The Mortality Effects of Health Insurance for the Near-Elderly Uninsured

1. The Mortality Effects of Health Insurance for the Near-Elderly Uninsured Jose Escarce David Geffen School of Medicine at UCLA and RAND Coauthors: Daniel Polsky, Jalpa Doshi, Susan Paddock, Liyi Cen, Jeannette Rogowski, Willard Manning Funding Source: NIA (R01 AG024451-01)

2. Background • 46 Million Uninsured in the U.S. • 18% of total non-elderly population • 14.5% of near-elderly population • Benefits of health insurance well documented • Access to health care and use of health care services • Health and mortality • Hazard of mortality higher for the uninsured • Under-65 population: HR: 1.23 • Near-elderly population: HR: 1.43 • Medicare shown to increase use of health care services at 65

3. Objective • To determine whether there is a change in the hazard of mortality for the near-elderly uninsured when they acquire Medicare at age 65.

4. Health and Retirement Study (HRS) • A panel study of a nationally representative sample of people born between 1931-1941 and their spouses • Ages 51 to 61 in 1992 • 1992 through 2004 waves • Study sample: Subjects alive and interviewed at age 59/60 and in birth cohorts 1932-1937 (N=4,860) • Avoids left-censoring bias • Avoids attributing effect to cohorts

5. Sample Design

6. Graphical Representation of Research Design

7. Empirical Approach • To implement research design: • Use Cox proportional hazards model to estimate hazard ratio for the uninsured relative to the insured, both before age 65 and after age 65 (i.e., after Medicare enrollment) • Assess change in hazard ratio after age 65 compared with before age 65

8. Cox Regression Model • Outcome variable: Days until death or censored • Key Explanatory variables: • Uninsured at 59/60 • Uninsured at 59/60*Medicare enrollment • Insured—85.5% Uninsured—14.5% • Control Variables: • Model 1: Age, sex, race, education, region, self-rated general health at baseline • Model 2: Model 1 plus income, assets, employment status, baseline comorbidities, baseline ADLs, body mass index, alcohol use, smoking

9. Selected Baseline Characteristics

10. Survival Curves by Insurance Status

11. Hazard Ratio for Mortality:Uninsured Versus Insured * p<.05, ** p<.01

12. Sensitivity Analyses • Turn Medicare indicator “on” at age 65.5, 66, or 66.5 instead of 65 (to capture lagged effects of Medicare on mortality) • Use time-varying health status measures as explanatory variables • Results: No change in findings

13. Conclusions • People who are uninsured in late middle age have higher mortality rates than their insured counterparts • This difference in mortality rates is partly explained by other characteristics of the two groups • The magnitude of the difference between the two groups is unchanged after the uninsured enroll in Medicare at age 65 • This finding is robust to a wide range of sensitivity analyses

14. Implications • For people who are uninsured in late middle age, Medicare may come too late to make a difference in their health and mortality trajectories • Whether those trajectories can be modified through earlier receipt of insurance is a crucial question • The insured and uninsured in late middle age differ on a range of personal characteristics that are correlated with health

18. Sample Design

19. Background • Medicare increases use of health care services at 65 • Preventive services • Doctor visits and hospital admissions • Greater increases in health care service use among the previously uninsured • Effect of Medicare on health • Enactment of Medicare • No aggregate impact on mortality • Reduction in mortality • Medicare at 65 for the uninsured • No significant improvement in health status relative to the insured

20. Uninsured Hazard of Mortality from Cox Proportional Hazard Model