Retrospective evaluation of outcomes in patients with overactive bladder receiving tolterodine versus oxybutynin

Purpose. The frequency, relative risk, resource utilization, and costs related to comorbidities associated with overactive bladder (OAB) were studied. Methods. A retrospective analysis of patients with DAB who initiated treatment with tolterodine extended release (ER), oxybutynin ER, or oxybutynin immediate release (IR) between January 2001 and December 2002 was conducted to evaluate the frequency, relative risk, resource utilization, and costs related to three specific comorbidities associated with DAB: urinary tract infections (UTIs), depression, and fracture. Two patient cohorts (tolterodine ER versus oxybutynin ER and tolterodine ER versus oxybutynin IR) were matched on a 1:1 basis according to their propensity to receive a prescription for tolterodine ER. Results. The frequency and relative risk of UTIs were significantly lower in the tolterodine ER group than in the oxybutynin ER and oxybutynin IR groups. The relative risk of depression was also lower in the tolterodine ER group than the oxybutynin ER and oxybutynin IR groups; however, the differences were only significant in the tolterodine ER versus oxybutynin IR comparison. The utilization of UTI- and depression-related services and the number of antiinfective and antidepressant prescriptions were significantly lower in the tolterodine ER group than in the oxybutynin ER group. UTI- and depression-related costs were generally lower in the tolterodine ER group than in the oxybutynin ER or oxybutynin IR group. Conclusion. Treatment of DAB patients with tolterodine ER was associated with reduced frequency, relative risk, medical and pharmacy resource utilization, and incurred costs related to selected OAB-associated comorbidities compared with treatment with oxybutynin ER or oxybutynin IR.