Global, regional and national burden of rheumatoid arthritis, and attributable risk factors from 1990 to 2019: update from the Global Burden of Disease 2019 study

Objective Statistical data on the incidence, disability-adjusted life years (DALYs) and burden of rheumatoid arthritis (RA), and associated risk factors are essential for the development of effective treatment options. The Global Burden of Disease (GBD) study provides a unique opportunity to evaluate the aforementioned parameters. Methods The RA incidence rate, age-standardised incidence rate (ASR), DALYs and estimated annual percentage change (EAPC) between 1990 and 2019 were evaluated, using data from 204 territories and countries from the GBD 2019. Risk factors associated with DALYs in patients with RA were estimated using the comparative risk assessment framework of the GBD study. Results The results of the present study demonstrated that the incidence of RA increased from 567,462.89 to 1,074,390.80 cases, with an ASR of 13/ 100,000 patients between 1990 and 2019. The number of RA cases and DALYs were increased in all socio-demographic index quintiles during the study period. A significant negative association was found between EAPCs and age-standardised DALYs per 100,000 (rho= -0.60; p<0.001). Notably, females exhibited an increased ASRs and DALYs than males, at both global and regional levels during the study period. Globally, age-standardised DALYs increased in an age-dependent manner, with the highest rate in the 60-69 years age group. Moreover, smoking was the predominant contributor to RA-associated DALYs for males worldwide, and this trend decreased from 1990 to 2019. Conclusion The incidence rate of RA and associated DALYs are increasing worldwide, particularly among female patients. This trend is expected to increase, due an ageing population. Notably, smoking remained the predominant risk factor for RA-associated DALYs in males. Therefore, further investigations into the impact of smoking, and improvements in early diagnosis and treatment strategies for RA are required to reduce the global burden of RA.