PDE5 plays a role in the smooth muscle cells (SMCs) of the bladder, and the endothelium of blood vessels as it affects cGMP which is the primary regulator of smooth muscle contractility. We evaluated the efficacy of daily low-dose tadalafil versus tolterodine for treatment of overactive bladder (OAB) symptoms in women.
90 female patient, who had OAB s, were classified into Tadalafil 5 mg d-1 group, Tolterodine extended release 2 mg cap and a placebo group. Symptoms and complaints were evaluated prior to the treatment (baseline) and at 3 months post-treatment. Full detailed voiding history was taken from the patients participating in the study regarding the overactive bladder symptoms and a 3- day micturition diary (3-d MD), Overactive bladder symptoms score (OABSS), Indevus Urgency severity scale, (IUSS) were fulfilled by the patient before and after treatment. Uroflowmetry and transabdominal ultrasound to measure post-voiding residual urine were done before treatment and at 3 months post-treatment. Treatment efficacy was measured by comparing the by comparing the data following a 3-month treatment period to the initial values. Efficacy measures included the number of micturitions per 24 hours (daytime frequency or nocturia) and the number of incontinence episodes per 24 hours.
There was no significant difference between tadalafil and tolterodine groups regarding post-treatment urgency. Also,there was no significant difference between tadalafil and tolterodine groups regarding post-treatment frequency. No statistically significant difference was reported between the 3 groups regarding post-treatment urge incontinence or nocturia. As regard post-treatment OABS score, it was significantly lower among patients who received tadalafil and tolterodine when compared with patients who received placebo (P< 0.001). Urgency, frequency, urge incontinence, and nocturia significantly reduced after treatment with tadalafil when compared with pre-treatment (P=< 0.001, < 0.001, < 0.001 and 0.004 respectively). Moreover, OABSS and IUSS significantly reduced after treatment with tadalafil when compared with pre-treatment (P< 0.001 and < 0.001 respectively).
Daily low-dose tadalafil is a satisfactory, effective treatment for female OABs with comparable results to tolterodine.