OBJECTIVES: Dual-eligibles are elderly and disabled under age 65 individuals who are entitled to Medicare and Medicaid.   CMS has instituted a state demonstration program to test capitated and managed FFS financial alignment care models for duals.  Limited research exists on the differences between the two dual subpopulations – elderly and disabled, which could prove problematic for benefit design consideration if the duals are treated as a homogenous group.  The objective of this study was to compare elderly vs disabled duals across demographic, morbidity, healthcare utilization, and drug spending measures.   METHODS: Cross-sectional analysis comparing profiles of disabled (n=90,894) and elderly (n=126,752) fee-for-service beneficiaries with continuous 12-month dual-eligibility, or until alive in the 2007 5% Medicare files. Chi-square and t-tests were conducted to measure statistically significant differences across measures of interest between elderly and disabled duals.   RESULTS:  Elderly duals were more likely to be female and suffer from chronic conditions like CHF, while disabled duals were more likely to have mental disorders like depression.  Disabled duals had significantly higher rates of ER use (8.4% vs 6.4%) and lower rate of hospitalization (31.9% vs 24.5%) than elderly duals.  Compared to the disabled, elderly duals had significantly higher rates of Part D brand drug use (88% vs 81%), but lower use of drugs typically placed on Part D specialty tiers (10% vs 13%). Significant differences existed in the types of drug classes frequently used by the two groups.  Large differences in spending across all types of medical services and drug categories across the two groups were observed.   CONCLUSIONS: There are significant differences in demographic, morbidity, healthcare utilization, and drug spending measures across the elderly vs. disabled duals. Recognizing the differences between sub-populations of dual eligibles is critically important and a “one size fits all” approach may unintentionally create hardships and be detrimental to the well-being of the duals.