1. Improved Treatment of Ischemic Heart Disease and Disability and Death in the Elderly Kate Stewart Mary Beth Landrum David Cutler Academy Health June 27, 2006

2. Background Changes in health/disability among population aged 65+ over the past 20 years: Changes in health/disability among population aged 65+ over the past 20 years: Prevalence of chronic diseases increased Prevalence of chronic diseases increased Disability decreased Disability decreased

3. Background Does medical care explain some of the disability decline? Does medical care explain some of the disability decline? Focus: Ischemic Heart Disease Focus: Ischemic Heart Disease Prevalence increases with age Prevalence increases with age Medical advances reduced mortality by 40-66% between 1968-2000 Medical advances reduced mortality by 40-66% between 1968-2000 Clinical trials: improved survival and quality of life Clinical trials: improved survival and quality of life Little understanding of effect of improved treatment on population disability Little understanding of effect of improved treatment on population disability

4. Data: National Long Term Care Survey Medicare-linked data: hospitalizations & vital status Medicare-linked data: hospitalizations & vital status Analytic Cohort: 1989 1994 1999 1984 1989 1994 IHD hospitalization Health Status at Follow-Up Disabled Dead Alive & Non-Disabled N = 54,453 Baseline Survey N = 3,842

5. Data: Medical Treatment Cardiovascular Cooperative Project (CCP), 1994-1995 Cardiovascular Cooperative Project (CCP), 1994-1995 Share of appropriate AMI patients within a hospital referral region (HRR) who received Share of appropriate AMI patients within a hospital referral region (HRR) who received Aspirin Aspirin Ace-Inhibitors Ace-Inhibitors Beta Blockers Beta Blockers Reperfusion within 12 hours after AMI Reperfusion within 12 hours after AMI Invasive procedures variable Invasive procedures variable Share of respondents with procedures on the heart, pericardium or vessels of the heart Share of respondents with procedures on the heart, pericardium or vessels of the heart

6. Analytic Strategy Evaluate whether IHD patients living in HRRs with more intensive treatment had better outcomes Evaluate whether IHD patients living in HRRs with more intensive treatment had better outcomes Minimize selection problems Minimize selection problems Natural experiment Natural experiment Exposure = treatment intensity Exposure = treatment intensity Estimate decline in disability attributable to improved treatment Estimate decline in disability attributable to improved treatment Simulate health outcomes by varying levels of care Simulate health outcomes by varying levels of care

7. Multinomial Models Model 1: Y = Xβ + λ 1 Year89 + λ 2 Year94 Model 1: Y i,j,t = X i,t β + λ 1 Year89 + λ 2 Year94 Model 2: Y = Xβ + λ 1 Year89 + λ 2 Year94 + Model 2: Y i,j,t = X i,t β + λ 1 Year89 + λ 2 Year94 + γCCP Tx + δCCP Tx*Year + τProcs γCCP Tx j + δCCP Tx j *Year + τProcs j

8. Results: Multinomial Models Model 1: Without Tx*Model 2: With Tx* Disabled vs. Non- Disabled Dead vs. Non- Disabled Disabled vs. Non-Disabled Dead vs. Non-Disabled Odds Ratios λ λ 1 : Year89 0.830.77 # 0.900.91 λ λ 2 : Year94 0.70 # 0.60 # 0.830.85 Joint F-test: treatments -- P <0.01 *1984 is reference year # p <0.05 ^ ^ ^

9. Results Simulations by percentiles of care: Number alive & non-disabled relative to observed Simulations by percentiles of care: Number alive & non-disabled relative to observed

10. Limitations Potential unmeasured confounding: Potential unmeasured confounding: Area-level treatment variables Area-level treatment variables Changes in severity of hospital admissions over time Changes in severity of hospital admissions over time Differences in claims coding over time Differences in claims coding over time CCP treatment variables measured at 1 time point only CCP treatment variables measured at 1 time point only

11. Conclusions Elderly IHD patients were more likely to be alive & non-disabled over time Elderly IHD patients were more likely to be alive & non-disabled over time Increased treatment explains approx. 50% of the disability decline Increased treatment explains approx. 50% of the disability decline 21% more elderly IHD patients would have been alive and non-disabled in 1999, if all lived in high treatment areas 21% more elderly IHD patients would have been alive and non-disabled in 1999, if all lived in high treatment areas Improved care and outcomes possible through increased use of appropriate IHD treatments Improved care and outcomes possible through increased use of appropriate IHD treatments

12. Funding Funding: Funding: National Institute on Aging (P30 AG12810 and R01AG019805) National Institute on Aging (P30 AG12810 and R01AG019805) Mary Woodard Lasker Charitable Trust Mary Woodard Lasker Charitable Trust Michael E. DeBakey Foundation Michael E. DeBakey Foundation

15. Results: Health Status at Follow-Up *p-value calculated from pearson chi-square test of independence, corrected for the complex survey design. Estimates adjusted to the age and sex distribution of the 1999 population of Medicare beneficiaries 198419891994Difference 1994-1984 p-value* % Disabled23.122.321.2-1.9 0.004 % Dead37.734.031.0-6.7 % Alive & Non- disabled 39.243.747.88.6

16. Area-Level Treatment Percent Invasive Procedures Percent Invasive Procedures 10 th percentile: 6% in 1984 and 18% by 1994 10 th percentile: 6% in 1984 and 18% by 1994 90 th percentile: 40% in 1984 and 70% by 1994 90 th percentile: 40% in 1984 and 70% by 1994 Percentiles of Care: 10 th 90 th Beta Blockers 34.768.7 Ace-Inhibitors46.774.0 Aspirin69.784.4 Reperfusion56.277.6 CCP Measures