Evaluation of disparities in multiple sclerosis risk by age, sex, and nativity in Kuwait:1980-2019

Abstract Objective: This cross-sectional cohort study quantified the disparities in MS risk by age, sex, nativity from1980 to 2019. Methods: Age-standardized MS incidence rate (ASIR) (per 100,000 person-years) overall and by subcohorts defined by cross-classification of the period (5-year groups) of diagnosis, age at onset, sex (female or male) and nativity (Kuwaiti or non-Kuwaiti) were computed and analyzed using multivariable negative binomial model. Results: Overall MS ASIR (per 100,000 person-years) was 3.41 (95% CI: 1.61, 5.21), which increased exponentially from1980 to 2014 before drifting downward in 2015-2019 period. Compared with adults (age ≥ 40 years), men, non-Kuwaiti residents respectively, young adults (20-39 years), females and Kuwaiti nationals were significantly (p Conclusions: A high overall MS ASIR (per 100,000 person-years) was recorded with substantial temporal variation between 1980 and 2019. Young adults (20-39 years), females and Kuwaiti nationals constituted MS high-risk groups. The knowledge of underlying interface pathways between genetic and environmental factors may provide insights into MS pathogenesis and leads for future research.