Prevention of urinary tract infections in nursing homes: lack of evidence-based prescription?

Background: Urinary tract infections (UTIs, including upper and lower symptomatic) are the most common infections in nursing homes and prevention may reduce patient suffering, antibiotic use and resistance. The spectre of agents used in preventing UTIs in nursing homes is scarcely documented and the aim of this study was to explore which agents are prescribed for this purpose. Methods: We conducted a one-day, point-prevalence study in 44 Norwegian nursing homes during April-May 2006. Nursing home residents prescribed any agent for UTI prophylaxis were included. Information recorded was type of agent and dose, patient age and gender, together with nursing home characteristics. Appropriateness of prophylactic prescribing was evaluated with references to evidence in the literature and current national guidelines. Results: The study included 1473 residents. 18% (n = 269) of the residents had at least one agent recorded as prophylaxis of UTI, varying between 0-50% among the nursing homes. Methenamine was used by 48% of residents prescribed prophylaxis, vitamin C by 32%, and cranberry products by 10%. Estrogens were used by 30% but only one third was for vaginal administration. Trimethoprim and nitrofurantoin were used as prophylaxis by 5% and 4%, respectively. Conclusions: The agents frequently prescribed to prevent UTIs in Norwegian nursing homes lack documented efficacy including methenamine and vitamin C. Recommended agents like trimethoprim, nitrofurantoin and vaginal estrogens are infrequently used. We conclude that prescribing of prophylactic agents for UTIs in nursing homes is not evidence-based.