In this population-based study of more than 9,500 older Blacks and Whites, we found racial differences in the association of education and health, but the pattern was an interesting hybrid of what we expected. We found that the association of education with markers of physical and cognitive health was similar in older Blacks and Whites with low levels of education. At higher levels of education, however, there was a significantly more positive association between years of education and these health outcomes among Blacks than among Whites. The net result of these findings was that there was a constant disadvantage in health for Blacks at lower levels of education, which began to attenuate with each additional year of education beyond approximately 12 years of education. When we adjusted for differences in chronic disease between Blacks and Whites, the results were unchanged, suggesting that disease-related pathways do not account for racial differences in the relationship between years of education and late-life functional health outcomes. Together, these findings suggest that the pattern of association between education and health differs between Blacks and Whites, such that Blacks may enjoy greater returns in functional health for additional education beyond high school (>12 years).
Although there were no racial differences in the association of education and health for those with less than a high school education, consistent with previous reports, there were large level differences with Blacks performing at a significantly lower level on both physical function and cognitive performance tests compared with similarly educated Whites (Manly et al., 1998
; Mehta et al., 2004
; Mendes de Leon et al., 2005
). One potential explanation for the level difference is the influence of social and environmental factors associated with being both of minority race and lower social class. That is, the less favorable social conditions due to poverty, compounded with the effects of racial discrimination due to minority status, may have combined to produce a chronic state of social disadvantage, which translated into more adverse health or poorer performance for Blacks. Another possible explanation is differences in the early educational experiences of Blacks and Whites. It has been well documented that educational facilities, resources, and opportunities were more limited for Blacks compared with Whites during the time that the present cohort would have received their primary education (e.g., Hall, Gao, Unverzagt, & Hendrie, 2000
; Williams, 1999
). For example, many Blacks would have been educated in segregated schools in southern US states where there were not only racial differences in public expenditures per pupil, but differences in other school-level variables such as length of school term, quality and experience of teachers, and access to quality books and other resources (Williams, 1999
). These disparate factors could have influenced the development and maintenance of cognitive skills that is reflected in lower test performance in old age. However, we also found significant level differences for physical function, suggesting that differences in educational quality and related factors associated with educational disparities may have had broader influences that permeated beyond cognitive health or that some other marker of social disadvantage is responsible for the differences in health.
Although we found that the association between education and health differed between Blacks and Whites, the pattern was not entirely consistent with the double jeopardy account. The effect of race seems constant across education from 4 through 12 years, but decreases with more education beyond 12 years. That is, the lines were parallel at lower levels of education and began to converge with additional education (i.e., beyond 12 years). One possibility for the flattening of the education–health relationship among Whites is a ceiling effect in this population. In contrast, a possible explanation for the positive slope observed in Blacks is that perhaps Blacks with higher education may have had different educational experiences when younger that placed them on a trajectory in later life that allowed them to engage in more cognitively stimulating occupations or have other lifetime experiences that translated into better overall health. Another possibility is that many Blacks may complete their education later in life after entering the workforce and therefore experience more benefits of education perhaps due to increased life experience compared with Whites who may be more likely to complete their education while young and without interruption. In fact, there is recent evidence that a higher percentage of Black high school dropouts return to school in later life compared with other races (2000 US Census report). Although only recently documented in the past decade or so, this would be a particularly viable explanation for our older cohort as educational opportunities have broadened since the Civil Rights era, allowing more Blacks to achieve more than they could in the past. Related to this, it is possible that there may be racial differences in the types of educational experiences at higher levels that we did not measure. That is, for respondents who reported more than 12 years of education, we do not know whether the additional years were for years in college or graduate school, community college, or vocational training.
Finally, it is possible that these data reflect a selection effect for Blacks at the higher levels of education. The Blacks in this cohort would have been college-aged during the pre-Civil Rights era (between 1946 and 1958). Given the lack of structural opportunities and overt racism that created barriers to achieving a higher education at that time, those who were able to complete high school and pursue a college education may have had to be particularly resilient and overcome greater challenges to achieve the same result. The positive slope for Blacks for physical and cognitive function may represent a hardier group of Blacks who survived the negative adverse experiences of being shut out of higher educational opportunities (Gibson & Jackson, 1995
). Related to this point, it is possible that we are seeing a selection effect due to differential mortality between Blacks and Whites prior to old age (Hayward et al., 2000
), again resulting in a hardier more resilient cohort of Blacks who were able to achieve more than their counterparts who did not make it to old age. Whatever the mechanism, the leveling off between education and health for Whites, but positive association for Blacks resulted in smaller overall level differences in health (and at least for physical function, better health) between Blacks and Whites at the highest levels of education.
