Departments of Health Sciences Research (H.M.K., S.L.V., W.K.K., and J.M.N.) and Orthopedic Surgery (D.G.L.), College of Medicine, Mayo Clinic, 200 First Street S.W., Rochester, MN 55905. E-mail address for H.M. Kremers:
J Bone Joint Surg Am. 2014 May 7;96(9):718-24. doi: 10.2106/JBJS.M.00819.
Obesity prevalence continues to rise in the United States. We sought to examine the effect of obesity on length of hospital stay and direct medical costs in a large cohort of patients who underwent total knee arthroplasty.
The study included 8129 patients who had undergone 6475 primary total knee arthroplasties and 1654 revision total knee arthroplasties at a large U.S. medical center from January 1, 2000, to September 30, 2008. Patients with bilateral procedures within ninety days following the index admission were excluded. Data on clinical and surgical characteristics and complications were obtained from the original medical records and the institutional joint registry. Patients were classified into eight groups based on their body mass index at the time of surgery. Direct medical costs were calculated in 2010 U.S. dollars by using standardized, inflation-adjusted costs for services and procedures billed during hospitalization and the ninety-day window. Study end points were hospital length of stay and direct medical costs. End points were compared across the eight body mass index categories in both unadjusted and multivariable risk-adjusted analyses. Linear regression models were used to determine the cost impact associated with increasing body mass index and obesity accounting for comorbidities and complications.
Body mass index data were available for 99.5% of patients and ranged from 15 to 73 kg/m2. Length of stay and the direct medical costs were lowest for patients with body mass index values in the normal to overweight range. Increasing body mass index was associated with significantly longer hospital stays and costs. Every 5-unit increase in body mass index beyond 30 kg/m2 was associated with approximately $250 to $300 higher hospitalization costs in primary total knee arthroplasty and $600 to $650 higher hospitalization costs in revision total knee arthroplasty. These estimates persisted after adjusting for comorbidities or complications.
Obesity is associated with longer hospital stays and higher costs in total knee arthroplasty. The effect of obesity on costs appears to be independent of obesity-related comorbid conditions and complications.
肥胖在美国的患病率持续上升。我们试图在一个接受全膝关节置换术的大型患者队列中研究肥胖对住院时间和直接医疗费用的影响。
这项研究纳入了 2000 年 1 月 1 日至 2008 年 9 月 30 日期间，在美国一家大型医疗中心接受了 6475 例初次全膝关节置换术和 1654 例翻修全膝关节置换术的 8129 名患者。排除了在索引住院后 90 天内进行双侧手术的患者。从原始病历和机构关节登记处获得了临床和手术特征以及并发症的数据。根据手术时的体重指数，患者被分为 8 组。通过使用住院期间和 90 天窗口内计费的服务和程序的标准化、通胀调整后的成本，计算 2010 年的直接医疗费用。研究终点是住院时间和直接医疗费用。在未调整和多变量风险调整分析中，比较了 8 个体重指数组之间的终点。线性回归模型用于确定与体重指数增加和肥胖相关的成本影响，同时考虑了合并症和并发症。
体重指数数据可用于 99.5%的患者，范围为 15 至 73 kg/m2。体重指数值在正常到超重范围内的患者的住院时间和直接医疗费用最低。体重指数增加与住院时间和费用显著延长相关。初次全膝关节置换术时，体重指数每增加 5 个单位，住院费用增加约 250 至 300 美元；翻修全膝关节置换术时，住院费用增加约 600 至 650 美元。这些估计在调整了合并症或并发症后仍然存在。
肥胖与全膝关节置换术的住院时间延长和费用增加有关。肥胖对成本的影响似乎独立于肥胖相关的合并症和并发症。
