Cranberry-containing products for prevention of urinary tract infections in susceptible populations: A systematic review and meta-analysis of randomized controlled trials
Journal
Archives of Internal Medicine
Journal Volume
172
Journal Issue
13
Pages
988-996
Date Issued
2012
Author(s)
Chen N.-C.
Yu P.-H.
Wu T.-Y.
Chen W.-T.
Abstract
Background: Urinary tract infection (UTI) is one of the most commonly acquired bacterial infections. Cranberry-containing products have long been used as a folk remedy to prevent UTIs. The aims of this study were to evaluate cranberry-containing products for the prevention of UTI and to examine the factors influencing their effectiveness.Methods: MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were systemically searched from inception to November 2011 for randomized controlled trials that compared prevention of UTIs in users of cranberry-containing products vs placebo or nonplacebo controls. There were no restrictions for language, population, or publication year. Results: Thirteen trials, including 1616 subjects, were identified for qualitative synthesis from 414 potentially relevant references; 10 of these trials, including a total of 1494 subjects, were further analyzed in quantitative synthesis. The random-effects pooled risk ratio (RR) for cranberry users vs nonusers was 0.62 (95% CI, 0.49-0.80), with amoderate degree of heterogeneity (I 2=43%) after the exclusion of 1 outlier study. On subgroup analysis, cranberry-containing products seemed to be more effective in several subgroups, including women with recurrent UTIs (RR, 0.53; 95% CI, 0.33-0.83) (I 2=0%), female populations (RR, 0.49; 95% CI, 0.34-0.73) (I 2=34%), children (RR, 0.33; 95% CI, 0.16-0.69) (I 2=0%), cranberry juice drinkers (RR, 0.47; 95% CI, 0.30-0.72) (I 2=2%), and subjects using cranberry-containing products more than twice daily (RR, 0.58; 95% CI, 0.40-0.84) (I 2=18%). Conclusions: Our findings indicate that cranberry-containing products are associated with protective effect against UTIs. However, this result should be interpreted in the context of substantial heterogeneity across trials. ? 2012 American Medical Association. All Rights Reserved.
Other Subjects
cranberry extract; placebo; Cochrane Library; cranberry juice; data analysis; data extraction; Embase; female; human; language; Medline; priority journal; quality control; quantitative analysis; randomized controlled trial (topic); review; systematic review; urinary tract infection; Beverages; Canada; Disease Susceptibility; Female; Finland; Food Habits; Food Handling; Great Britain; Humans; Italy; Male; Medicine, Traditional; Odds Ratio; Publication Bias; Randomized Controlled Trials as Topic; Recurrence; Sex Factors; United States; Urinary Tract Infections; Vaccinium macrocarpon
Type
review