Objective To investigate the impact of daily mean temperature on outpatient visits for allergic skin disease (ASD) and to provide a basis for formulating protective strategies for patients and sensitive groups.

Methods Data on ASD visits from the Department of Dermatology at Shanghai Eighth People's Hospital between January 1, 2017 and December 31, 2019 were collected, along with corresponding meteorological and air pollution data. A distributed lag non-linear model (DLNM) was employed to examine the exposure-lag relationship between daily mean temperature and ASD visits. Stratified analyses were performed by disease type, gender, and age group.

Results A total of 33 155 visits for ASD were recorded between 2017 and 2019. Both high and low temperatures were associated with increased ASD outpatient visits (T=-1.0 ℃, RR=2.208, P=0.043; T=29.4 ℃, RR=2.413, P=0.021). Chronic urticaria exhibited a heat effect, with the highest cumulative medical visit risk observed at a 14-day lag (RR=4.252, 95%CI: 2.134‒8.457). Both low and high temperatures increased daily outpatient visits for eczema. No association was found between daily mean temperature and the number of outpatient visits for atopic dermatitis. Subgroup analyses suggested that both high and low temperatures increased the risk of ASD visits among females and individuals aged ≥60 years.

Conclusion Both high and low ambient temperatures are associated with increased outpatient visits for ASD with females and individuals aged ≥60 years showing higher susceptibility.