Introduction: About 92% of US older adults have at least one chronic disease or medical condition and 77% have at least two. Low-income and uninsured adults in particular experience a higher burden of comorbidities, and the Medicaid expansion provision of the Affordable Care Act was designed to improve access to healthcare in this population group. However, a significant number of US states have declined expansion. The purpose of this study is to determine the distribution of low-income and uninsured adults in expanded versus non-expanded states, and evaluate the prevalence of comorbidities in both groups. Methods: Data from the 2013 Behavioral Risk Factor Surveillance System (BRFSS) dataset was analyzed, and Medicaid expansion status was assessed from the Center for Medicare and Medicaid Services report on State Medicaid and CHIP Income Eligibility Standards. Next, age adjusted mean number of comorbidities between expanded and non-expanded states was compared, with adjustment for socio-demographic differences. Results: Expanded states had a higher proportion of adults with income of at least $50,000 per year (39.6% vs. 35.5%, p < 0.01) and a lower proportion of individuals with no health insurance coverage (15.2% vs. 20.3%, p < 0.01) compared with non-expanded states. Among the uninsured, there was a higher proportion of obese (31.6% vs. 26.9%, p < 001), and higher average number of comorbidities (1.62 vs. 1.52, p < 0.01) in non-expanded states compared to expanded states. Overall, the prevalence of comorbidities was higher among BRFSS participants in states that did not expand Medicaid compared with those in expanded states. Conclusion: States without Medicaid expansion have a greater proportion of poor, uninsured adults with more chronic diseases and conditions.