Applications of Operations Research and Decision Sciences Techniques on Policies and Issues Related to Obesity and Total Knee Arthroplasty

Abstract

Total Knee Arthroplasty (TKA) is one of the most commonly performed procedures in the United States every year. In 2014 alone, approximately three-quarters of a million were performed at a cost of nearly $40 billion. These figures are only expected to grow. Obesity is one factor influencing this growth. Obese patients are becoming a larger portion of those having TKA procedures and face different risks and benefits when doing so. Some have suggested that TKA be restricted in the obese population to either control spending or because obese patients do not see the same outcomes as nonobese patients. Given the substantial budget impact, it is important to understand the differences faced by obese patients. This dissertation uses meta-analysis, cost-effectiveness analysis, and agent-based modeling to inform decision making about obese patients and TKA. The meta-analysis resolves some uncertainty in the current literature around complication and implant survival rates in individuals with different obesity classifications. Then, the cost-effectiveness analysis explores the relative costs and benefits of the TKA procedure by obesity class. Finally, a trend model is built in an agent-based framework to examine the volume of TKA procedures and the budget impact for the entire US population under different potential future scenarios. These results show that even though obese patients do face higher rates of complications than their nonobese counterparts, this alone does not rule out TKA as a reasonable option for those patients. Even in the heaviest patients, TKA is cost-effective. The budget impact for restricting access to obese patients is minimal due to the offsetting rise in costs of living with osteoarthritis without surgical intervention. There are potential policy solutions to the large expenditure on TKA and certain areas need further investigation before guidelines should be changed. Obesity does matter when considering TKA policies and outcomes, but outright bans on TKA in obese patients may not be the best policy solutions.