A RANDOMISED clinical trial conducted across 99 primary care centres in the UK has found that D-mannose, a supplement often touted for its potential in preventing urinary tract infections (UTI), does not live up to its promise. The study sought to determine whether daily intake of D-mannose, over a 6-month period, could reduce the occurrence of medically attended UTIs.
The study itself was comprised of 598 females (mean [range] age: 58 [18–93] years), 303 of whom were randomised to D-mannose (50.7%) and 295 to placebo (49.3%). Participants were recruited between 28th March 2019–31st January 2020, with 6 months of follow-up. The primary outcome measure was the proportion of females experiencing at least one further episode of clinically suspected UTI for which they contacted ambulatory care within the 6-month study period.
Despite promising previous research, results showed no significant difference between the D-mannose and placebo groups in terms of the proportion of females experiencing medically attended UTIs; the proportion contacting ambulatory care with a clinically suspected UTI was 150 of 294 (51.0%) in the D-mannose group and 161 of 289 (55.7%) in the placebo group (risk difference: -5%; 95% confidence interval: -13–3%; P=0.26). Secondary outcome measures, including symptom duration, antibiotic use, and time to the next UTI, also failed to show any notable disparities between the two groups.
These findings suggest that D-mannose should not be recommended as a prophylactic measure for recurrent UTIs in females receiving primary care. The study emphasises the need for evidence-based approaches in managing UTIs, and highlights the importance of rigorously evaluating purported remedies before their widespread adoption in clinical practice.
Reference
Hayward G et al. D-mannose for prevention of recurrent urinary tract infection among women. JAMA Intern Med, 2024;DOI:10.1001/jamainternmed.2024.0264.
