Xu Jie, Wang Anxin, Meng Xia, Jing Jing, Wang Yilong, Wang Yongjun
From the Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, China (J.X., A.W., X.M., J.J., Yilong Wang, Yongjun Wang).
China National Clinical Research Center for Neurological Diseases, Beijing (J.X., A.W., X.M., J.J., Yilong Wang, Yongjun Wang).
Stroke. 2019 Jun;50(6):1423-1429. doi: 10.1161/STROKEAHA.118.023817. Epub 2019 May 2.
Background and Purpose- The underlying mechanisms of stroke-obesity paradox are still not fully understood. This study aims to investigate the contribution of insulin resistance to the association between body mass index and stroke outcomes. Methods- Patients with ischemic stroke without history of diabetes mellitus in the Abnormal Glucose Regulation in Patients With Acute Stroke Across-China registry were included. Overweight or obese was defined as body mass index ≥23, and the median of homeostasis model assessment-insulin resistance index was chosen as cutoff to define insulin resistance. Cox or logistic regression model was used to assess the interaction between body mass index and homeostasis model assessment-insulin resistance on 1-year prognosis (all-cause mortality and poor functional outcome defined as modified Rankin Scale score 3-6). Results- Of 1227 study participants, the median homeostasis model assessment-insulin resistance was 1.9 (interquartile range, 1.1-3.1) and 863 (70.3%) patients were classified as overweight or obese. Among insulin-resistant patients, overweight/obese patients experienced one-half of the risk of death after stroke than their low/normal weight counterparts (9.42% versus 17.69%, unadjusted hazard ratio, 0.50; 95% CI, 0.31-0.82), while among insulin-sensitive ones, no significant difference of mortality risk was found (7.58% versus 6.91%, 1.07; 0.57-1.99). Similar trends were observed for poor functional outcome. Results were similar after adjustments for confounders. There were significant interactions between body mass index and homeostasis model assessment-insulin resistance on the risks of mortality (=0.045) and poor functional outcome (=0.049). Conclusions- We observed the obesity paradox for mortality and functional outcome in insulin-resistant patients but did not find the obesity paradox in insulin-sensitive patients. Insulin resistance may be one of the mechanisms underlying the obesity paradox of the outcome in patients with ischemic stroke.
背景与目的——卒中-肥胖悖论的潜在机制仍未完全明确。本研究旨在探究胰岛素抵抗在体重指数与卒中预后关联中的作用。方法——纳入中国急性卒中患者血糖调节异常登记研究中无糖尿病病史的缺血性卒中患者。超重或肥胖定义为体重指数≥23，选取稳态模型评估-胰岛素抵抗指数的中位数作为界定胰岛素抵抗的切点。采用Cox或逻辑回归模型评估体重指数与稳态模型评估-胰岛素抵抗对1年预后（全因死亡率和不良功能转归，定义为改良Rankin量表评分3 - 6分）的交互作用。结果——1227例研究参与者中，稳态模型评估-胰岛素抵抗的中位数为1.9（四分位数间距，1.1 - 3.1），863例（70.3%）患者被分类为超重或肥胖。在胰岛素抵抗患者中，超重/肥胖患者卒中后死亡风险是体重正常/偏低患者的一半（9.42% 对17.69%，未校正风险比，0.50；95%CI，0.31 - 0.82），而在胰岛素敏感患者中，未发现死亡风险有显著差异（7.58% 对6.91%，1.07；0.57 - 1.99）。不良功能转归也观察到类似趋势。校正混杂因素后结果相似。体重指数与稳态模型评估-胰岛素抵抗在死亡风险（P = 0.045）和不良功能转归风险（P = 0.049）上存在显著交互作用。结论——我们在胰岛素抵抗患者中观察到了肥胖悖论与死亡率及功能转归相关，但在胰岛素敏感患者中未发现肥胖悖论。胰岛素抵抗可能是缺血性卒中患者结局肥胖悖论的潜在机制之一。
