Factor VII antigen levels in a healthy blood donor population.
We determined factor VII antigen (FVIIag) levels in 705 healthy blood donors ranging in age from 17 to 79 years using a two-site solid-phase enzyme immunoassay developed in our laboratory. The mean (+/- SD) FVIIag level for the total population was 102 +/- 31%. FVIIag levels for men (n = 375) and women (n = 330) were 101 +/- 28% and 103 +/- 33%, respectively. A significant increase in FVIIag was observed with age in both men (r = 0.25, p < 0.0001) and women (r = 0.35, p < 0.0001). FVIIag levels were significantly higher in women > 60 years when compared to men (median women: 125%; median men: 111%; p < 0.05). On a subset of the study group (n = 45), FVIIag levels were correlated to total cholesterol (r = 0.27, p = 0.08) and triglyceride (r = 0.41, p < 0.01). Assuming the commonly used reference interval of 60-140% for FVII, the frequencies of FVIIag values for < 60% and > 140% using our assay were 2.1% and 9.2%, respectively. Gender and age-related differences in FVIIag levels must be considered in a reference interval. We further suggest that assay-specific reference ranges be established, which may include values outside the commonly used values of 60-140%.
University of Vermont, Department of Medical Technology, Burlington.
P R
PR
Howard
E G
EG
Bovill
J
J
Pike
W R
WR
Church
R P
RP
Tracy
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000941:Antigens / Q000097:blood*; D001782:Blood Donors; D005167:Factor VII / Q000276:immunology*; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D015203:Reproducibility of Results; D017678:Sex Distribution
D000941:Antigens; D008055:Lipids; D005167:Factor VII