Comparison of opioid analgesic-related mortality between those enrolled or not enrolled in Medicaid shows considerably higher death rates and a more rapid increase in mortality among Medicaid enrollees. The consistently higher age-adjusted death rates for poisonings involving opioid analgesics among Medicaid enrollees (after stratifying data by sex) suggest that differences in age and sex distributions do not underlie these Medicaid/non-Medicaid differences. Other factors, such as the greater prevalence of mental illness and substance abuse in the Medicaid population (6), might contribute to the observed differences.

via Poisoning Deaths Involving Opioid Analgesics — New York State, 2003–2012.

Maybe the title should be Socioeconomic Status and Death.