K. G. Bennett1, M. E. Smith1, N. F. Matusko1, J. F. Waljee1, N. H. Osborne1, P. K. Henke1 1University Of Michigan,Department Of Surgery,Ann Arbor, MI, USA
Introduction:
In 2001, the state of New York expanded Medicaid coverage, providing access to care for thousands of previously uninsured patients. Although these policy changes can enhance the opportunity for obtaining care, little is known regarding care utilization, especially amongst patients with vascular disease and critical limb ischemia for whom access to procedures may prevent limb loss. We sought to measure the impact of Medicaid expansion on the rates of total vascular procedures, open procedures, endovascular procedures, and amputations.
Methods:
We examined discharge records from the 1998-2006 State Inpatient Databases of New York (intervention) and Arizona (control). Discharge records of interest were identified using ICD-9 vascular procedure codes. To measure the impact of Medicaid expansion on the rates of total vascular, open vascular, and endovascular procedures, as well as amputations, we used a difference-in-difference analysis to compare the number of procedures performed per admission within each state. We used logistic regression, truncated poisson, and zero-inflated poisson regression to model each outcome while adjusting for relevant patient covariates.
Results:
In this cohort of 112,624 patients undergoing vascular procedures, the difference-in-difference estimator demonstrated that expansion of Medicaid coverage was associated with lower odds of mortality (OR 0.77, p=0.043), but this became insignificant after controlling for patient-level covariates (OR 0.92, p=0.5). The difference-in-difference estimators also demonstrated that Medicaid expansion was associated with lower incidence rate ratios of total vascular procedures (IRR 0.65, p<0.001) and open vascular procedures (IRR 0.92, p=0.002), but a higher incidence rate ratio of endovascular procedures (IRR 1.13, p<0.001). There was no change in the incidence rate ratio of amputations (IRR 1.02, p=0.53). In patients with critical limb ischemia (N =12,668), the difference-in-difference estimators were also significant, demonstrating that expansion was associated with a lower incidence rate ratio of total procedures (IRR 0.59, p<0.001) and endovascular procedures (IRR 0.59, p<0.001) but a higher incidence rate ratio of amputations (IRR 1.43, p=0.001) and higher odds of mortality (OR 2.21, p=0.032).
Conclusion:
After Medicaid expansion, the rates of total vascular procedures decreased, with no impact on amputations rates in New York. Moreover, the utilization of interventions that could prevent amputations in patients with critical limb ischemia did not increase. Thus, while Medicaid expansion may improve access to care, significant barriers and disparities continue to prevent appropriate utilization of limb-saving procedures.