Friday, November 09, 2007
simvastatine en slaapproblemen
Noncardiac Effects of Statins
The current study, called the University of California, San Diego (UCSD) Statin Study, was a double-blind, randomized, placebo-controlled trial evaluating noncardiac effects of statins. A total of 1016 men older than 20 years and postmenopausal women were enrolled if they had low-density lipoprotein (LDL)-cholesterol levels between 115 and 190 mg/dL, no known cardiovascular disease or diabetes, and fasting blood glucose of below 140 mg/dL. At the time the study began, statin therapy was considered optional for these subjects.
They were randomized to receive 40 mg of pravastatin, 20 mg of simvastatin (considered pharmacologically equivalent), or placebo, and followed up for 6 months. Sleep was a prespecified secondary endpoint of this trial.
Sleep was assessed by the adapted Leeds Sleep Scale, rating sleep quality on a scale of 0 to 30, and a sleep-problems scale, where patients rated their general experience of sleep problems without defining the nature of the problems, on a scale of 0 to 10 at baseline, and then rated them from "much better" to "much worse" on a 5-point scale.
At baseline, the 3 randomized groups were equivalent in terms of their sleep quality and sleep problems. On follow-up, however, "the simvastatin group reported significant worsening relative both to the placebo group and the pravastatin group in both the sleep-quality outcome and the sleep-problem outcome," Dr. Golomb said. Pravastatin did not differ significantly from placebo on either of these measures.
Their study is limited to some degree by including only 1 lipophilic and 1 hydrophilic statin, the relatively low doses used at the time the study was begun, and the lack of assessment of a dose response. It's also not clear if these effects would be different in the groups that were excluded from the study, she noted.
The mechanism of this difference is also unclear, she said. It may relate to the lipophilicity of simvastatin vs hydrophilicity of pravastatin, the difference in cholesterol lowering, which was greater with simvastatin, or some other unknown factors.
What is clear is the importance of sleep to good health, function (including memory and cognition), mood, well-being and safety, Dr. Golomb concluded, "so the importance in terms of potential ramifications to health of sleep problems is quite large."
