ArticlesDecember 16, 2008
    Author, Article, and Disclosure Information

    Many low-income U.S. citizens experience interruptions in health insurance coverage.


    To determine the rate of hospitalization for ambulatory care–sensitive conditions among Medicaid beneficiaries with interruptions in coverage.


    Retrospective cohort study.


    California Medicaid population.


    4 735 797 adults in California age 18 to 64 years who received a minimum of 1 month of Medicaid coverage between 1998 to 2002.


    Time to hospitalization for an ambulatory care–sensitive condition.


    Sixty-two percent of Medicaid beneficiaries experienced at least 1 interruption in coverage during the study period. The 3 most common ambulatory care–sensitive conditions resulting in a hospitalization were heart failure, diabetes, and chronic obstructive pulmonary disease. Interruptions in coverage were associated with a higher risk for hospitalization for an ambulatory care–sensitive condition (adjusted hazard ratio, 3.66 [95% CI, 3.59 to 3.72]; P < 0.001). In subgroup analyses, the association between interrupted coverage and hospitalization was stronger for beneficiaries eligible through the Temporary Aid to Needy Families program (adjusted hazard ratio, 8.56 [CI, 8.06 to 9.08]) than for beneficiaries eligible through the Supplemental Security Income program (adjusted hazard ratio, 1.72 [CI, 1.67 to 1.76]), who typically retain Medicare coverage even when their Medicaid coverage is interrupted.


    The study lacked information on why interruptions occurred and whether beneficiaries with interruptions transitioned to other insurance coverage.


    Interruptions in Medicaid coverage are associated with a higher rate of hospitalization for ambulatory care–sensitive conditions. Policies that reduce the frequency of interruptions in Medicaid coverage might prevent some of the health events that trigger hospitalization and high-cost health care spending.


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