Objective: To compare mortality in persons with employer-provided health insurance, Medicare, Medicaid, military health benefits, other private health insurance, and no health insurance, before and after adjustment for income and employment status.
Design: Cohort study using national survey data containing information on social, economic, and demographic factors and health insurance, with deaths identified through matching to the National Death Index resulting in a mortality follow-up period of 5 years.
Setting: Noninstitutionalized population of the United States.
Participants: Approximately 150,000 respondents to national surveys conducted by the US Bureau of the Census (Current Population Surveys), aged 25 to 64 years.
Results: After adjustment for age and income, persons with Medicare and Medicaid had the highest mortality in comparison with those with employer-provided insurance, with relative risks generally greater than 2. With adjustment for age and income, persons without insurance had higher mortality than those with employer-provided insurance, with relative risks of 1.2 for white men and 1.5 for white women. These relationships held after adjustment for employment status, with the working uninsured showing mortality between 1.2 and 1.3 times higher than that of the working insured. Mortality was higher in those with lower incomes after adjustment for insurance status. Those with annual income of $10,000 or less per year had mortality about two times that of persons with incomes greater than $25,000 per year.
Conclusion: Mortality was lowest in employed persons with employer-provided health insurance. The higher mortality in those with public insurance or with no insurance reflects an indeterminate mix of selection on existing health status and access to medical care.