Supplementary Material for: Association between Inflammatory and Obesity Markers in a Swiss Population-Based Sample (CoLaus Study)

<b><i>Objective:</i></b> To assess the associations between obesity markers (BMI, waist circumference and %body fat) and inflammatory markers (interleukin-1β (IL-1β); interleukin-6 (IL-6); tumor necrosis factor-α (TNF-α) and high-sensitivity C-reactive protein (hs-CRP)). <b><i>Methods:</i></b> Population sample of 2,884 men and 3,201 women aged 35–75 years. Associations were assessed using ridge regression adjusting for age, leisure-time physical activity, and smoking. <b><i>Results:</i></b> No differences were found in IL-1β levels between participants with increased obesity markers and healthy counterparts; multivariate regression showed %body fat to be negatively associated with IL-1β. Participants with high %body fat or abdominal obesity had higher IL-6 levels, but no independent association between IL-6 levels and obesity markers was found on multivariate regression. Participants with abdominal obesity had higher TNF-α levels, and positive associations were found between TNF-α levels and waist circumference in men and between TNF-α levels and BMI in women. Obese participants had higher hs-CRP levels, and these differences persisted after multivariate adjustment; similarly, positive associations were found between hs-CRP levels and all obesity markers studied. <b><i>Conclusion:</i></b> Obesity markers are differentially associated with cytokine levels. %Body fat is negatively associated with IL-1β; BMI (in women) and waist circumference (in men) are associated with TNF-α; all obesity markers are positively associated with hs-CRP.

**研究目的**：评估肥胖指标（obesity markers）与炎症指标（inflammatory markers）之间的关联，其中肥胖指标涵盖身体质量指数（BMI）、腰围（waist circumference）及体脂百分比（%body fat），炎症指标包括白细胞介素-1β（IL-1β）、白细胞介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）及高敏C反应蛋白（hs-CRP）。
**研究方法**：纳入年龄35~75岁的2884名男性与3201名女性作为人群样本。采用岭回归（ridge regression）分析二者关联，并校正年龄、闲暇时间体力活动及吸烟情况。
**研究结果**：肥胖指标异常的参与者与健康对照者的IL-1β水平无显著差异；多变量回归（multivariate regression）分析显示，体脂百分比与IL-1β呈负相关。高体脂百分比或腹型肥胖（abdominal obesity）的参与者IL-6水平更高，但多变量回归分析未发现IL-6水平与肥胖指标存在独立相关性。腹型肥胖参与者的TNF-α水平更高，且男性中TNF-α水平与腰围呈正相关，女性中TNF-α水平与BMI呈正相关。肥胖参与者的hs-CRP水平更高，经多变量校正后该差异依然存在；同样，hs-CRP水平与本次研究纳入的所有肥胖指标均呈正相关。
**研究结论**：不同肥胖指标与细胞因子（cytokine）水平的关联存在差异。体脂百分比与IL-1β呈负相关；女性的BMI与男性的腰围分别与TNF-α相关；所有肥胖指标均与hs-CRP呈正相关。