Overactive bladder in diabetes: a peripheral or central mechanism?

To study diabetic cystopathy with reference to overactive bladder (OAB).

We retrospectively analyzed diabetic cystopathy in our digitized database that comprised 2300 case records, including data from a lower urinary tract symptoms questionnaire, data from a urodynamic study, and data from neurological examinations.

Diabetic cystopathy was seen in 4% of cases (84 cases): 58 males, 26 females; mean age, 60.8 years; duration of diabetes, 143.5 months; HbA1C, 7.7 %. In addition to large post-void residual and decreased sensation, OAB, detrusor overactivity (DO), and increased bladder sensation were seen in 55%, 42%, and 14%, respectively. The frequency of DO in patients with increased bladder sensation was 58%. DO increased with age, but not with the duration of diabetes. A brain MRI was performed in 32 cases. The frequency of multiple cerebral infarction (MCI) in patients with DO was 76.5%. The remaining 23.5% of patients with DO had no MCI, and the remaining 42% with increased bladder sensation had no DO.

OAB commonly occurs in diabetic cystopathy. Both central and peripheral mechanisms are involved, e.g., MCI due to diabetic cerebral vasculopathy for the DO, and, to a lesser extent, peripheral nerve irritation for the DO and increased bladder sensation.