The Effect of Cranberry Juice Consumption on the Recurrence of Urinary Tract Infection: Relationship to Baseline Risk Factors

The objective of this study was to assess relationships between clinical predictors of urinary tract infection (UTI) and effects of cranberry juice consumption on recurrence in a post hoc analysis of a 24-week, randomized, double-blind, placebo-controlled, multicenter clinical trial in women with a recent history of UTI.Participants consumed a cranberry (n = 185) or placebo (n = 188) beverage (240 mL) daily. Odds ratios (OR) from 20 candidate predictor variables were evaluated in univariate analyses to assess clinical UTI incidence relationships in the placebo group. A multivariate logistic regression model was developed. The effects of cranberry juice consumption were evaluated in subsets categorized by the likelihood of a UTI event based on the prediction model.In the placebo group, the final multivariate regression model identified four variables associated with the odds for having ≥ 1 UTI: intercourse frequency ≥ 1 time during the prior 4 weeks (OR: 2.36; 95% confidence interval [CI]: 0.98, 5.71; p = 0.057), use of vasectomy or hormonal methods for contraception (OR: 2.58; 95% CI: 1.20, 5.58; p = 0.016), most recent UTI90 days prior to screening (OR: 2.28; 95% CI; 1.12, 4.67; p = 0.024), and living in France compared with the United States (OR: 0.17; 95% CI: 0.04, 0.79; p = 0.024). Three propensity categories were investigated (24-week probability10%, 10%-21%, and21%). Incidence rate ratios for the cranberry vs placebo groups were 0.76 (95% CI: 0.22, 2.60; p = 0.663) for those with10% probability, 0.73 (95% CI: 0.35, 1.53; p = 0.064) for those with 10% to 21% probability, and 0.58 (95% CI: 0.35, 0.97; p = 0.039) for those with21% probability.Results suggest that clinical predictors identify women with low and high risk of clinical UTI recurrence, which may be useful for design of clinical studies evaluating preventive therapies.