Background and objectives : The prevalence of cardiovascular diseases in middle age and risk factors is higher in men than in women. Associations between midlife cardiovascular conditions or risk factors and midlife cognitive decline have been reported, but few studies have evaluated sex differences in these associations. Methods: We included 1,857 participants enrolled in the population-based Mayo Clinic Study of Aging who were between 50 and 69 years old at the start of the study. Participants were evaluated every 15 months by a coordinator, neurological evaluation and neuropsychological tests. Neuropsychological testing used nine tests to calculate global and domain-specific cognitive z-scores (memory, language, executive function, and visuospatial skills). Extractor nurses reviewed participants’ medical records to determine the presence of cardiovascular conditions (coronary heart disease, arrhythmias, congestive heart failure) and risk factors (hypertension, diabetes, dyslipidemia, obesity, smoking). Linear mixed-effects models assessed the association between baseline cardiovascular conditions or risk factors and global and domain-specific cognitive impairment. Multivariable models adjusted for demographics, APOE genotype, depression, and other medical conditions. Interactions between sex and each cardiovascular condition or risk factor were examined, and results were stratified by sex. Results: Overall, 1,465 (70.3%) participants had at least one cardiovascular condition or risk factor; the proportion of men was higher than that of women (767 (83.4%) vs 698 (74.5%), p <0.0001). Cross-sectionally, coronary heart disease and smoking were associated with lower visuospatial z-score in multivariable models. Longitudinally, several cardiovascular conditions and risk factors were associated with decreases in global and/or domain-specific z scores, but not visuospatial z scores. Most cardiovascular conditions were more strongly associated with cognition among women: coronary heart disease and other cardiovascular conditions were associated with decreased global cognition only in women (all p < 0.05). Additionally, diabetes, dyslipidemia, and coronary heart disease were associated with decreased language z-score only in women (all p < 0.05). However, congestive heart failure was associated with decreased language z-score only in men (all p < 0.05). Conclusions: Midlife cardiovascular conditions and risk factors are associated with midlife cognitive decline. Furthermore, specific cardiovascular conditions and risk factors have stronger associations with cognitive decline in midlife for women than for men despite the higher prevalence of those conditions in men. |
Comments
A Mayo Clinic study shows that heart conditions such as coronary artery disease and cardiovascular risk factors such as diabetes and high cholesterol have a stronger association with declining memory and thinking skills during middle age in women than in men. That’s despite a higher prevalence of those conditions in men. The research is published in Neurology , the medical journal of the American Academy of Neurology.
"It is well known that men, compared to women, have a higher prevalence of cardiovascular conditions and risk factors in midlife. However, our study suggests that women in midlife with these conditions and risk factors have a higher risk of cognitive decline. says Michelle Mielke, Ph.D., an epidemiologist and neuroscientist at Mayo Clinic, and lead author of the study. "Therefore, while all men and women should be treated for cardiovascular conditions and risk factors in midlife, additional monitoring of women may be needed as a potential means of preventing cognitive decline."
The research used the population-based Mayo Clinic Study of Aging and included 1,857 participants without dementia who were between 50 and 69 years old at their baseline visit. Of the participants, 920 were men and 937 were women. Every 15 months for an average of three years, study participants’ global cognition was assessed with nine tests of memory, language, executive function, and spatial skills.
Information on cardiovascular status and risk factors was obtained through the population-based Rochester Epidemiology Project. The conditions included coronary artery disease, heart rhythm disorders, congestive heart failure, peripheral artery disease and stroke.
Risk factors included high blood pressure, diabetes, high cholesterol, smoking and obesity. About 79% of the participants, or 1,465, had at least one cardiovascular risk factor or condition: 83% of men, compared to 75% of women.
The study found that most cardiovascular conditions were more strongly associated with cognitive function among women. The annual decline in global cognition associated with coronary artery disease, for example, was more than twice as large for women as for men.
Additionally, diabetes, high cholesterol, and coronary artery disease were associated with greater language impairment in women. However, congestive heart failure was associated with greater language impairment in men.
Understanding sex differences in the development of cognitive decline is important to improving the health of women and men, says Dr. Mielke. Middle-aged adults, especially women with a history of heart disease, may represent critical subgroups for early monitoring.
More research is needed across the lifespan to examine potential mechanisms that explain sex differences in the relationship between cardiovascular factors and cognition, such as hormones, genetics, lifestyle, and psychosocial factors, says Dr. .Mielke.
Funding for this study was provided by grants from the National Institutes of Health and the GHR Foundation, and resources were provided by the Rochester Epidemiology Project, which is supported by the National Institute on Aging.
Other authors of the study are Nan Huo, M.D., Ph.D.; Prashanthi Vemuri, Ph.D.; Jonathan Graff-Radford, MD.; Jeremy Syrjanen; Mary Machulda, Ph.D.; David Knopman, M.D.; Clifford Jack Jr., MD; and Ronald Petersen, M.D., Ph.D. - the entire Mayo Clinic.
Dr. Mielke is a consultant for Biogen and Brain Protection Co., and serves on the editorial boards of Neurology and Alzheimer’s & Dementia Journal.
