Management of Refractory Overactive Bladder with Incontinence -A Novel Approach

BACKGROUND Overactive bladder (OAB) syndrome is a chronic, debilitating syndrome, symptoms include urgency with or without urge incontinence (UI), frequency, and nocturia. First line management includes life style modification and anticholinergics. In patients with unsatisfactory symptomatic improvement, anticholinergic dose can be increased for therapeutic benefit but with increased side effects. Severe symptoms of overactive bladder (OAB) with urge incontinence (WET) not responding to standard dose of anticholinergics, addition of mirabegron (β3 - adrenoceptor agonist) may improve the symptoms. We wanted to evaluate the efficacy, safety, tolerance and side effects of combination therapy-mirabegron (50 mg) and solifenacin (5 mg) (anticholinergic) compared with monotherapy of either, solifenacin or mirabegron for a period of 6 weeks in patients with over active bladder (OAB) with urge incontinence, remaining incontinent after tolterodine (4 mg) (anticholinergic). METHODS Study was conducted on 70 patients from October to December 2019, in Andhra Medical College, Visakhapatnam (Andhra Pradesh), which is a tertiary care centre. 40 patients were selected based on inclusion and exclusion criteria. 30 patients were female and 10 patients were male with a median age of 55 years. Group A (n=10) mirabegron 50 mg/day, Group B (n=10) solifenacin 5 mg/day Group C (n=20) mirabegron 50 mg plus solifenacin 5 mg/day. Efficacy was measured as a change from base line to the end of treatment (EOT), in the mean number of incontinent episodes per 24 hrs and micturition per 24 hrs. Safety assessments included Treatment Emergent Adverse Events (TEAEs), blood pressure, pulse rate, post-void residual volume (PVR), laboratory and electrocardiography (ECG) parameters. RESULTS Combination therapy provides greater amelioration of symptoms in over active bladder (OAB) with incontinence (wet) compared to monotherapy. Combination therapy is well tolerated with acceptable safety profile. CONCLUSIONS Patients suffering from over active bladder (OAB) with incontinence, combination therapy with solifenacin and mirabegron provides satisfactory therapeutic effect and improved quality of life (QOL), within short period of time (4-6 Weeks). Increased risk of side effects associated with dose escalation of solifenacin from 5 mg to 10 mg can be avoided.