[Monitoring plasma levels of vitamin D metabolites in simvastatin (Zocor) therapy in patients with familial hypercholesterolemia].

BACKGROUND: Simvastatin is a hypolipidaemic agent, a statin which inhibits cellular cholesterol synthesis by blocking 3HMG CoA reductase. The authors present a report on levels of plasma metabolites of vitamin D after treatment with 10 and 20 mg simvastatin daily in 13 patients, heterozygotes with hypercholesterolaemia during a five-week period. METHODS AND
RESULTS: During simvastatin treatment in all patients plasma levels, of the sum of hydroxylated vitamin D metabolites and 1,25-dihydroxyvitamin D after five weeks of treatment with 10 and 20 mg hypolipidaemic drug were examined. For assessment of vitamin D metabolites radioassay was used which assesses the sum of hydroxylated vitamin D metabolites, and radioimmunoanalysis for assessing the 1,25-dihydroxyvitamin D plasma level. For statistical evaluation the non-parametric Friedman test and simultaneous testing was used.
CONCLUSIONS: Simvastatin raises the plasma levels of the sum of hydroxylated vitamin D metabolites and 1,25-dihydroxyvitamin D in a dose-dependent ratio. The authors recommend to monitor the plasma levels of vitamin D metabolites over a longer time period.