Correlation of serum HDL-cholesterol and LCAT levels with the fraction of ionized magnesium in children

Correlation of serum lipids and apolipoprotein levels with serum total magn esium concentration and whole blood ionized magnesium level was determined in 47 children (14 female and 33 male; mean age, 8.7 +/- 4.2 years). Mean s erum concentration of magnesium was 2.19 +/- 0.19 mg/dl, whole blood concen tration of ionized magnesium 1.23 +/- 0.08 mg/dl, and fraction of ionized m agnesium (ratio of whole blood ionized magnesium to serum total magnesium) 0.56 +/- 0.04. Neither serum total magnesium level nor whole blood ionized magnesium level had any correlation with serum albumin, lipid, and apolipop rotein levels. However, the fraction of ionized magnesium was significantly correlated with HDL-cholesterol (n = 46, r = 0.31, p = 0.0345), apolipopro tein A-1 (n = 41, r = 0.39, p = 0.0124), and lecithin-cholesterol acyltrans ferase (LCAT) (n = 20, r = 52, p = 0.0184). These results suggest that frac tion of ionized magnesium is more closely linked to serum HDL-cholesterol a nd LCAT level than with the serum total magnesium level or whole blood ioni zed magnesium.