T-Helper type 1 bias in healthy people is associated with cytomegalovirus serology and atherosclerosis: the multi-ethnic study of atherosclerosis

Background--although t-helper type 1 (th1) cells are considered important in atherosclerosis,the relationships between th1 and th2 cells and atherosclerosis have not been examined in population-based studies. methods and results--we measured th cells as a percentage of lymphocytes by flow cytometry using cd4 staining (%cd4) in 917 participants of the multi-ethnic study of atherosclerosis. we also measured interferon gamma-positive and interleukin-4-positive cd4+ cells,representing th1 and th2 subpopulations (%th1 and %th2),respectively. we found that %cd4 was 1.5% lower per 10 years of age (p<0.0001). whites had higher %cd4 and lower %th1 and %th2 values than other race/ethnic groups. body mass index (bmi) and blood pressure were associated with %cd4,but no traditional cardiovascular disease (cvd) risk factors were associated with %th1 or %th2. in multivariable models,the major independent variable associated with %th1 was cytomegalovirus (cmv) antibody titer,with minor contributions from age,sex,seasonality,and interleukin-6. in models with coronary artery calcification level as the outcome,significant independent variables included age,sex,smoking status,and %th1 (β=0.25; p≤0.01). both %th1 and %th2 were associated with common carotid intimal media thickness (β=0.02 and 0.02,respectively; both p<0.05),as were age,sex,race/ethnicity,blood pressure,and bmi. conclusions--th1 bias is associated with subclinical atherosclerosis in a multiethnic population. the main th1 correlate was cmv infectious burden. these findings are consistent with a role of th1 cells in atherosclerosis and suggest the importance of prospective studies of t-helper cell biasing in cvd. © 2013 the authors.