Evidence of a Causal Relationship Between Body Mass Index and Immune-Mediated and Inflammatory Skin Diseases and Biomarkers: A Mendelian Randomization Study

The study used a two-sample Mendelian randomization approach with data from 322,154 individuals to explore the causal relationship between BMI and immune-mediated and inflammatory skin diseases (IMID). It found a 57% increased risk of psoriasis per standard deviation increase in BMI and suggestive evidence of a causal link between BMI and atopic dermatitis (AD) and hidradenitis suppurativa (HS). No causal links were found for other conditions like vitiligo, acne, and alopecia areata. The study suggests that elevated BMI may increase the risk of certain IMIDs through higher levels of biomarkers such as triglycerides, C-reactive protein, interleukin 6, erythrocyte sedimentation rate, and neutrophil count, while high-density lipoprotein showed an inverse relationship with BMI. Managing obesity could potentially improve outcomes for patients with these skin conditions.