Effects of lovastatin and pravastatin on sleep efficiency and sleep stages

The effects on sleep of two 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (40 mg lovastatin and 40 mg pravastatin) were evaluated in 12 normal subjects in a double-blind placebo-controlled sleep laboratory study. Subjects were randomly assigned to each of two parallel groups (lovastatin and pravastatin). Each parallel-group protocol consisted of 22 consecutive nights including 4 placebo-baseline nights, 2 weeks of drug administration, and 4 placebo-withdrawal nights. Lovastatin did not disturb sleep initially (nights 5 through 7) but, with continued administration (nights 16 through 18), it significantly and markedly increased wake time after sleep onset and stage 1 sleep compared with baseline. By contrast, pravastatin was not associated with sleep disturbance either initially or with continued use. Neither drug caused any sleep disturbance after withdrawal. Lovastatin's sleep disturbing effects with continued administration are attributed to its high degree of lipophilicity in contrast with the hydrophilicity of pravastatin.