Using Medicaid claims data, this analysis examines adult preventable hospitalization rates across 21 states for the three most common types of preventable hospitalizations: asthma/chronic obstructive pulmonary disease (COPD), diabetes, and heart failure.

WHY THIS MATTERS

High rates of potentially preventable hospitalizations—those that should be largely prevented if ambulatory care is provided in a timely and effective manner— may signal a lack of access to high-quality outpatient care. They are also very expensive and, therefore, represent potentially preventable health care spending. This research provides new evidence on preventable hospitalization rates among Medicaid-covered nonelderly adults, including the extent of racial differences in preventable hospitalization rates, how preventable hospitalization rates compare by Supplemental Security Income (SSI) status, and the extent of variation across states in preventable hospitalization rates.

WHAT WE FOUND

• Pooled across 21 states, the three most common types of potentially preventable hospitalizations for Medicaid-enrolled adults were asthma/COPD (0.2 percent of enrollees had at least one such hospitalization in 2019), diabetes (0.4 percent of enrollees had at least one such hospitalization in 2019), and heart failure (0.2 percent of enrollees had at least one such hospitalization in 2019).
• For all three conditions, pooled across 21 states, preventable hospitalization rates were substantially higher for adults eligible for Medicaid through SSI compared with adults eligible for Medicaid through other pathways.
• Preventable hospitalization rates for heart failure were substantially higher for Black, non-Hispanic Medicaid-enrolled adults than for white, non-Hispanic Medicaid-enrolled adults in the pooled sample of 11 states where we could assess differences by race. The differences by race persisted even after adjusting for age, sex, managed care status, rurality, and state. Differences by race were small for asthma/COPD and diabetes preventable hospitalizations.
• Preventable hospitalization rates for all three conditions varied significantly by state. This was true even among adults eligible for Medicaid through SSI—for whom the eligibility thresholds are similar across most states—evidence that state variation is not entirely explained by differences in eligibility rules.

HOW WE DID IT

We used the 2018 and 2019 Transformed Medicaid Statistical Information System Analytic Files from the Centers for Medicare and Medicaid Services, which contain all enrollment, claims, and encounter data for Medicaid/Children's Health Insurance Program enrollees for this analysis.