Plasma 25-hydroxy-vitamin D in familial hypercholesterolemic children receiving colestipol resin

Abstract

In this study we have assessed effects of Colestipol, a synthetic organic bile sequestrant polymer, on vitamin D metabolism over a year period in children with familial hypercholesterolemia. In the 15 children, mean (±SE) low density lipoprotein (LDL) cholesterol decreased from 221 ± 9 mg/dl (baseline), to 181 ± 7 after 12-14 months of Colestipol resin, P < 0.01. Thereafter, LDL cholesterol remained in the 170-190 mg/dl range. Mean plasma 25-hydroxy- vitamin D (25-OHD) levels appeared to fall slightly and progressively from 32.6 ± 4 ng/ml (baseline) to 29.8 ± 3.5 at 12-14 months, to 25.6 ± 3.3 at 16-18 months, and to 18.5 ± 2.7 at 18-20 months. The decrease in plasma 25-OHD was not significant until 18-20 months (paired t, P < 0.01). After 20 months, plasma 25- OHD levels appeared to increase again and were not significantly different from baseline. Seasonal effects on plasma 25-OHD were not demonstrable. Mean plasma Ca values were mildly increased after Colestipol therapy was begun and were significantly elevated at 18-20 months (10.04 vs. 9.71 mg/dl at baseline). Mean plasma PO4 levels were not significantly different on Colestipol therapy, with the single exception that at 20-22 months plasma P04 was 3.82 vs. 4.05 mg/dl at baseline (P< 0.05). In no subject was serum Ca <9 mg/dl or serum PO4 <2.5 mg/dl at any time during the study. Speculation: In children with familial hypercholesterolemia receiving bile acid sequestrants (10-15 g/day), consistent changes in Ca, PO4 < and 25-OHD levels appear to be unlikely, but long term monitoring of these factors would be important in regard to optimal growth and development. © 1978 International Pediatric Research Foundation, Inc.