dialysis centres in Upper Silesia region of Poland were enrolled into the study. Mean age was 59.1 ± 0.5 years, and mean time of dialysis treatment was 3.6 ± 0.2 years. Each patient received 21-item Beck Depression Inventory (BDI) questionnaire for depression screening. Additional questions considering length of dialysis treatment, concomitant diseases and number of days spent in hospitals during the last year were also asked.

Depressive symptoms were found in 268 (38.6 %) patients. Patients with depressive symptoms when compared with the patients without them tended to have higher C-reactive protein plasma concentration (14.3 ± 1.3 vs. 11.1 ± 0.9 mg/l; p = 0.067) and were more often dialyzed with central catheter (27.6 vs. 18.2 %; p = 0.0042). During the last year, patients with depressive symptoms spent in hospitals more days than patients without depressive symptoms (24.3 vs. 15.3 days, respectively; p < 0.0001). Significant positive correlation between BDI score and C-reactive protein level (r = 0.1625; p = 0.001) was found both in univariate and multivariate analysis.

(1) Depressive symptoms are frequently found (38.6 %) in haemodialyzed patients in Upper Silesia part of Poland. (2) Catheter placement and inflammation seem to play an important role in the pathogenesis of depression in haemodialysis patients.