Surgical Risks and Costs of Care are Greater in Patients Who Are Super Obese and Undergoing THA

Abstract

Background Patients with morbid obesity, defined as a BMI greater than 40 kg/m 2 , and super obesity, defined as a BMI greater than 50 kg/m 2 , increasingly present for total hip replacement. There is disagreement in the literature whether these individuals have greater surgical risks and costs for the episode of care, and the magnitude of those risks and costs. There also is no established threshold for obesity as defined by BMI in identifying increased complications, risks, and costs of care. Until recently, analysis of higher BMI data was limited to small cohorts from hospital-based data banks, based on BMI or height and weight only, often as part of a multivariate analysis. On October 1, 2010 the Centers for Medicare & Medicaid Services added a fifth digit to the BMI data, V85.xx, in the Medicare data bank, which allowed data mining of cases of patients with higher BMI. To our knowledge, our study is the first large retrospective Medicare data mining study, which allows us to examine BMI levels greater than 40 and 50 kg/m 2 to delineate risks, complications, and costs for these patients. Questions/purposes We sought to quantify (1) the surgical risk, and (2) the costs associated with complications after THA in patients who were morbidly obesity (BMI C 40 kg/m 2 ) or super obese (BMI C 50 kg/m 2 ). Methods This is a retrospective study of patients, using Medicare hospital claims data, who underwent THA. The ICD-9 Clinical Modification (CM) diagnosis code V85.4x was used to identify patients with morbid obesity and with super obesity from October 1, 2010 through December 31, 2014. Patients without any BMI-related diagnosis codes were used as the control group. Twelve complications occurring during the 90 days after THA were analyzed using multivariate Cox models adjusting for patient demographic, comorbidities, and institutional factors. In addition, hospital charges and payments were compared from primary surgery through the subsequent 90 days.Each author certifies that he or she, or a member of his or her immediate family, has no funding or commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research 1 editors and board members are on file with the publication and can be viewed on request. Each author certifies that his or her institution approved or waived approval for the human protocol for this investigation and that all investigations were conducted in conformity with ethical principles of research. This study was performed via electronic collaboration at the authors' institutions. (HR, 3.91; 95% CI, 3.14-4.86; p \ 0.001). In addition, patients with morbid obesity had increased risk of deep vein thrombosis (HR, 1.43; 95% CI, 1.14-1.79; p \ 0.002), pulmonary embolism (HR, 1.57; 95% CI, 1.25-1.99; p \ 0.001), implant failure (HR, 1.48; 95% CI, 1.3-1.68; p \ 0.001), acute ...

The Association of Body Mass Index with Risk of Long-Term Revision and 90-Day Mortality Following Primary Total Hip Replacement

“…Data from the Danish registries demonstrated significantly higher mortality in underweight and normal BMI patients compared to overweight patients and suggested a BMI of 27-28 kg/m 2 was associated with the lowest risk of mortality 22 . In contrast with these findings and our own study, analysis of USA registers and a single center study of 1,744 patients in the UK observed no significant association between BMI and the risk of mortality [17][18][19][20][21] .…”

“…Studies of BMI and mortality at 30-days, 90-days have shown mixed results. Four registry studies in the USA [17][18][19][20] and a single center study in the UK 21 (n=2,000 to 432,841), showed no significant association. Registry studies based in Denmark and the UK (n=34,000 and 410,000) have shown a protective effect of being overweight on 30-and 90-day mortality 4,22 .…”

2018 International Consensus Meeting on Musculoskeletal Infection: Research Priorities from the General Assembly Questions

“…Although there appeared to be strong consensus agreement, the social, political, and economic ramification of establishing an upper limit of the body mass index (BMI) threshold for elective surgery provoked strong arguments between delegates to the point that the question was removed without an official vote. Remarkably, subsequent high‐level peer‐reviewed research was published, which facilitated “unanimous” agreement for the 2018 ICM recommendations based on “Strong” and “Consensus” evidence of the risks (https://www.ors.org/wp-content/uploads/2019/01/BMI-Question.pdf). Other important outcomes of the 2013 ICM were: (i) an evidence‐based definition for hip and knee PJI that has been adopted by the Center for Disease Control (CDC), and (ii) several high‐impact publications as defined by over 1,000 downloads …”

Personalized rehabilitation therapy in obese and elderly patients undergoing hip replacement surgery

“…research conducted among patients with different BMI (Body Mass Index) values underscores that people suffering from morbid obesity (BMI> 50) are exposed to significantly more serious postoperative complications, including the need for early reoperation, which entails higher costs [26]. According to retrospective studies that assess the presence of twelve increasingly serious complications during the first 90 days following surgery, patients with morbid obesity are much more likely to be exposed to implant infections, need for revision, wound dehiscence, deep vein thrombosis, pulmonary embolism, implant failure, acute renal failure, myocardial infarction and implant dislocation [27].…”