Although relatively few studies have systematically examined the interaction of race and education on health outcomes across the full spectrum of education, our finding of a greater benefit for health indicators among Blacks with more education is consistent with others (e.g., Bandiera, Pereira, Arif, Dodge, & Asal, 2008
; Cagney & Lauderdale, 2002
; Freedman, Strogatz, Williamson, & Aubert, 1992
; Luo & Waite, 2005
; Shadlen et al., 2001
; Shadlen et al., 2006
). For example, Shadlen and colleagues
found a reduced magnitude of ethnic differences on a global cognitive measure for more highly educated Whites and African Americans compared with less educated, and in a later study, (Shadlen et al., 2006
) an attenuated risk of dementia in African Americans with more than 10 years of education. Similarly, both Cagney and Lauderdale
and Luo and Waite
reported that educational attainment had larger effects on cognitive function scores for African Americans than Whites. Finally, Freedman and colleagues
found smaller racial differences in the association of education and lipoprotein cholesterol in those with more education, and Bandiera and colleagues
, reported smaller differences in chronic asthma for those with greater economic resources.
Confidence in these findings is strengthened by several factors. First, our data are from a population-based sample of older adults with a wide spectrum of physical and cognitive function. It can be challenging to examine the intersection of race and SES in explaining and understanding health disparities in populations where there is little to no variation within group. Our sample included a higher proportion of Blacks than found in most studies and a broad range of education within Blacks from 4 to 24 years. In addition, the fact that Blacks and Whites were sampled from the same population enhanced our ability to make meaningful comparisons across race, and the large size of the population increased our power to do so. Second, we used performance-based measures of physical and cognitive function, that were both psychometrically sound and found to be valid and reliable from previous studies in this cohort (Mendes de Leon et al., 2005
; Wilson et al., 1999
). In addition, results generalized across both health measures, strengthening the potential impact of the findings.
These findings also have several important limitations. There are many factors during life that may affect health in late life, such as early life factors (Bowen, 2009
; Cohen, Doyle, Turner, Alper, & Skoner, 2004
; Everson-Rose, Mendes de Leon, Bienias, Wilson, & Evans, 2003
; Guralnik, Butterworth, Wadsworth, & Kuh, 2006
), behavioral factors in adulthood (Barnes, Mendes de Leon, Wilson, Bienias, & Evans, 2004
; Boyle, Buchman, Wilson, Bienias, & Bennett, 2007
), or health care utilization factors (Bowen & Gonzalez, 2008
). The current results pertain to racial differences in health in late life, and it is unclear if they have any relation to racial differences observed in health in early life. Second, because we included everyone with valid physical or cognitive function scores at baseline, we may have included individuals with mild forms of disease, which could bias our estimates of the association of education and health. However, in secondary models with cognitive function as the outcome, we excluded those persons with low cognitive function and the results were unchanged. Third, we used only one marker of SES. Although educational attainment is a principle measure of SES and is strongly associated with other SES indicators, other indicators, such as wealth may have yielded a different pattern of racial differences in the association of SES and health. Fourth, our population is from an urban setting in the Midwest, and so the findings may not be generalizable to aging populations in other types of settings in the United States. Fifth, as is true of any research study, particularly in older adults, it is possible that persons agreeing to enroll in our study may have had higher levels of education, which may have decreased our power to see racial differences at the low ends of education. Finally, our results could be due to various selection effects among the Blacks that we were not able to fully capture in this dataset. Although educated Blacks during the pre-Civil Rights era were predominantly from higher achieving or wealthier families, the passage of several federal mandates in the United States that allowed access to higher education for Blacks and the creation of several Historically Black Colleges and Universities made it possible for a broader spectrum of Blacks to attend college. It is possible that a significant proportion of Blacks from our sample could have benefited from such opportunities.
The current research adds to the growing body of evidence of interactive effects of SES and health as a function of race. Contrary to what we hypothesized, we found that although the association of education and health was similar among Blacks and Whites at low levels of education, the association was significantly more positive among Blacks than Whites at higher levels of education. The results suggest that Blacks with more than 12 years of education experience greater gains in two specific measures of physical and cognitive health compared with Whites with the net result being that racial differences in the association of education and functional health are smaller at higher levels of education than at lower levels. The results have important policy implications and suggest that continuing education or programs that promote higher education in minority populations may be helpful in reducing health disparities in old age. This could also have implications for late-life dementia risk as far as potential targeted educational interventions. Whether these patterns exist for other health outcomes or mortality risks and whether they influence trajectories of health over time need to be considered in future work.