Identifying Risk Factors for the Rising Prevalence of Multiple Sclerosis in Saudi Arabia: A case-control analysis

Objective: This study aims to identify risk factors linked to the increasing prevalence of multiple sclerosis (MS) in Saudi Arabia. Multiple sclerosis is a chronic autoimmune condition affecting the central nervous system, marked by inflammation and damage to nerves and the myelin sheath. Method: A case-control study conducted from September 2022 to January 2024 included 832 participants—263 diagnosed with MS and 569 controls. Controls were matched by age, gender, residence, and employment status. Data was collected using a validated questionnaire, with written consent obtained from participants aged 18 and older. Logistic regression analysis was used to ascertain risk factors. Results: Out of 832 participants, 263 (31.6%) were diagnosed with MS. The greatest percentage of MS cases occurred in the 25–34 age range (37.7%). After adjusting for potential confounders, smoking was significantly associated with increased MS risk (AOR = 2.34, 95% CI: [1.22–4.48], p = 0.01), as were vitamin D deficiency (AOR = 1.97, 95% CI: [1.31–2.98], pp = 0.02). Conversely, vitamin D supplementation was associated with a substantial reduction in MS risk (AOR = 0.17, 95% CI: [0.10–0.28], p < 0.001), as was coffee consumption (AOR = 0.53, 95% CI: [0.30–0.96], p < 0.04). Conclusion: Smoking, vitamin D deficiency, and a history of childhood sexual abuse increase MS risk, while vitamin D supplementation and coffee consumption reduce it. Further research is essential to confirm these findings.