Association between ambient temperature and atopic dermatitis in Lanzhou, China: a time series analysis

Many studies have explored the association between temperature and atopic dermatitis (AD); however, the results are inconsistent. We used a quasi-Poisson function fitted to a distributed lag nonlinear model (DLNM) to evaluate the association between daily average temperature and AD outpatient visits from January 1, 2013, to December 31, 2019, in Lanzhou, China. We found that the exposure-response association curve was inversely "s-shaped," low-temperature effects occurred at a lag of 11 days and then lasted for 10 days, and high-temperature effects occurred on the current day and then significantly decreased. Both low and high ambient temperatures can increase the risk of outpatient visits. Compared with median temperature (12.89°C), the cumulative relative risk (RR) of extreme high temperature and moderate-high temperature were 1.847 (95% confidence interval [CI]: 1.613, 2.114) and 1.447 (95% CI: 1.298, 1.614), respectively, at lag0-7 days, and the cumulative RRs of extremely low temperature and moderate-low temperature were 1.004 (95% CI: 0.904, 1.115) and 1.056 (95% CI: 0.925, 1.205), respectively, at lag0-21 days. Females were more sensitive to high temperatures than males, and high or low temperatures had significant effects on children ≤14 years of age. Graphical abstract.