Understanding factors associated with loss of medicaid coverage among dual eligibles can help identify vulnerable enrollees.

For people who receive both Medicare and Medicaid benefits (dual-eligible beneficiaries), the loss of Medicaid coverage may lead to problems with care coordination, higher out-of-pocket expenses, or reduced access to services. Using administrative data, we followed 292,242 full-benefit and 91,020 partial-benefit dual eligibles from January 2009 through December 2011. Among those with full Medicaid benefits, 15.6 percent lost Medicaid coverage at least once, with more frequent losses among younger beneficiaries. Many of these losses lasted only one to three months and were followed by reinstatement. Loss of Medicaid coverage was more common (23.2 percent) among enrollees with partial Medicaid benefits. Medicare Current Beneficiary Survey data indicate that most dual eligibles who lost Medicaid coverage had no other source of supplemental insurance. Medicaid coverage is relatively stable among dual eligibles. However, some lose Medicaid for several months or more, putting them at risk for poor outcomes and potentially complicating their care, especially when it needs to be integrated under the two programs.