CHICAGO --- Higher levels of education are associated with a lower prevalence of coronary artery calcium, an indicator of low-grade or asymptomatic atherosclerosis (thickening and plaque deposits in the artery walls) among young adults and those in early middle age, according to a study in the April 19 issue of JAMA.
Lijing L. Yan, research assistant professor of preventive medicine at Northwestern University Feinberg School of Medicine and Guanghua School of Management, Peking University, Beijing, was first author on the study.
Many studies have documented that education is inversely associated with a wide array of clinical disease outcomes and death, and the relationship between education and cardiovascular disease and coronary heart disease in particular is among the most consistent and pronounced. But little is known about the relationship between education and subclinical disease (an illness that stays below the surface of clinical detection).
Yan and colleagues analyzed data from the Coronary Artery Risk Development in Young Adults (CARDIA) study, which included 2,913 participants (45 percent black; 54 percent women). The participants, who were 18 to 30 years old at the beginning of the study in 1985-1986, were recruited from Chicago, Minneapolis, Birmingham, Ala., and Oakland, Calif.
There were 128 study participants with less than a high school diploma; 498 were high school graduates; 902 had some college; 764 were college graduates; and 621 had more than a college education.
At year 15 of the study, the overall prevalence of coronary artery calcium (CAC) among eligible participants was a little over 9 percent.
“For the biracial young adult and early middle-aged cohort (aged 33 to 45 years) with a wide spectrum of educational levels, educational level was inversely associated with prevalence of CAC in a graded dose-response fashion, with particularly higher prevalence for individuals with less than a high school degree,” the authors reported.
The prevalence of CAC was four times higher among study participants with less than a high school degree, compared with those who had more than a college education.
These findings are partially explained by risk factors assessed 15 years before the measurement of CAC and by increase in these risk factors over time.
The risk factors include blood pressure, cholesterol, waist circumference, smoking and physical activity. The authors suggest that pathways and mechanisms linking education and subclinical disease remain to be further explored.
“Fundamental changes in preventive measures very early in life are required to address social and economic disparities in health. In addition, integrated prevention and intervention strategies effective for less educated persons are also needed,” Yan and colleagues concluded.
Collaborating with Yan on the study were Kiang Liu, professor of preventive medicine; Martha L. Daviglus, M.D., associate professor of preventive medicine; Laura A. Colangelo; Catarina I. Kiefe, M.D.; Stephen Sidney; M.D.; Karen A. Matthews; and Philip Greenland, M.D., Harry W. Dingman Professor of Cardiology and executive associate dean for clinical and translational research, Feinberg School.
This study was funded by grants from the National Heart, Lung, and Blood Institute, National Institutes of Health.