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Researchers say Black women with heart health issues in midlife have a higher risk of cognitive decline. Maskot/Getty Images
  • Black women with heart health issues may experience earlier cognitive decline, according to a new study.
  • The research was conducted over a 20-year peroid with cognitive assessments completed every one to two years throughout an almost ten-year follow-up period.
  • Researchers reported that processing speed declined in Black women during midlife compared to white women but working memory did not decline in either group.

Black women with poor cardiovascular health might have an elevated risk of early cognitive decline, according to a new study published in the Journal of the American Heart Association.

Researchers examined the cognition and working memory of 765 women enrolled in the Chicago site of the Study of Women’s Health Across the Nation (SWAN).

The participants included 363 Black and 402 white women between the ages of 42 and 52. None of the women had cardiovascular disease.

Cognition and working memory assessments were conducted annually or biennially over a maximum of 20 years, with an average follow-up of nearly 10 years.

The researchers measured cardiovascular health based on the American Heart Association’s Life’s Essential 8 checklist. The eight categories are blood pressure, body mass index, glucose, cholesterol, smoking, physical activity, diet, and sleep.

“A large body of research supports the relationship between cardiovascular health and cognitive functioning,” said Dr. José Morales, a vascular neurologist and neurointerventional surgeon at the Pacific Neuroscience Institute in California who was not involved in the research. “The results of this study lend further support to this relationship and the urgent need to address these risk factors early.”

“While the study attempted to control for differences in baseline demographic data, drawing conclusions from phenotypic racial differences misses a myriad of factors that can lead to misinterpretation,” Morales told Medical News Today. “Race as a factor for these differences has previously been shown but is difficult to interpret using the measurements included in this study alone.”

The researchers were interested in whether better cardiovascular health was related to less cognitive decline equally in Black and white women in their midlife.

Their findings included:

  • Processing speed appeared to decline in Black women with lower heart health but did not do so for white women.
  • Working memory did not decline in either Black or white women with lower heart health.

Working memory refers to the small amount of information that can be held that is easily accessed in cognitive tasks, according to the National Institutes of Health. It is a short-term storage of information that could be needed when problem-solving or reasoning.

“Although Black women declined faster in processing speed than white women on average, there was heterogeneity within the Black subgroup,” Imke Janssen, PhD, a professor at Rush University Medical Center in Chicago and an author of the study, told Medical News Today. “Those with lower [cardiovascular health] declined faster than those with higher [cardiovascular health].”

“To study the biological plausibility of this finding, we analyzed components of the global [cardiovascular health] score and found that blood pressure and smoking were the main drivers of this heterogeneity within the Black subgroup,” Janssen continued. “The subgroup of Black women with low cardiovascular health had a significantly higher rate of hypertension (77.8% for Black women versus 41.6% for white women). Black Americans have greater exposure to the adverse effects of elevated blood pressure, with an earlier onset of about five years before their white counterparts, and have lower hypertension control.”

“Moreover, Black Americans have a greater exposure to the adverse effects of nicotine, a higher exposure to second-hand smoke, and a greater use of menthol cigarettes that mask the harshness of tobacco smoke and make it harder to quit,” Janssen noted.

According to the Centers for Disease Control and Prevention (CDC), tobacco use interferes with achieving equity in healthcare between races.

“Serum cotinine, a marker of nicotine, is higher in Black individuals than in white individuals, possibly because of their lower cessation rates. It has been associated with worse cognitive functioning, including processing speed,” Janssen explained.

“Our data show that optimization of cardiovascular health in midlife Black women could slow cognitive aging, maximize independence, and reduce racial inequality in dementia risk,” Janssen said.

She also pointed out that a clinical study is needed to determine if improvements in cardiovascular health would improve cognitive health.

Morales agrees that additional studies are needed to better understand the differences in working memory between the two groups.

“Working memory assessments may be confounded by practice effects as the authors allude to and their attempts to control for this may have not been robust enough given the statistically significant decline evident with processing speed, which is closely related neuroanatomically to the networks that underlie working memory,” he said. “Future studies that can more robustly measure differences in working memory with serial assessments without the practice effect confounder will be needed to determine if the findings from this study are reproducible. “