High levels of the atherosclerosis marker coronary artery calcium (CAC) may be a good predictor of mortality and coronary heart disease (CHD) risk as well as myocardial infarction in individuals aged 80 and older without cardiovascular disease (CVD), according to a US-based observational study.
Researchers looked at 532 participants to determine whether CAC levels correlated with death, dementia and CHD among the elderly. CAC was defined as deposits that can narrow arteries and increase heart attack risk.
Of the total number of participants, 36 percent had CAC scores that were greater than the highest level (>400). Women and African-Americans showed lower CAC scores than men. CAC score and number of coronary calcifications directly correlated to age-adjusted total mortality and CHD. Age-specific incidence of dementia was higher than of CHD.
About 25 percent of deaths were attributed to CHD and 16 percent to dementia. Of the total deaths reported, 64 percent were of individuals with prior diagnosis of dementia. White women with low CAC scores had a significantly decreased incidence of dementia.
The findings suggest that the prevalence of dementia in older populations will likely increase as prevention and treatment of CHD improve and increase the longevity of the general population. A zero or very low CAC score could be associated with a low risk of dementia and cardiovascular risk factors such as high blood pressure, diabetes, smoking and sedentary behaviour leading to the development of atherosclerosis and eventually CHD could also affect progression of brain pathology, such as dementia risk.
The study highlights that people who reach older ages can expect a significant increase in the risk of dementia, although the small sample size necessitates replication of the results in other studies of the elderly.