Genetic insights into the risk of metabolic syndrome and its components on psoriasis: A bidirectional Mendelian randomization.

The role of metabolic syndrome (MetS) on psoriasis has been explored only in observational studies. We conducted this bidirectional Mendelian randomization (MR) to clarify the causal relationship between MetS and its components and psoriasis. The genetic instruments of MetS and its five components (waist circumference [WC], hypertension, fasting blood glucose [FBG], triglycerides [TG], and high-density lipoprotein cholesterol [HDL-C]) were obtained from public genome-wide association studies (GWAS). Outcome datasets for psoriasis were collected from the FinnGen Biobank Analysis Consortium. The main method was inverse variance weighting, complemented by sensitivity approaches to rectify potential pleiotropy. MetS, WC, and hypertension increase the risk of psoriasis (MetS, odd ratios [OR] = 1.17, 95% confidence interval [CI] 1.08-1.27, p = 1.23e-04; WC, OR = 1.65, 95% CI  1.42-1.93, p = 1.06e-10; hypertension, OR = 2.02, 95% CI 1.33-3.07, p = 0.0009). In the reverse analysis, no causal association between psoriasis and MetS and its five components was identified. We provide novel genetic evidence that MetS, WC, and hypertension are risk factors for the development of psoriasis. Early management of MetS and its components may be an effective strategy to decrease the risk of psoriasis.