Variability of serum high density lipoprotein cholesterol concentration in healthy subjects in a three year term.

The measurements of serum high density lipoprotein cholesterol (HDL-C), total cholesterol (TC), and triglyceride (TG) were repeated in 170 apparently healthy farming women once a year for three years (1980-2) to examine the variability of the results within the same individual. Although the mean HDL-C and TC values varied to some extent year by year, higher correlation coefficients between any pair and smaller coefficients of variation in the three annual measurements indicated that the within subject variability of HDL-C and TC is much smaller than that of TG. Variation of HDL-C appeared to be associated with lipidaemia. When the effects of age and menopause were eliminated, it was found that non-normolipidaemic people had wider individual variation both in HDL-C and TG. The importance of TG determination for HDL-C evaluation in health examination is emphasised.