Effect of PM2.5 exposure on the risk of incident autoimmune diseases: a prospective cohort study in Taiwan

BACKGROUND: The interaction between fine particulate matter (PM2.5) and genetic factors is thought to play a significant role in the development of autoimmune diseases. However, the impact of PM2.5 exposure on the onset of these diseases remains unclear. This population-based cohort study investigated the effect of year-to-year variations in PM2.5 exposure levels on incident autoimmune disease risk in Taiwanese adults. METHODS: In this longitudinal study, we followed-up 276,254 adults from the Taiwan MJ cohort (2005-2017) for 9.3 years to identify incident autoimmune diseases cases, ascertained from the patients' clinical and laboratory reports. Autoimmune diseases were categorized as systemic and organ-specific. Data on residential address-specific annual PM2.5 concentrations were obtained from Taiwan Air Quality-Monitoring sites. A time-dependent Cox regression model, considering death as a competing risk, was used to assess the effect of year-to-year variations in PM2.5 exposure levels on autoimmune disease risk. RESULTS: increase) had a significantly increased risk of incident autoimmune diseases (adjusted hazard ratio [aHR], 2.97; 95% confidence interval [CI], 2.84-3.11), particularly systemic lupus erythematosus (SLE) (aHR, 3.28; 95% CI, 2.99-3.59) and Sjögren's syndrome (aHR, 2.82; 95% CI, 2.66-2.98). CONCLUSIONS: Proactive air pollution control strategies are crucial for the prevention of autoimmune diseases, particularly SLE and Sjögren's syndrome.