Impact of “Defensive Medicine” on the Costs of Diabetes and Associated Conditions

Geographic variation in health care spending is typically attributed to differences in patient health status and provider practice patterns. While medicolegal considerations (i.e., “defensive medicine”) anecdotally impact health care spending, this phenomenon is difficult to measure. The purpose of this study was to explore the association between the medicolegal environment and Medicare costs for diabetes and associated conditions of interest to vascular surgeons. Specifically, we hypothesized that an adverse medicolegal environment is associated with higher per capita Medicare costs for diabetic patients. Medicare data including the most recent (2018) Medicare Geographic Variation Public Use Files and Chronic Conditions Data Files were linked to National Practitioner Data Bank files from the preceding 5 years (2013–2017), in addition to the US census data and American Medical Association workforce statistics. The state-level medicolegal environment was characterized by K-means clustering across a panel of metrics related to malpractice payment magnitude and prevalence. Per capita Medicare spending for diabetes was compared across 5 distinct medicolegal environments. Costs were standardized and risk-adjusted to account for known geographic variation in health care costs and patient population. Analysis of variance was applied to unadjusted data, followed by multivariate regression modeling. Readmission rates, per capita imaging studies, per capita tests, per capita procedures, and lower extremity amputation rates were compared between the least litigious quintile from the K-means clustering and the 2 most litigious quintiles. The median unadjusted Medicare per capita expenditure on diabetic patients was $15,963 ($14,885–$17,673), ranging from $13,762 (Iowa) to $21,865 (D.C.). A 1.6-fold variation persisted after payment standardization. Cluster analysis based on malpractice-related variables yields 5 distinct medicolegal environments, based on litigation frequency and malpractice payment amounts. Per capita spending on diabetes varied, ranging from $15,799 in states with low payments and infrequent litigation to $18,838 in states with the most adverse medicolegal environment (P