Warmer weather ups risk of urinary tract infection in women

A recent study suggests that the prior week’s temperature affects the incidence of urinary tract infection (UTI) in women, with results indicating warmer weather as a risk factor for UTIs. Moreover, the morbidity attributable to UTIs may increase as temperatures rise.

“The incidence of UTIs is seasonal, peaking in summer months,” the authors said, noting that one potential reason for this seasonality was warmer weather.

The risk of UTIs among women treated in outpatient settings in a dose-response fashion increased with warmer weather. The incidence of UTIs rose by 20 percent to 30 percent on days when the prior week’s average temperature was between 25 and 30 °C relative to when the prior week’s temperature was 5 to 7.5 °C.

The authors identified all UTI cases located in approximately 400 metropolitan statistical areas in the contiguous US between 2001 and 2015 using the Truven Health MarketScan databases. Overall, 167,078,882 person-years were included in this dataset, with 15,876,030 UTI events identified by ICD-9 code 599.0.

Weather data for each metropolitan statistical area and date were obtained from the National Centers for Environmental Information. The authors computed mean temperature during the period 0 to 7 days prior to UTI diagnosis and used a quasi-Poisson generalized linear model.

The number of UTIs each day in a metropolitan statistical area in each age group was the primary outcome. Covariates considered were as follows: age group, day of week, year, and temperature during the previous 7 days.