Elizabeth H. Bradley, PhD Yale School of Public Health

1. Racial and Ethnic Differences in the Quality of Care for Patients Hospitalized with Myocardial Infarction, 1999-2002. Elizabeth H. Bradley, PhD Yale School of Public Health

2. Acknowledgements This work is funded by -National Heart, Lung, and Blood Institute (#R01HS10407-01) -Patrick & Catherine Weldon Donaghue Medical Research Foundation (#02-102) -Claude D. Pepper Older Americans Independence Center at Yale (#P30AG21342)

3. Collaborators Jeph Herrin, PhD Yongfei Wang, MS Robert McNamara, MD Tashonna Webster, MPH David Magid, MD Martha Blaney, PharmD Eric Peterson, MD John Canto, PhD Charles Pollack, MD Harlan Krumholz, MD

4. Background Many studies demonstrate different patterns of cardiovascular care by racial and ethnic groups (e.g., referral for cardiac catheterization, use of invasive tests) Few have investigated the relative contributions of socio-demographic, economic, clinical, and health system features to this racial/ethnic disparities

5. Why is this important? Elimination of racial/ethnic disparities in care is a national priority (IOM, CDC, AHRQ) To address disparities, we have to know their source and causal mechanisms

6. Research objectives We sought to: Characterize racial/ethnic differences in quality of cardiovascular care for patients hospitalized with acute myocardial infarction (AMI) Examine factors that mediate or explain observed racial/ethnic differences in quality of care

7. Measuring quality of care for AMI Which quality indicator to use? - Evidence based - Well established in clinical guidelines - Substantial variation in country - Involving hospital “systems”

8. Time is muscle! Quality indicator endorsed by American Heart Assoc is time to acute reperfusion - 30 minutes door to drug (“lytics”) - 90 minutes door to balloon (PCI)

9. Study design and sample Retrospective, observational study using patient data from the National Registry of Myocardial Infarction, 1999-2002 - fibrinolytic cohort n=73,032; 1,052 hospitals - PCI cohort n=37,143; 434 hospitals American Hospital Association Annual Survey of Hospitals, 2000.

10. Measurement: outcome Door-to-drug time; door-to-balloon time as continuous measures Log transformed for performing parametric analyses, in order to account for the skewness of its distribution Summary measures thus reported as geometric (i.e., logarithmic) mean

11. Measurement: race/ethnicity Recorded by admissions clerk or nurse; a set of dummy variables White African American/Black Hispanic Asian/Pacific Islander American Indian/Alaska native Other/Unknown

12. Statistical analysis We examined overall geometric means for door to treatment times for each racial/ethnic group, i.e., “crude” differences To explore how crude differences might be mediated by other factors, we employed multivariate, hierarchical models (built in sequence of steps)

13. Results Crude rates (mins)DTDDTB TARGET 30 mins 90 mins White 33.8 103.4 Afr Am 41.1** 122.3** Hispanic 36.1** 114.8** Asian 37.4** 105.8 Am Ind 36.4 101.2 Other 33.9 101.2 ** P-value < 0.01

14. Door to balloon times: AfricanAmerican (differences from white) Race/ethnicity effects Compared to white Overall crude 18.9 minutes +Hosp cluster effects 12.6 minutes +Age, sex, ins 12.9 minutes +Clinical char 11.1 minutes +Full model 8.6 minutes

15. Door to balloon times: AfricanAmerican (differences from white) Of the 18.9 minute crude difference, - 33.3% (18.9 -12.6/18.9) accounted for by hospital-specific effect - 21.2% (12.6 - 8.6/18.9) accounted for by patient-level factors and hospital characteristics - 45.5% (8.6/18.9) independently related to race/ethnicity

16. Door to balloon times: Hispanic (differences from white) Race/ethnicity effects Compared to white Overall crude 11.4 minutes +Hosp cluster effects 3.2 minutes +Age, sex, ins 4.9 minutes +Clinical char 4.4 minutes +Full model 3.7 minutes

17. Door to balloon times: Hispanic (differences from white) Of the 11.4 minute crude difference, - 71.9% (11.4 - 3.2/11.4) accounted for by hospital-specific effect - some negative confounding by sex, age - 32.5% (3.7/11.4) independently related to race/ethnicity

18. Discussion Marked differences in time to reperfusion by racial/ethnic group Especially apparent for African Americans, whose door-to-drug and door-to-balloon times are 20% longer than for patients identified as white

19. Discussion Is the racial/ethnic disparity a result of: - differential treatment inside the hospital - selection to different types of hospitals?

20. Discussion We found that a substantial portion of the differences in time to acute reperfusion time was explained by accounting for the hospital to which patients were admitted, especially for Hispanic individuals (~70% of the door-to-balloon time disparity) but also for African American patients (~30% of the disparity)

21. Implications Efforts to raise awareness of racial/ethnic disparities are important; however… These data suggest need for parallel efforts directed at improving the care at hospitals where minority groups receive care A systemic approach will be needed