Li Zhaoyi, Zhao Yibin
The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, 31000, People's Republic of China.
Clin Cosmet Investig Dermatol. 2024 Nov 23;17:2659-2667. doi: 10.2147/CCID.S496066. eCollection 2024.
Increasing observational studies are revealing a positive correlation between body mass index (BMI) and the risk of Immune-mediated and Inflammatory Skin Diseases (IMID), however the causal relationship is not yet definite.
The aim of the study was to conduct a two-sample Mendelian randomization (TSMR) to explore the potential causality between BMI, and IMID and biomarkers.
The summary statistics for BMI (n = 322,154), at genome-wide significant level, were derived from the Genetic Investigation of Anthropometric Traits consortium (GIANT). The outcome data for IMID (Psoriasis, vitiligo, Atopic dermatitis (AD), acne, Bullous diseases, Dermatitis herpetiformis, Systemic lupus erythematosus (SLE), Alopecia Areata (AA), Hidradenitis suppurativa (HS) and Systemic sclerosis), and biomarkers were obtained from genome-wide association studies (GWAS). The TSMR analyses were performed in four methods, including inverse variance weighted (IVW) method, MR-Egger regression, the weighted median estimator (WME) and simple mode.
The IVW analysis showed that the per standard deviation (SD) increase in BMI increased a 57% risk of psoriasis. We also observed the suggestive evidence of a causal relationship between BMI and AD and HS. This analysis did not support causality of Vitiligo, Acne, Bullous pemphigoid, Dermatitis herpetiformis, SLE, AA and Systemic sclerosis. The higher risk of BMI may be explained by higher levels of Triglycerides, C-reactive protein (CRP), Interleukin 6, Erythrocyte sedimentation rate (ESR) and Neutrophil count. The high-density lipoprotein (HDL) has an inverse relationship with BMI. No influences were defined for Total cholesterol, low-density lipoprotein (LDL), Rheumatoid factor (RF), Basophil count and Eosinophil count.
Our two-sample MR analysis proved the causal evidence for the associations between BMI and IMID, including psoriasis, AD and HS, which might be related to the elevated expression of biomarkers, including Triglycerides, CRP, Interleukin 6, ESR and neutrophil count.
越来越多的观察性研究揭示了体重指数（BMI）与免疫介导性和炎症性皮肤病（IMID）风险之间存在正相关，但因果关系尚未明确。
本研究旨在进行两样本孟德尔随机化（TSMR），以探讨BMI与IMID及生物标志物之间的潜在因果关系。
在全基因组显著水平上，BMI的汇总统计数据（n = 322,154）来自人体测量性状遗传调查联盟（GIANT）。IMID（银屑病、白癜风、特应性皮炎（AD）、痤疮、大疱性疾病、疱疹样皮炎、系统性红斑狼疮（SLE）、斑秃（AA）、化脓性汗腺炎（HS）和系统性硬化症）的结局数据以及生物标志物数据来自全基因组关联研究（GWAS）。采用四种方法进行TSMR分析，包括逆方差加权（IVW）法、MR-Egger回归、加权中位数估计器（WME）和简单模式。
IVW分析显示，BMI每增加一个标准差（SD），银屑病风险增加57%。我们还观察到BMI与AD和HS之间存在因果关系的提示性证据。该分析不支持白癜风、痤疮、大疱性类天疱疮、疱疹样皮炎、SLE、AA和系统性硬化症的因果关系。BMI较高的风险可能由甘油三酯、C反应蛋白（CRP）、白细胞介素6、红细胞沉降率（ESR）和中性粒细胞计数水平较高来解释。高密度脂蛋白（HDL）与BMI呈负相关。总胆固醇、低密度脂蛋白（LDL）、类风湿因子（RF）、嗜碱性粒细胞计数和嗜酸性粒细胞计数未发现有影响。
我们的两样本MR分析证明了BMI与IMID（包括银屑病、AD和HS）之间关联的因果证据，这可能与甘油三酯、CRP、白细胞介素6、ESR和中性粒细胞计数等生物标志物的表达升高有关。
