Differences in Health Care Utilization, Process of Diabetes Care, Care Satisfaction, and Health Status in Patients With Diabetes in Medicare Advantage Versus Traditional Medicare.

OBJECTIVE: The objective of this study was to determine differences in health care utilization, process of diabetes care, care satisfaction, and health status for Medicare Advantage (MA) and traditional Medicare (TM) beneficiaries with and without diabetes. METHODS: Using the 2010-2016 Medicare Current Beneficiary Survey, we identified MA and TM beneficiaries with and without diabetes. To address the endogenous plan choice between MA and TM, we used an instrumental variable approach. Using marginal effects, we estimated differences in the outcomes between MA and TM beneficiaries with and without diabetes. RESULTS: Our instrumental variable analysis showed that compared with TM beneficiaries with diabetes, MA beneficiaries with diabetes had less annual health care utilization, including -22.4 medical provider visits [95% confidence interval (CI): -23.6 to -21.1] and -3.4 outpatient hospital visits (95% CI: -3.8 to -3.0). A significant difference between MA and TM beneficiaries without diabetes was only observed in medical provider visits and the difference was greater among beneficiaries with diabetes than beneficiaries without diabetes (-12.5 medical provider visits; 95% CI: -15.9 to -9.2). While we did not detect significant differences in 5 measures of the process of diabetes care between MA and TM beneficiaries with diabetes, there were inconsistent results in the other 3 measures. There were no or marginal differences in care satisfaction and health status between MA and TM beneficiaries with and without diabetes. CONCLUSIONS: MA enrollment was associated with lower health care utilization without compromising care satisfaction and health status, particularly for beneficiaries with diabetes. MA may have a more efficient care delivery system for beneficiaries with diabetes.

Disease-Specific Plan Switching Between Traditional Medicare and Medicare Advantage.

INTRODUCTION: Previous research has reported switching from traditional Medicare (TM) to Medicare Advantage (MA) plans increased from 2006 to 2011 at the aggregate level, and switching from MA plans to TM also increased. However, little is known about switching behavior among individuals with specific chronic diseases. OBJECTIVE: To examine disease-specific switching patterns between TM and MA to understand the impact on MA plans. METHODS: Using the 2006 to 2012 Medicare Current Beneficiary Survey, we examined disease-specific switching rates between TM and MA and disease-specific ratios of mean baseline total Medicare expenditures of beneficiaries remaining in the same plan (stayers) vs those switching to another plan (switchers), respectively. We focused on beneficiaries with 1 or more of 10 incident diagnoses. RESULTS: Beneficiaries with a new diagnosis of Alzheimer disease and related dementias, hypertension, and psychiatric disorders had relatively high rates of switching into MA plans and low rates of switching out of MA plans. Among those with new diagnoses of psychiatric disorders and diabetes, more costly beneficiaries (those with higher costs) switched into MA plans. For cancer, more costly beneficiaries remained in MA plans. CONCLUSION: Together, these results suggest that MA plans may have not only higher caseloads but also a more costly case mix of beneficiaries with certain diseases than historically was the case. Our findings can help inform MA plans to understand their beneficiaries' disease burden and prepare for provision of relevant services.