Abstract: Background　Diabetic foot（DF） is associated with a high mortality rate mainly due to DF-related cardiovascular and cerebrovascular accidents. There are few studies on risk predictors of cardiovascular and cerebrovascular events and risk stratification of cardiovascular events in DF patients. Therefore，it is of great significance to screen out a promising indicator to accurately predict the risk of cardiovascular and cerebrovascular events in DF patients. Objective　The study aimed to evaluate the value of toe-brachial index（TBI） as a predictor of cardiovascular and cerebrovascular events in DF patients.Methods　A retrospective study was carried out on 197 DF patients with hospitalized treatment selected from Department of Endocrinology，Air Force Medical Center，PLA from February 2014 to September 2016. They were divided into three groups according to the TBI value：normal TBI（N-TBI group，TBI≥0.7，n=107），low TBI（L-TBI group，0.5≤TBI<0.7，n=41） and extremely low TBI（EL-TBI group，TBI<0.5，n=49）. Clinical data，including gender，age，body mass index（BMI），duration of diabetes，history of hypertension，hyperlipidemia，chronic renal insufficiency and smoking，levels of HbA1c，serum creatinine，and blood lipid indicators，and use of aspirin and statin were collected. All of them were followed up for 36 months. Multivariate Logistic regression analysis，Kaplan-Meier survival analysis and Cox regression models were used to evaluate the value of TBI in predicting the risk of cardiovascular and cerebrovascular events. Results　The mean follow-up time for the participants was（33.5±7.9） months，during which 27（13.7%） developed cardiovascular and cerebrovascular events，and 10（5.1%）died. Multivariate Logistic regression analysis showed that TBI<0.7 was associated with increased risk of cardiovascular and cerebrovascular events in DF patients〔OR（95%CI）=11.034（3.486，34.922）〕. The survival time revealed by Kaplan-Meier analysis was 35.24，32.81，and 30.56 months for N-TBI，L-TBI and EL-TBI groups，respectively，with significantly different risks for cardiovascular and death events（P<0.05）. Cox regression analysis showed that after adjusting for age，the HR value of cardiovascular and cerebrovascular events in L-TBI and EL-TBI groups increased by a factor of 4.749〔95%CI（1.199，18.804）〕，and 10.495〔95%CI（3.210，34.313）〕，respectively，compared with that of N-TBI group. Conclusion　TBI can be used as an independent predictor of cardiovascular and cerebrovascular events in patients with DF，and the risk of cardiovascular and cerebrovascular accidents increases significantly with the decrease of TBI.

Key words: Diabetic foot, Toe-brachial index, Cardiovascular and cerebrovascular events, Forecasting

摘要： 背景　糖尿病足（DF）具有较高的死亡率，心脑血管意外是主要死亡原因。目前，缺乏对DF患者发生心脑血管事件风险预测指标及心血管事件风险分层的研究。因此，筛选出一个精确地预测DF患者发生心脑血管事件风险的指标意义重大。目的　探讨趾臂指数（TBI）对DF患者心脑血管事件发生风险的预测价值。方法　采用回顾性研究，纳入2014年2月—2016年9月于空军特色医学中心内分泌科住院治疗且无心脑血管疾病的DF患者197例。根据TBI，分为N-TBI组（TBI≥0.7，n=107）、L-TBI组（0.5≤TBI<0.7，n=41）、EL-TBI组（TBI<0.5，n=49）。收集患者的临床资料，包括性别、年龄、吸烟史、体质指数（BMI）、糖尿病（DM）病程、既往史（高血压、高脂血症、慢性肾功能不全）、糖化血红蛋白（HbA1c）、肌酐、血脂指标、药物应用情况，随访36个月。采用多因素Logistic回归分析、Kaplan-Meier生存曲线及Cox比例风险模型评估TBI对DF患者发生心脑血管事件的预测价值。结果　197例患者平均随访时间为（33.5±7.9）个月，心脑血管事件发生率为13.7%（27/197），死亡率为5.1%（10/197）。多因素Logistic回归分析结果显示，TBI<0.7〔OR（95%CI）=11.034（3.486，34.922）〕是DF患者发生心脑血管事件的危险因素。Kaplan-Meier生存曲线显示，N-TBI组、L-TBI组、EL-TBI组生存时间分别为35.24、32.81、30.56个月，三组发生心血管事件和死亡事件的风险有统计学差异（P<0.05）。Cox比例风险模型分析结果显示，校正年龄因素后，与N-TBI组比较，L-TBI组发生心脑血管事件的HR（95%CI）为4.749（1.199，18.804），EL-TBI组发生心脑血管事件的HR（95%CI）为10.495（3.210，34.313）。结论　TBI可作为预测DF患者发生心脑血管事件的独立预测指标，且随着TBI的降低心脑血管意外发生风险增高。

关键词: 糖尿病足, 趾臂指数, 心脑血管事件, 预测