Risks of Nocturia in Patients with Chronic Kidney Disease—Do the Metabolic Syndrome and its Components Matter?

Abstract

We evaluate the risk factors for nocturia in patients with chronic kidney disease, and determine whether the metabolic syndrome and its components aggravate nocturia in these patients. We enrolled patients with chronic kidney disease who had regular followup at nephrology clinics, and excluded from study those patients undergoing dialysis, and those with neurogenic bladder or active urinary tract infection. Patients were asked to complete a questionnaire including medical history, clinical parameters and times of nocturnal voids in the last month. Laboratory parameters were checked when the questionnaire was completed. Clinically significant nocturia was defined as voiding 2 or more times per night. The metabolic syndrome was defined according to the ATP III (National Cholesterol Education Program Adult Treatment Panel III) guidelines. Chronic kidney disease was divided into 5 stages (based on National Kidney Foundation guidelines). Multivariate logistic regression was used to evaluate the risk factors for clinically significant nocturia. A total of 202 men and 234 women were eligible for analysis (mean age 68.4 years). The prevalence rate of clinically significant nocturia in patients with chronic kidney disease was 64.0%. Statistically significant risk factors for clinically significant nocturia were patient age (OR 1.02, 95% CI 1.003-1.04) and chronic kidney disease stage (OR 1.47, 95% CI 1.19-1.81) but not gender. Although 53.9% of our patients with chronic kidney disease had the metabolic syndrome, the metabolic syndrome (adjusted OR 0.96, 95% CI 0.64-1.44) and its components had no significant correlations with clinically significant nocturia. Clinically significant nocturia is prevalent in patients with chronic kidney disease, and the severity increased with chronic kidney disease stage and patient age. Contrary to previous reports, the metabolic syndrome did not increase the risk of clinically significant nocturia in patients with chronic kidney disease.