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Health of previously uninsured adults after acquiring Medicare coverage
J Michael McWilliams1, Ellen Meara, Alan M Zaslavsky
1Division of General Medicine and Primary Care, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA.
Context:
Uninsured near-elderly adults, particularly those with cardiovascular disease or diabetes, experience worse health outcomes than insured adults. However, the health benefits of providing insurance coverage for uninsured adults have not been clearly demonstrated.
Objective:
To assess the effect of acquiring Medicare coverage on the health of previously uninsured adults.
Design And Setting:
We conducted quasi-experimental analyses of longitudinal survey data from 1992 through 2004 from the nationally representative Health and Retirement Study. We compared changes in health trends reported by previously uninsured and insured adults after they acquired Medicare coverage at age 65 years.
Participants:
Five thousand six adults who were continuously insured and 2227 adults who were persistently or intermittently uninsured from ages 55 to 64 years.
Main Outcome Measures:
Differential changes in self-reported trends after age 65 years in general health, change in general health, mobility, agility, pain, depressive symptoms, and a summary measure of these 6 domains; and adverse cardiovascular outcomes (all trend changes reported in health scores per year).
Results:
Compared with previously insured adults, previously uninsured adults reported significantly improved health trends after age 65 years for the summary measure (differential change in annual trend, +0.20; P = .002) and several component measures. Relative to previously insured adults with cardiovascular disease or diabetes, previously uninsured adults with these conditions reported significantly improved trends in summary health (differential change in annual trend, +0.26; P = .006), change in general health (+0.02; P = .03), mobility (+0.04; P = .05), agility (+0.08; P = .003), and adverse cardiovascular outcomes (-0.015; P = .02) but not in depressive symptoms (+0.04; P = .32). Previously uninsured adults without these conditions reported differential improvement in depressive symptoms (+0.08; P = .002) but not in summary health (+0.10; P = .17) or any other measure. By age 70 years, the expected difference in summary health between previously uninsured and insured adults with cardiovascular disease or diabetes was reduced by 50%.
Conclusion:
In this study, acquisition of Medicare coverage was associated with improved trends in self-reported health for previously uninsured adults, particularly those with cardiovascular disease or diabetes.
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