Al Yafi Motaz, Nasif Abdullah, Glosser Logan D, Ren Gang, Ahemd Ayman, Nazzal Munier, Osman Mohamed
Department of Surgery, University of Toledo, Toledo, OH, USA.
University of Toledo College of Medicine and Life Sciences, Toledo, OH, USA.
Vascular. 2023 Oct;31(5):922-930. doi: 10.1177/17085381221087824. Epub 2022 Apr 22.
Non-traumatic lower extremity amputation (LEA) is associated with significant morbidity and mortality. Diabetes mellitus (DM) and peripheral vascular disease (PVD) are associated with increased risk for LEA. As such, DM and PVD account for 54% of all LEA's, performed in the United States annually. As obesity is highly associated with both DM and PVD, our study sought to explore the relationship between LEA and obesity defined by BMI.
Using the National Inpatient Sample (NIS) database, a retrospective review of patients who underwent non-traumatic LEA (LEA) between 2008 and 2014 was performed. The International Classification of Diseases 9th edition (ICD-9) codes were utilized to determine the diagnoses, comorbidities, and procedures. Patient BMIs were classified as follows: Non-obese [BMI <30], Obesity class I [BMI 30-34.9], Obesity class II [BMI 35-39.9], and Obesity class III [BMI ≥40]. Predictors for LEA were compared between groups using chi-square test and binary logistic regression to identify possible underlying factors associated with LEA. We also conducted a multivariate analysis to measure the effect of multiple variables on LEA.
We identified 16,259 patients with non-traumatic LEA and a mean age of 59.9 years. Rate of amputation in females was lower than males at 0.35% vs 0.87% respectively ( < 0.001). Of patients that underwent amputation there was a V-shape trend based on BMI, with 30.4% in non-obese patients, 18.2% in obesity class I, 17.3% in obesity class II, and 34.1% in obesity class III. The incidence of diabetes increased with obesity class, while the incidence of PVD decreased. Interestingly, of those with DM there was an inverse relationship between amputation rate and BMI class, with LEA rates in non-obese versus obesity class III patients were 1.63% vs 0.98% respectively ( < 0.001). Similarly, patients who had both diabetes and PVD showed a downward trend in LEA rate as obesity class increased; non-obese patients had a LEA rate of 8.01%, while obesity class III had 4.65% ( < 0.001). Patients in higher income bracket have lower odds of LEA (OR 0.77, < 0.001) compared to the lowest income patients. Also, patients with comorbidities such as PVD (OR 10.78), diabetes (OR 5.02), renal failure (OR 1.41), and hypertension (OR 1.36) had higher odds to get an LEA ( < 0.001). Individuals with obesity class III are almost at half the odds (OR 0.52) to get an LEA compared to non-obese ( < 0.001).
Higher BMI and female gender are protective factors against lower extremity amputation. Factors that predisposing to LEA include lower household income and certain comorbidities such as PVD, diabetes, renal failure, and hypertension. These findings warrant further research to identify patients at high risk for LEA and help develop management guidelines for targeted populations.
非创伤性下肢截肢（LEA）与显著的发病率和死亡率相关。糖尿病（DM）和外周血管疾病（PVD）会增加LEA的风险。因此，在美国每年进行的所有LEA手术中，DM和PVD占54%。由于肥胖与DM和PVD都高度相关，我们的研究旨在探讨LEA与由体重指数（BMI）定义的肥胖之间的关系。
利用国家住院样本（NIS）数据库，对2008年至2014年间接受非创伤性LEA的患者进行回顾性研究。使用国际疾病分类第九版（ICD - 9）编码来确定诊断、合并症和手术。患者的BMI分类如下：非肥胖[BMI <30]、I类肥胖[BMI 30 - 34.9]、II类肥胖[BMI 35 - 39.9]和III类肥胖[BMI≥40]。使用卡方检验和二元逻辑回归比较各组之间LEA的预测因素，以确定与LEA相关的潜在因素。我们还进行了多变量分析，以测量多个变量对LEA的影响。
我们确定了16259例非创伤性LEA患者，平均年龄为59.9岁。女性的截肢率低于男性，分别为0.35%和0.87%（<0.001）。在接受截肢的患者中，基于BMI呈V形趋势，非肥胖患者中占30.4%，I类肥胖患者中占18.2%，II类肥胖患者中占17.3%，III类肥胖患者中占34.1%。糖尿病的发病率随肥胖等级增加，而PVD的发病率下降。有趣的是，在患有DM的患者中，截肢率与BMI等级呈负相关，非肥胖患者与III类肥胖患者的LEA率分别为1.63%和0.98%（<0.001）。同样，同时患有糖尿病和PVD的患者，随着肥胖等级增加，LEA率呈下降趋势；非肥胖患者的LEA率为8.01%，而III类肥胖患者为4.65%（<0.001）。与收入最低的患者相比，高收入阶层的患者发生LEA的几率较低（OR 0.77，<0.001）。此外，患有PVD（OR 10.78）、糖尿病（OR 5.02）、肾衰竭（OR 1.41）和高血压（OR 1.36）等合并症的患者发生LEA的几率更高（<0.001）。与非肥胖患者相比，III类肥胖个体发生LEA的几率几乎减半（OR 0.52）（<0.001）。
较高的BMI和女性性别是下肢截肢的保护因素。导致LEA的因素包括家庭收入较低以及某些合并症，如PVD、糖尿病、肾衰竭和高血压。这些发现值得进一步研究，以确定LEA的高危患者，并帮助制定针对目标人群的管理指南。
