Lymphocyte sub-population cell counts are associated with the metabolic syndrome and its components in the Vietnam Experience Study.

OBJECTIVE The metabolic syndrome (MetS) increases the risk of cardiovascular disease morbidity and mortality. MetS is also associated with increases in the number of circulating white blood cells. Lymphocyte sub-population counts have also been implicated in cardiovascular disease; this analysis will examine whether or not they are associated with MetS. METHODS Participants were 4255 Vietnam-era US veterans. From military service files, telephone interviews, and a medical examination, occupational, socio-demographic, and health data were collected. MetS was ascertained from: body mass index; fasting blood glucose or a diabetes medication; blood pressure or a diagnosis of hypertension; HDL cholesterol; and triglyceride levels. Circulating T, T4, T8 and B lymphocytes cell numbers were determined by flow cytometry. RESULTS In fully adjusted logistic regression analyses, high lymphocyte sub-population counts were associated with an increased risk of MetS: T cells, OR=2.68, 95%CI 1.99-3.61, p<.001; T4 cells, OR=2.37, 95%CI 1.78-3.15, p<.001; T8 cells, OR=1.79, 95%CI 1.43-2.24, p<.001; B cells, OR=1.82, 95%CI 1.51-2.19, p<.001. High lymphocyte sub-population numbers were also associated with an increased likelihood of possessing each of the MetS components, as well as the number of components possessed. CONCLUSIONS These results extend previous research which has largely been confined to total white blood cell or overall lymphocyte counts. If the present associations arise in prospective research, it is possible that simple lymphocyte cell counts could provide an additional prognostic indicator of risk for MetS.