The impact of prolonged air pollution exposure on urinary tract and male reproductive system infections: insights from a large-scale prospective cohort study

To assess the link between long-term air pollution exposure and the risk of urinary tract infections (UTIs) and male reproductive system infections (MRSIs), which significantly impact incidence and quality of life. This prospective cohort study included 375,833 participants from the UK Biobank. We used a Cox proportional hazards model, adjusting for covariates, to evaluate the association between exposure to air pollutants (PM2.5, PMcoarse, PM10, NO2, and NOx) and the risk of UTIs and MRSIs. Nonlinear exposure-response relationships were assessed with restricted cubic splines, and subgroup analyses were conducted to examine potential effect modifiers. Over a median follow-up of 12.4 years, 26,279 new UTIs and 3,545 MRSI cases were detected. It was found that there were significant connections between the likelihood of developing UTIs and being exposed to PM2.5 (hazard ratios (HRs): 1.43, 95% confidence interval (CI): 1.34–1.53), PMcoarse (HR: 1.17, 95% CI: 1.08–1.27), PM10 (HR: 1.24, 95% CI: 1.15–1.34), NO2 (HR: 1.10, 95% CI: 1.08–1.12), and NOx (HR: 1.09, 95% CI: 1.07–1.11). Similar associations were found for MRSIs. Restricted cubic spline analyses revealed non-linear exposure-response relationships for all pollutants. The strength of these connections was validated through sensitivity analyses. Long-term exposure to air pollutants is associated with a higher risk of UTIs and MRSIs, emphasizing the urgent need to improve air quality to mitigate these health risks.