title: Cranberry juice fails to prevent recurrent urinary tract infection: results from a randomized placebo-controlled trial.
abstract: BACKGROUND
  A number of observational studies and a few small or open randomized clinical trials suggest that the American cranberry may decrease incidence of recurring urinary tract infection (UTI).
  
  
  METHODS
  We conducted a double-blind, placebo-controlled trial of the effects of cranberry on risk of recurring UTI among 319 college women presenting with an acute UTI. Participants were followed up until a second UTI or for 6 months, whichever came first. A UTI was defined on the basis of the combination of symptoms and a urine culture positive for a known uropathogen. The study was designed to detect a 2-fold difference between treated and placebo groups, as was detected in unblinded trials. We assumed 30% of participants would experience a UTI during the follow-up period.
  
  
  RESULTS
  Overall, the recurrence rate was 16.9% (95% confidence interval, 12.8%-21.0%), and the distribution of the recurrences was similar between study groups, with the active cranberry group presenting a slightly higher recurrence rate (20.0% vs 14.0%). The presence of urinary symptoms at 3 days, 1-2 weeks, and at ≥ 1 month was similar between study groups, with overall no marked differences. CONCLUSIONS.: Among otherwise healthy college women with an acute UTI, those drinking 8 oz of 27% cranberry juice twice daily did not experience a decrease in the 6-month incidence of a second UTI, compared with those drinking a placebo.
authors.affiliation: Department of Epidemiology, Center for Molecular and Clinical Epidemiology of Infectious Diseases, University of Michigan School of Public Health, Ann Arbor, Michigan 48109–2029, USA.
authors.forename: Cibele
authors.initials: C
authors.lastname: Barbosa-Cesnik
authors.forename: Morton B
authors.initials: MB
authors.lastname: Brown
authors.forename: Miatta
authors.initials: M
authors.lastname: Buxton
authors.forename: Lixin
authors.initials: L
authors.lastname: Zhang
authors.forename: Joan
authors.initials: J
authors.lastname: DeBusscher
authors.forename: Betsy
authors.initials: B
authors.lastname: Foxman
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D001688:Biological Products / Q000008:administration & dosage*; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D010919:Placebos / Q000008:administration & dosage; D055502:Secondary Prevention; D016896:Treatment Outcome; D014552:Urinary Tract Infections / Q000517:prevention & control*; D029799:Vaccinium macrocarpon / Q000737:chemistry*; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D001688:Biological Products; D010919:Placebos