Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC, USA.
Canadian VIGOUR Centre, University of Alberta, Edmonton, Canada.
Am Heart J. 2020 Jan;219:47-57. doi: 10.1016/j.ahj.2019.09.016. Epub 2019 Oct 20.
Obesity is a risk factor for type 2 diabetes (T2D) and cardiovascular disease (CVD). Whether obesity affects outcomes among those with T2D and atherosclerotic CVD (ASCVD) remains uncertain. Our objective was to investigate the relationship between body mass index (BMI) and ASCVD outcomes among TECOS participants with T2D and ASCVD.
BMI categories were defined as underweight/normal weight (BMI <25 kg/m), overweight (25-29.9 kg/m), obese class I (30-34.9 kg/m), obese class II (35-39.9 kg/m), and obese class III (≥ 40 kg/m). Asian-specific BMI categories were applied to Asian participants. Kaplan-Meier survival analysis and Cox proportional hazards models were used to examine associations between baseline BMI and a composite CV outcome (CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for unstable angina).
For 14,534 TECOS patients with available BMI, mean age was 65.5 years; 29.3% were female, 32.0% non-White, and 23.1% insulin-treated, with median 3 years' follow-up. At baseline, 11.6% (n = 1686) were underweight/normal weight, 38.1% (n = 5532) overweight, 32.2% (n = 4683) obese class I, 12.4% (n = 1806) obese class II, and 5.7% (n = 827) obese class III. The composite CV outcome occurred in 11.4% (n = 1663) of participants; the outcome risk was lower, compared with under/normal weight, in overweight (HR 0.83, 95% CI 0.71-0.98) and obese class I (HR 0.79, 95% CI 0.67-0.93) individuals. Obesity was not associated with worse glycemic control.
The majority of TECOS participants with ASCVD and T2D were overweight or obese, yet overweight or obese class I individuals had lower CV risk than those who were under/normal weight. These results suggest the presence of an obesity paradox, but this paradox may reflect an epidemiological artifact rather than a true negative association between normal weight and clinical outcomes.
肥胖是 2 型糖尿病（T2D）和心血管疾病（CVD）的危险因素。肥胖是否会影响患有 T2D 和动脉粥样硬化性 CVD（ASCVD）的患者的结局仍不确定。我们的目的是研究 TECOS 参与者中 BMI 与 ASCVD 结局之间的关系，这些参与者患有 T2D 和 ASCVD。
BMI 类别定义为体重不足/正常体重（BMI<25kg/m）、超重（25-29.9kg/m）、肥胖 I 级（30-34.9kg/m）、肥胖 II 级（35-39.9kg/m）和肥胖 III 级（≥40kg/m）。亚洲参与者采用亚洲特定的 BMI 类别。使用 Kaplan-Meier 生存分析和 Cox 比例风险模型来检查基线 BMI 与复合 CV 结局（CV 死亡、非致死性心肌梗死、非致死性卒中和不稳定型心绞痛住院）之间的关联。
在 14534 名可提供 BMI 的 TECOS 患者中，平均年龄为 65.5 岁；29.3%为女性，32.0%为非白人，23.1%接受胰岛素治疗，中位随访 3 年。基线时，11.6%（n=1686）为体重不足/正常体重，38.1%（n=5532）为超重，32.2%（n=4683）为肥胖 I 级，12.4%（n=1806）为肥胖 II 级，5.7%（n=827）为肥胖 III 级。复合 CV 结局发生在 11.4%（n=1663）的参与者中；与体重不足/正常体重相比，超重（HR0.83，95%CI0.71-0.98）和肥胖 I 级（HR0.79，95%CI0.67-0.93）个体的结局风险较低。肥胖与血糖控制不佳无关。
大多数患有 ASCVD 和 T2D 的 TECOS 参与者超重或肥胖，但超重或肥胖 I 级个体的 CV 风险低于体重不足/正常体重者。这些结果表明存在肥胖悖论，但这种悖论可能反映了一种流行病学假象，而不是正常体重与临床结局之间的真实负相关。
