Microvascular Complications and Prevalence of Nocturia in Japanese Patients With Type 2 Diabetes Mellitus: The Dogo Study.

Objective: To evaluate the association between microvascular complications and nocturia among Japanese patients with type 2 diabetes mellitus.

Methods: Study subjects were 731 Japanese patients with type 2 diabetes mellitus. A self-administered questionnaire was used to collect information on the variables under study. Study subjects were considered to have nocturia if they answered "once or more" to the question: "How many times do you typically wake up to urinate from sleeping at night until waking in the morning?" Diabetic neuropathy was diagnosed if the patients showed two or more of the following three characteristics: neuropathic symptoms, the absence of the Achilles reflex, or abnormal vibration perception. Diabetic nephropathy was defined as positive when the estimated glomerular filtration rate was <30 mL/min/1.73 m(2) and/or the urine albumin-to-creatinine ratio was ≥34 mg/mmol creatinine. Several ophthalmology specialists were responsible for evaluating diabetic retinopathy. Adjustment was made for sex, age, body mass index, duration of diabetes mellitus, current smoking, current drinking, hypertension, stroke, ischemic heart disease, and glycated hemoglobin.

Results: The prevalence of nocturia was 80.4%. Diabetic retinopathy was independently positively associated with nocturia (adjusted odds ratio 2.39 [95% confidence interval: 1.08-6.11]). In contrast, diabetic nephropathy or diabetic neuropathy was not associated with nocturia.

Conclusion: In Japanese patients with type 2 diabetes mellitus, only diabetic retinopathy was independently positively associated with nocturia.