Increased Breast Cancer Survival Increased Breast Cancer Survival Differentials by Race in AmericaDifferentials by Race in America

Historic Observational Evidence Consistent With a Health Insurance

Hypothesis, 1975 to 2000

Research ObjectiveResearch Objective

To learn from our experiences of the past generation whether or not health care outcomes (resources) have become more or less equitably distributed

- African American vs. white people

- In metropolitan Detroit

- With breast cancer (sentinel outcome)

Historical Context: 1975 to 2000Historical Context: 1975 to 2000

- US health care system is multi-tiered: Uninsured, underinsured, Medicaid, Medicare, and array of private coverages

- Time of great systemic changes- Managed care & for-profit proliferation- Uninsured population nearly doubled (increased from 24 to 44 million among those < 65 years of age)

Theoretical Context: Systematic Theoretical Context: Systematic Literature ReviewLiterature Review

- Race and socioeconomic status (SES) are strongly associated with health insurance statuses (ORs 2.0 to 15.0).

- Race, SES and health insurance statuses are all strongly associated with cancer screens, stages at diagnosis and access to treatments (ORs 2.0 to 5.0).

Research Questions Research Questions

Given the near 20% improvement in breast cancer survival during the study period:

1. Has this medical advance been enjoyed equitably by African American and white women?

2. Is there a particular African American disadvantage among those not yet eligible for Medicare?

MethodsMethods

Using Historical Cohorts and Focusing on Interactions, Rather

Than Mere Main Effects

Sample DesignSample Design

- Detroit Cancer Registry, SEER- Detroit metro: 3 counties, 4 million+ pop- Primary invasive breast cancer cases- Women, 25 years of age and older- Entire most valid cohort

1975 to 2000 inclusive followed until December 31, 2001

- N = 57,66810,237 African American and 47,431 White people

Analytic PlanAnalytic Plan

- 1970s & 1990s cohorts compared, e.g., 1975-80 followed until 1986 vs. 1990-95 until 2001 for 5-year survival analyses

- Analyses of survival used proportional hazards models.

- Analyses of stages of disease at the time of diagnosis and treatments (1st year post-diagnosis) used logistic regression models.- All models were adjusted for age and year of diagnosis.

Results

Significantly Increased Racial Group Breast Cancer Survival, Stage and

Treatment Differentials

Race By Cohort InteractionsRace By Cohort Interactionsaa on on Survival: Odds Ratios (95% CIs)Survival: Odds Ratios (95% CIs)

Main Effects of Race Within CohortMain Effects of Race Within Cohort 1970s1970s 1990s1990s

1-yr 1.83 (1.60,2.09) 2.07 (1.86,2.31)3-yr 1.67 (1.51,1.86) 2.09 (1.93,2.26)5-yr 1.64 (1.46,1.84) 1.94 (1.79,2.16)10-yr 1.64 (1.40,1.91) 1.88 (1.66,2.13)

a All minimally significant at p < .05).

Race By Age By Cohort Interaction Race By Age By Cohort Interaction on 5-Year Survival: ORs (95% CIs)on 5-Year Survival: ORs (95% CIs) Race By Age Within CohortRace By Age Within Cohort AgeAge 1970s1970s 1990s1990s < 65 1.60 (1.39,1.84) 2.06 (1.85,2.30)65 + 1.74 (1.41,2.16) 1.79 (1.58,2.04)

The 3-way interaction was significant at p < .05).

Race By Age By Cohort Interaction Race By Age By Cohort Interaction on Local Disease: ORs (95% CIs)on Local Disease: ORs (95% CIs)

Race By Age Within CohortRace By Age Within Cohort AgeAge 1970s1970s 1990s1990s < 65 1.24 (1.12,1.37) 1.46 (1.35,1.58)65 + 1.58 (1.36,1.84) 1.56 (1.41,1.72)

The 3-way interaction was significant at p < .05).

Race By Age By Cohort Interactions Race By Age By Cohort Interactions on Treatmentson Treatments

Similar interactions were observed on receipt of surgery (localized disease), radiation therapy (local & regional), chemotherapy and hormone therapy (regional disease).

All were indicative of particularly increased African American disadvantages among those not yet eligible for Medicare.

Interactions Seem to Reflect Interactions Seem to Reflect Sociologic, Not Biologic PhenomenaSociologic, Not Biologic Phenomena

When four socioeconomic variables were entered into the analytic models each of the previously significant interaction terms did not enter

(at p < .05).

The four measures were census tract- based compositional (prevalence of poor and near poor [200% poverty criterion] people) and contextual (median home and rental values) measures of social position.

DiscussionDiscussion

The Evidence Supports

Race as a Social Construction &

The Implementation of Policies That Would Ensure All Americans Access to

Timely Diagnosis & the Best Available Treatments

Summary Summary

African American women with breast cancer have not fully enjoyed contemporary survival advances. Relative to white patients they are more disadvantaged today than they were 25 years ago.

Alternative Explanations:- Social policies and structures affecting

health insurance access have changed drastically during this time frame.

- Gene-based, biologically-mediated (tumor) characteristics have not.

Policy ImplicationsPolicy Implications

- Race and income (type of insurance one has) still matter very much in American health care.

- Racial and socioeconomic inequities could probably be eliminated in large measure by providing universal access to all: - The young and the old- The poor and the rich- People of color and white people.