Effect of Cranberry on Urinary Tract Infection Risk: A Meta-Analyses (P06-116-19)

Abstract

ObjectivesCranberry (Vaccinium spp.) has been advocated for maintaining healthy urinary tract function in women; however, the effect in other populations is controversial. The aim of this meta-analysis was to evaluate cranberry intake and the risk of uncomplicated urinary tract infection (UTI) and some categories of complicated UTI in otherwise healthy populations. MethodsMEDLINE, EMBASE, Cochrane, and Web of Science were systematically searched, and studies screened and extracted using a predefined strategy by two independent investigators. Discrepancies were resolved by discussion with a third investigator. Meta-analysis was performed using RevMan (version 5.3.5, Cochrane, UK). Heterogeneity was assessed with both I2 and the chi-square tests. A low to moderate (I2 < 50%) heterogeneity was found; thus, fixed-effect model using the Mantel-Haenszel method were used to estimate the risk ratio (RR). ResultsA total of 16 studies were included in the quantitative analysis. Pooled RR estimates for the seven studies on healthy, non-pregnant women (RR = 0.76 [95% CI: 0.63–0.91]) suggest that cranberry may reduce the risk for UTI recurrence in this population, consistent with previous meta-analyses. Meta-analysis also suggests lower UTI risk with cranberries in children based on four studies (RR = 0.58 [95% CI: 0.41–0.83]). Only two studies in pregnant women were identified and these were both performed by the same research group. RR estimates obtained for healthy, pregnant women (RR = 0.87 [95% CI: 0.37–2.04]) were not significant. The RR estimate for elderly/institutionalized adults was also not significant (RR = 0.81 [95% CI: 0.48–1.35]), but the three studies in this evaluation included data combined from heterogeneous populations having immune, neurological, and/or physical dysfunction with data from healthy people. Therefore, these findings do not reflect data in the generally healthy elderly population. ConclusionsMeta-analysis of studies investigating cranberry and UTI risk suggests that cranberries may be useful in reducing the risk of uncomplicated UTI recurrence in healthy, non-pregnant women and children. More research is needed on the effect of cranberry on UTI risk in pregnant women and generally healthy elderly/institutionalized adults before firm conclusions can be made. Funding SourcesOcean Spray.