Impact of diurnal temperature range on rhinitis in Lanzhou, China: Accounting for COVID-19 effects

Rhinitis is a global public health issue. A distributed lag non-linear model (DLNM) was used to examine the impact of diurnal temperature range (DTR) on nonallergic rhinitis (NAR) and allergic rhinitis (AR) in Lanzhou, China. Stratified analyses by age, gender, seasons, and the COVID-19 period were conducted, alongside extreme-DTR and attributable risk analyses. Using 37,225 cases, we found: The nonlinear DTR-rhinitis relationship: high- and low-DTR acutely impacted AR, while primarily high DTR moderately affected NAR during full and pre-COVID-19 periods. COVID-19 transformed the adverse impact of low-DTR into protective effects. In full study period, AR showed age heterogeneity, and NAR displayed age and gender differences. In pre-COVID-19 study period, AR had age and gender variations. The age < 18 group, vulnerable to NAR and AR, requires concerns. Low-DTR exhibits protective effects during cold seasons, while it poses adverse effects and increased risks in warm seasons. Moderate high DTR contributed most to rhinitis outpatients. In conclusion, NAR and AR demonstrate distinct responses to short-term DTR exposure, which may be influenced by COVID-19 and seasonal factors. Future research is essential to assess the long-term impacts of DTR and COVID-19 effects on NAR and AR.