Effect of State-Led Delivery System and Payment Reforms on Population-Level Detection and Management of Diabetes

Objective: The Center for Medicare and Medicaid Services’ State Innovation Models Initiative (SIM) invested more than $1 billion to test state-led delivery system and payment reforms that can affect diabetes care management. We examined whether SIM implementation between 2013 and 2017 was associated with diagnosed diabetes prevalence and with hospitalization and 30-day readmission rates among diagnosed adults. 

Research Design and Methods: The quasi-experimental design compares study outcomes before and after SIM in 12 SIM states versus 5 comparison states using difference-in-differences (DiD) regression models of 21,055,714 hospitalizations for adults ages 18 or older diagnosed with diabetes in 889 counties from 2010-2017 across the 17 states. For readmissions analyses, CITS models included 11,812,993 hospitalizations from a subset of 9 states.

Results: Diagnosed diabetes prevalence changes were not significantly different for SIM states and comparison states. Hospitalization rates were inconsistent across models with DiD estimates ranging from -5.34 to -0.37 and from -13.16 to 0.92, respectively. The CITS results indicate that SIM states had greater increases in odds of 30-day readmission during SIM implementation compared to comparison states (Round 1: adjusted odds ratio (AOR)=1.07, 95% confidence interval (CI)=1.04, 1.11, p<0.001; Round 2: AOR=1.06, 95% CI=1.03, 1.10, p=0.001).

Conclusions: SIM was not sufficiently focused to have a population-level effect on diabetes detection and management. SIM states had greater increases in 30-day readmissions for adults with diabetes than comparison states, highlighting potential unintended effects of engaging in the multi-payer alignment efforts required of state-led delivery system and payment reforms.