Nocturic frequency is related to severity of obstructive sleep apnea, improves with continuous positive airways treatment

Objective: The purpose of this study was to determine the relationship between nocturia and obstructive sleep apnea (OSA), and the effect of continuous positive airways pressure (CPAP) therapy on nocturic frequency. Study design: This was a retrospective review of sleep studies including patients with and without evidence of OSA, before and during CPAP treatment (where relevant). Chi-squared tests compared nocturia prevalence according to sleep diagnosis, logistic regression determined predictors of nocturia, and regression analyses determined predictors of nocturic frequency. Results: In 196 eligible studies, predictors of nocturia included increasing age and diabetes mellitus; nocturia was equally likely to occur in patients with and without OSA. In patients with OSA and nocturia, nocturic frequency was related to age, diabetes, and severity of OSA (P < .001). Patients with OSA and nocturia who were treated with CPAP demonstrated a significant decrease in nocturic frequency (P < .001). Conclusion: OSA severity predicts nocturic frequency. The role of testing in the triage of patients with nocturia remains to be determined.