Lymphocyte cell counts in middle age are positively associated with subsequent all-cause and cardiovascular mortality.
BACKGROUND
There is an association between higher white blood cell counts and all-cause and cardiovascular disease (CVD) mortality. However, little is known about the prognostic significance of circulating lymphocyte and lymphocyte subset numbers.


OBJECTIVE
The present study examined the association between T-, CD4-, CD8- and B-cell numbers, and the CD4:CD8 ratio, and all-cause and CVD mortality.


METHODS
Lymphocyte and lymphocyte subset numbers were measured by flow cytometry in a cohort of 4256 male middle-aged Vietnam-era US veterans. Mortality was tracked for 15 years and cause of death was determined from death certificates.


RESULTS
In fully adjusted survival analyses, high circulating T-cells numbers were associated with increased risk of both all-cause [hazard ratio (HR)=1.75, 95% confidence interval (CI) 1.15-2.66] and cardiovascular (HR=3.57, 95% CI 1.53-8.33) mortality. The former association appeared to reflect an effect for high CD8-cells numbers, the latter an effect for high CD4-cell numbers. For all-cause mortality, a high CD4:CD8 ratio was protective (HR=0.58, 95% CI 0.41-0.81). Cardiovascular mortality was also predicted by high B-cells numbers (HR=1.87, 95% CI 1.10-3.17).


CONCLUSIONS
Circulating lymphocyte and lymphocyte subset numbers may have substantial prognostic significance for both all-cause and CVD mortality.
School of Sport and Exercise Sciences, University of Birmingham, Birmingham B15 2TT, UK. a.c.phillips@bham.ac.uk
A C
AC
Phillips
D
D
Carroll
C R
CR
Gale
M
M
Drayson
G D
GD
Batty
D000328:Adult; D016175:B-Lymphocyte Subsets; D002318:Cardiovascular Diseases / Q000097:blood / Q000401:mortality*; D002423:Cause of Death; D015331:Cohort Studies; D005434:Flow Cytometry; D006801:Humans; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011446:Prospective Studies; D016019:Survival Analysis; D016176:T-Lymphocyte Subsets; D014728:Veterans; D058014:Veterans Health / Q000706:statistics & numerical data*