Social and economic disadvantages play a significant role in why blacks face a much higher risk than whites of developing cognitive impairment later in life, indicates a national study led by a Michigan State University (MSU) sociologist.
The odds that blacks will develop cognitive impairment, including dementia, in later life were 2.52 times greater than the odds for whites. Much of that racial disparity was explained by childhood disadvantages, such as growing up poor and in the segregated South, and lower socioeconomic status in adulthood, particularly educational attainment.
Surprisingly, racial differences in health problems, such as heart disease and diabetes, and health behaviors, such as smoking and drinking, did not explain much of the racial gap in cognitive impairment, said Zhenmei Zhang, an MSU associate professor of sociology.
While the findings do not fully explain blacks' higher risk of cognitive impairment, they point to a strong need for policymakers to focus more on reducing racial gaps in socioeconomic resources over the lifespan, she said. The federally funded study was published online today and will appear in the June print edition of the Journal of Health and Social Behavior.
"Social policies such as increasing educational resources in low-income communities, providing economic support to poor students and their families, improving graduation rates in high schools and colleges, and eliminating discrimination against blacks in the job market may significantly reduce racial disparities in cognitive impairment in later life," Zhang said.
Zhang and her colleagues analyzed survey data from 8,946 participants in the Health and Retirement Study. The information was collected in multiple waves over a 12-year period (1998-2010). All participants were 65 or older in 1998.
Once the researchers took the various socioeconomic factors into account, the odds ratio of cognitive impairment between blacks and whites — or the racial gap — was reduced considerably, from 2.52 to 1.45. That means socioeconomic factors explained a significant amount of the racial gap.
Cognitive impairment among the elderly is a growing problem — spending on dementia care alone exceeds $100 billion a year in the United States — but it hits blacks particularly hard, Zhang noted. The Alzheimer's Association has identified Alzheimer's disease among blacks as an emerging public health crisis.
"As people live longer and longer, it becomes an even bigger issue," Zhang said.
Her co-authors on the study were Mark Hayward, a professor at the University of Texas at Austin, and Yan-Liang Yu, a doctoral student at MSU. The study received funding from the National Institute on Aging and the National Institute of Child Health and Human Development, both part of the National Institutes of Health.
About the American Sociological Association and the Journal of Health and Social Behavior
The American Sociological Association, founded in 1905, is a non-profit membership association dedicated to serving sociologists in their work, advancing sociology as a science and profession, and promoting the contributions to and use of sociology by society. The Journal of Health and Social Behavior is a quarterly, peer-reviewed journal of the ASA.
The research article described above is available by request for members of the media. For a copy of the full study, contact Daniel Fowler, ASA Media Relations Manager, at (202) 527-7885 or firstname.lastname@example.org.
Andy Henion, Media Communications, Michigan State University, wrote this press release. For more information about the study, members of the media can also contact Henion at (517) 355-3294, (517) 281-6949, or email@example.com.