The association of nocturia with sleep disorders and metabolic and chronic pulmonary conditions: data derived from the polysomnographic evaluations of 730 patients.

AIM

To evaluate the prevalence of nocturia among different degrees of obstructive sleep apnea (OSA) and its association with various clinical conditions.

MATERIALS AND METHODS

In 730 OSA patients, the prevalence and frequency of nocturia was determined, and the association of nocturia with clinical and laboratory variables such as the apnea-hypopnea index (AHI), apnea duration, and minimum oxygen saturation and clinical conditions such as diabetes mellitus, coronary heart disease, and chronic obstructive pulmonary disease (COPD) was determined.

RESULTS

The overall prevalence of nocturia (≥2 wakes/night) was 50.9%. Prevalences ofnocturia in simple snoring and mild, moderate, and severe OSA patients were 40.6%, 44.4%, 58.6%, and 57.1%, respectively (P < 0.005). The frequency of nocturia significantly increases with the severity of OSA (1.4 ± 1.0 wakes/night in mild OSA vs. 2.0 ? 1.4 wakes/night in severe OSA, P = 0.001). Age, AHI, average oxygen saturation, and presence of diabetes mellitus, hypertension, and COPD were found to be significant risk factors associated with nocturia (P <0.001).

CONCLUSION

The frequency of nocturia increases as the severity of OSA increase. The increased prevalence of nocturia in patients with OSA, diabetes mellitus, hypertension, and COPD indicates the complex physiological background of this bothersome urologic symptom.