Cranberry Products Don't Prevent UTIs
The researchers found no significant difference in the percent of women who had bacteriuria plus pyuria among those taking cranberry capsules or placebo.
HealthDay News — There is no significant difference in the presence of bacteriuria plus pyuria over one year among older women living in nursing homes receiving cranberry capsules versus a placebo pill, according to a study published online in the Journal of the American Medical Association. The research was published to coincide with the annual meeting of the Infectious Diseases Society of America (IDWeek), held from Oct 26 to 30 in New Orleans.
Manisha Juthani-Mehta, MD, an associate professor of medicine at the Yale School of Medicine in New Haven, Conn, and colleagues randomly assigned 185 female nursing home residents (average age was 86) to 2 oral cranberry capsules a day or placebo. Each capsule contained the equivalent of 20 oz of cranberry juice.
Among all the women, 31.4% had bacteriuria plus pyuria at the start of the study. 80% of the patients took the capsules as directed and 147 completed the one-year study. The researchers found no significant difference in the percent of women who had bacteriuria plus pyuria among those taking cranberry capsules or placebo (29.1 and 29.0%, respectively; odds ratio, 1.01; 95% confidence interval, 0.61 to 1.66; P = 0.98). There was also no significant difference in the number of urinary tract infections over the course of a year -- 10 episodes in the treatment group compared to 12 in the control group.
"Cranberry products have long been thought to prevent urinary tract infections, and many different cranberry products, including capsules, tablets and powders, are promoted for this purpose, but this study did not show that this product worked," Juthani-Mehta told HealthDay.
Cranberry and placebo capsules used in the study were manufactured and donated by Pharmatoka.
Juthani-Mehta M, Van Ness PH, Bianco L, et al. Effect of Cranberry Capsules on Bacteriuria Plus Pyuria Among Older Women in Nursing Homes. JAMA. 27 October 2016. doi:10.1001/jama.2016.16141