Should Medicare expand bariatric surgery to obese beneficiaries without pre-existing comorbidities?

Background/Introduction: The 2006 Medicare bariatric surgery National Coverage Determination (NCD) does not cover obese beneficiaries who do not have a CMS-defined comorbidity, such as diabetes and/or hypertension. We investigated whether sufficient evidence exists for Medicare to consider an expansion of the bariatric surgery NCD to prediabetic obese beneficiaries. Specifically, this research 1) investigated and compared the outcomes of bariatric surgery on prediabetic obese individuals (who did not have other major comorbidities) to surgery patients with diabetes and/or hypertension, 2) estimated the increase in the eligible Medicare population if the bariatric surgery NCD was broadened to include obese prediabetics, and 3) estimated the cost implications of a Medicare policy change to cover bariatric surgery for obese prediabetic patients.

Design: The study design was a cross-sectional analysis that relied primarily on two secondary data sources: 1) Nationwide Inpatient Sample (NIS) and 2) National Health and Nutrition Examination Survey (NHANES). The NIS was utilized to conduct univariate, bivariate, and multivariate analyses to determine the impact of prediabetes on short-term bariatric surgery outcomes, such as length of stay, hospital cost, complications, and in-hospital mortality. NHANES data were used to estimate the additional number of Medicare beneficiaries who would gain eligibility if the bariatric surgery NCD was expanded to include prediabetics. Findings: While patient characteristics varied greatly, resource outcomes and complications rates did not vary significantly between the groups. In-hospital mortality remained low (0.2%), complication rates were consistent (15%), and mean hospital charges were similar ($37,500). Specially, prediabetic patients did not have significantly different short-term outcomes relative to bariatric surgery patients with CMS-defined comorbidities (diabetes and/or hypertension). If CMS expanded coverage of bariatric surgery, an additional 108,961 prediabetic Medicare beneficiaries would be eligible and the expansion would cost CMS $21.9M to $54.8M for a given year.

Conculsions: Our results, combined with existing literature that quantifies the ability of the surgery to halt the progression of prediabetes to full-blown diabetes, provide justification for obese prediabetics to qualify for the surgery. The costs of an expansion would be more than offset by averted future diabetes-related hospitalizations. The evidence clearly indicates that obesity should be classified as an illness and treatment services should be covered. However knowing that such a policy change will demand time and debate, a more immediate recommendation is for CMS to expand the current bariatric surgery NCD to establish prediabetes as a qualifier for the surgery.