Global burden and trends of rheumatoid arthritis attributable to smoking from 1990 to 2021 with forecasts to 2050

BACKGROUND: Smoking is a key modifiable risk factor for rheumatoid arthritis (RA). This study aimed to assess the global burden of RA attributable to smoking and analyze its spatiotemporal trends from 1990 to 2021, with forecasts to 2050. METHODS: Using data from the Global Burden of Disease Study 2021, we extracted deaths, disability-adjusted life years (DALYs), and age-standardized rates (ASRs) for RA attributable to smoking across 204 countries and regions. Analyses were stratified by age, sex, socio-demographic index (SDI), and region. Temporal trends were assessed using estimated annual percentage change (EAPC), and future burden was projected using ARIMA models. RESULTS: From 1990 to 2021, global deaths and DALYs due to RA attributable to smoking increased by 26.3% and 48.1%, respectively, reaching 2,264 deaths (95% UI: 1509-2911) and 215,780 DALYs (95% UI: 147,153-300,761) in 2021. However, the corresponding ASRs declined, with ASDR falling from 0.05 to 0.03 per 100,000 and ASRDALYs from 3.44 to 2.48 per 100,000. The burden was higher among males, the elderly, and middle-to-high SDI regions. Males had 2.42 times more deaths and 1.68 times more DALYs than females. Forecasts indicate continued increases in absolute deaths and DALYs through 2050, despite declining ASRs. CONCLUSION: The global burden of RA attributable to smoking remains substantial and is projected to grow. Targeted tobacco control and public health strategies are urgently needed to mitigate this preventable cause of RA.