The authors investigated whether coronary heart disease (CHD) risk factors or socioeconomic status (SES) explain the racial differences in CHD mortality using data from the 1986 National Mortality Followback Survey. Cases of CHD were selected from this survey and were classified as sudden, non-sudden, and other (unknown). Cases were compared with a general population group that was identified through the 1985 National Health Interview Survey (NHIS), a multi-stage probability sample that represents non-institutionalized civilians in the United States.

Age- and gender-adjusted rates of sudden, non-sudden and other coronary deaths were approximately twice as high among younger (25 to 55 years for women and 25 to 45 years for men) African Americans as they were among younger Caucasians (rates=10.3, 7.6 and 5.5 per 100,000 for African Americans and 5.4, 4.1 and 2.5 per 100,000 for Caucasians). Death rates among older African American adults were similar to those among older Caucasian adults. The excess age- and gender-adjusted risks for sudden, non-sudden and other coronary deaths for African Americans compared with Caucasians declined by nearly 50% after adjustment was made for SES (family income, occupational status, or education level). Smaller declines were observed after adjustment for coronary risk factors. However, after adjustment for all factors measured in this study, some risk for each type of coronary death was still not explained.

The authors note that indicators of low SES account for most of the excess premature coronary heart disease mortality among African Americans and suggest that "low SES may be a marker for insufficient medical care." They conclude that, "public health efforts to address premature mortality among African Americans should address broader social issues such as poverty, unemployment, and educational attainment."

With regard to the 20-50% of the excess mortality for coronary health disease that was not accounted for, the authors suggest that survey measurement errors and psychological and social factors might also play a role.

The relative importance of SES and coronary risk factors was not specifically tested in this analysis; therefore, readers should be careful not to interpret these findings as an indication that SES is more important that other coronary risk factors. Additionally, potential race differences in incidence of CHD and survival were not discussed.