SERUM UBIQUINONE CONCENTRATIONS AFTER SHORT-TERM AND LONG-TERM TREATMENT WITH HMG-COA REDUCTASE INHIBITORS

Serum ubiquinone levels were studied during long- and short-term treat ment with 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors in 17 men with primary non-familial hypercholesterolaemia. The serum u biquinone levels were determined after the patients had received simva statin (20-40 mg per day) for 4.7 years, after a 4 week treatment paus e and again after they had resumed treatment with lovastatin (20-40 mg per day) for 12 weeks. During the treatment pause the average serum u biquinone levels increased by 32 %; resumption of treatment caused a r eduction of 25 %. The changes in the levels of ubiquinone and serum to tal cholesterol as well as those of ubiquinone and low-density lipopro tein cholesterol were closely parallel. This suggested that changes in serum ubiquinone reflected changes in cholesterol-containing serum li poproteins which could serve as carrier vehicles for ubiquinone. After long-term simvastatin treatment and after shortterm lovastatin treatm ent, average serum ubiquinone levels (1.16 and 1.22 mg.l(-1), respecti vely) were similar to that observed in a group of apparently healthy m iddle-aged men (1.16 mg.l(-1)).