Short-term effects of ambient PM 2.5 on respiratory healthcare utilisation in older adults: a time-series study in an industrialising area of Central Thailand

Background: concentrations and respiratory healthcare utilisation among older adults living near a newly established industrial area in central Thailand. Methods: . We used single-lag and moving-average models to assess delayed effects, adjusting for temperature, relative humidity, wind speed, day of the week, and temporal trends. Results: at lag 4 was associated with a 5.5% increase in respiratory healthcare visits (IRR = 1.055, 95% confidence interval = 0.995-1.119), although this association did not reach statistical significance. Subgroup analyses showed numerically larger effect estimates among females and individuals aged 60-69 years; however, interaction tests were not statistically significant. Conclusions: showed a positive but non-significant association with respiratory healthcare utilisation among older adults living near a newly industrialising area. Continued efforts to improve air quality and protect vulnerable populations may help reduce pollution-related respiratory health burdens.