Purpose/Rationale: The Multicenter Assessment of Transdermal Therapy in Overactive Bladder with Oxybutynin (MATRIX) study evaluated long-term safety and patient outcomes in adults with overactive bladder (OAB) treated with transdermal oxybutynin. This analysis compares pad use and nocturia among study participants, before and after treatment.

Methodology: Participants in MATRIX, an open-label, multicenter, prospective study, were treated with transdermal oxybutynin* 3.9 mg/d (new patch applied every 3–4 days) for up to 6 months. The impact of OAB on quality of life was evaluated at 3-month intervals using King's Health Questionnaire® (KHQ). Patients also rated overall OAB severity from 1 (no problems) to 6 (many severe problems). P values based on Kappa test for symmetry (paired categorical variables).

Results: MATRIX comprised 2508 women (mean age 61.4±14.7y; 41.1% working) and 369 men (mean age 69.6±13.1y; 23.6% working). At baseline, 46.4% of patients had OAB symptoms for ³4 years, 12.0%, for £1 year, and 57% had received prior OAB treatment. Approximately 78.2% rated overall severity ≥4, and 61.1% reported using on average ³1 pad daily. According to item responses from KHQ, most patients (97.5%) reported being affected by nocturia (80.8% moderately or a lot), and 89.9% stated bladder problems affected their sleep (51.9% often or all the time). By study end, the proportion of patients reporting pad use “often” or “all the time” decreased from 48% to 41.9%, while those needing to change wet underclothes “often” or “all the time” decreased from 51.1% to 28.6%. Patients reported significant (P<.0001) improvements from baseline to study end in nocturia (41% improved, 10.1% worsened) and sleep (38.4% improved; 10.0% worsened).

Conclusions: Treatment with transdermal oxybutynin is associated with improvement in nocturia as well as in the incidence of urinary leakage, and may decrease the need for pad use by patients with OAB.

*Oxytrol®, Watson Pharma, Corona, Calif.