Apolipoprotein B and A-I values in 147576 Swedish males and females, standardized according to the World Health Organization-International Federation of Clinical Chemistry First International Reference Materials.

Serum concentrations of apolipoprotein (apo) B and apo A-I were measured from 1985-1996 in a Swedish population sample of 83 112 males and 64 464 females, ages <20 to >80 years, using an automated immunoturbidimetric method calibrated against fresh pools of human serum and commercial calibrators. All values were recalculated in 1997 after calibration against the WHO-IFCC First International Reference Materials. The recalculation factor was 1.059 for apo B, whereas for apo A-I, the correction was: y = 0.989x + 0.101. The total CVs for both apo B and A-I were generally <7%. The mean value (+/- SD) for apo B was 1.31 +/- 0.35 g/L in all males and 1.22 +/- 0.36 g/L in all females. The mean apo A-I concentration was 1.36 +/- 0.22 g/L in males-10% lower than in females (1.51 +/- 0.24 g/L). The mean value of apo B increased up to 60 years of age in males and up to 70 years of age in females. apo A-I concentrations changed only slightly with age in both males and females. apo A-I concentrations among Swedes are nearly identical to those reported recently by two American studies and those obtained in a Finnish population sample. Mean apo B concentrations differ somewhat between the populations but mirror-as expected-differences in total cholesterol concentrations. The highest values were noted in Swedish subjects. The Swedish sample population is, to our knowledge, the largest describing the distribution of apo B and A-I in a general population of adult males and females of all ages determined with procedures standardized and traceable to the WHO-IFCC First International Reference Materials.