Economic assessment of three antimicrobial therapies for uncomplicated urinary tract infection in women.

ABSTRACT

This retrospective cohort study used North Carolina Medicaid paid-claims data to assess clinical and economic outcomes of treatments for urinary tract infection (UTI). The study population comprised female Medicaid recipients, between 15 and 64 years of age, with a paid claim filed for a primary diagnosis of UTI or acute UTI from January 1 to June 30, 1994, who were treated with ciprofloxacin, nitrofurantoin, or trimethoprim/sulfamethoxazole (TMP/SMZ). Patients had follow-up for 6 months after the primary diagnosis. Patients who did not receive further treatment for UTI with 1 of the 3 drugs within 30 days after initial treatment were assumed to be cured. Costs were measured as the sum of reimbursements for UTI-related medical services and drug treatments. Outcomes for 409 patients were assessed. Cure rates of initial treatment with ciprofloxacin, nitrofurantoin, and TMP/SMZ were 81%, 88%, and 93%, respectively. Cost-effectiveness ratios of initial treatment with the 3 drugs were $150.80, $81.20, and $69.00, respectively. When efficacy rates generated from published randomized clinical studies were applied, cost-effectiveness ratios for the 3 drugs were $130.96, $86.17, and $72.00, respectively. A decision model of treatment pattern and associated costs is presented. Several patient variables indicate that the ciprofloxacin group included more severe cases of UTI than did the other groups. Study limitations, confounders, and future research suggestions are discussed. Our results show that treatment for >7 days results in a better cure rate regardless of the drug used than does treatment for < or =7 days and that TMP/SMZ is the most cost-effective of the 3 drugs for UTI or acute UTI.