血清补体3预测2型糖尿病发生：一项巢式病例对照研究

Predictive effects of serum complement factor 3 on type 2 diabetes mellitus：a nested case-control study

目的观察血清补体3（C3）水平升高是否增加2型糖尿病（T2DM）的发生风险。方法本研究为巢式病例对照研究，以重庆某社区非糖尿病人群为研究对象，收集临床资料并追踪随访5年，分别在基线和随访期间行口服75 g葡萄糖耐量试验（OGTT）。按1∶1选取与新诊断T2DM性别、年龄、体质指数（BMI）匹配的糖耐量正常者作为对照组。采用条件Logistic回归分析C3对T2DM发病的影响。结果在5年随访期间，3510名受试者中新诊断T2DM患者255例，男/女例数为141/114，年龄为（61±10）岁，对照组例数、年龄与糖尿病组相同。T2DM组基线血清C3水平较对照组明显升高[（1.29±0.23）比（1.25±0.21）g/L，t=-2.017，P〈0.05]。在校正吸烟、糖尿病家族史、体育锻炼、低密度脂蛋白胆固醇及收缩压等多个因素后，条件Logistic回归分析显示C3水平升高增加T2DM发生风险（OR=1.652，95%CI：1.004〉2.717，P〈0.05），且血清C3水平与T2DM发生风险的关系主要存在于年龄≥55岁、BMI≥24 kg/m^2、总胆固醇≥5.2 mmol/L或甘油三酯〈1.70 mmol/L的人群中（OR=1.138〉2.156，均P〈0.05）。结论血清C3或能预测T2DM的发生。

Objective To investigate whether elevated levels of serum complement factor 3 （C3） increase the risk of developing type 2 diabetes mellitus （T2DM）. Methods This was a nested case-control study. Non-diabetic inhabitants from a community in Chongqing were enrolled and followed up for 5 years. Clinical data were collected. Oral glucose tolerance test （OGTT） was performed at baseline and every 1-2 years. Controls were randomly selected in a 1∶1 ratio to match new T2DM cases according to age, gender, and body mass index（BMI）. Odds ratios （OR） for T2DM were calculated by conditional Logistic regression analysis. Results A total of 255 subjects out of the 3 510 subjects developed T2DM during the 5-year follow-up. There were 141 males and 114 females in the T2DM group, aged （61±10） yrs vs （61±10） yrs in control group. The levels of serum C3 was higher in T2DM group than in control group at baseline （（1.29±0.23） vs （1.25 ± 0.21） g/L, t=-2.017, P〈0.05）. After adjusting for age, gender, BMI, smoking history, family history of diabetes, physical activity, low density lipoprotein cholesterol levels and systolic blood pressure, the risk of developing T2DM was still closely associated with elevated serum C3 levels（OR=1.652, 95%CI：1.004-2.717, P〈0.05）. This correlation occurred mainly in the subjects with age〉55 yrs old, BMI≥24 kg/m^2, total cholesterol≥5.2 mmol/L or triglyceride〈1.70 mmol/L（OR= 1.138-2.156, all P〈0.05）. Conclusion Serum C3 levels may predict the development of T2DM.