Previous research has found a link between psoriasis and multiple sclerosis (MS). Despite the fact that comparable predisposing genes and pathomechanisms have been proposed, the link between the two remains unknown. In this systematic review and meta-analysis, researchers wanted to look at the relationship between psoriasis and MS. In July 2018, they searched MEDLINE, Embase, and CENTRAL for case-control, cross-sectional, or cohort studies that looked at the chances or risk of psoriasis in people with multiple sclerosis. The Newcastle–Ottawa Scale was used to assess the risk of bias in the included research. The odds ratio (OR) for case-control/cross-sectional studies and the hazard ratio (HR) for cohort studies were calculated using a random-effects model meta-analysis. 

They considered ten publications that presented a total of eleven investigations (5 case-control, four cross-sectional, and two cohort studies). The case-control and cross-sectional studies contained 18,456 MS patients and 8,70,149 controls, respectively, while the two cohort studies had a total of 25,187 MS patients and 2,27,225 controls. Three studies have a high risk of bias in terms of comparability, non-response rate, and control selection. MS was linked to an increased incidence of psoriasis (OR 1.29; 95% [CI] 1.14–1.45) and an increased risk of MS (HR 1.92; 95% CI 1.32–2.80).