HMG CoA reductase inhibitors have been shown to be effective agents in
lowering cholesterol in patients with primary hypercholesterolaemia.
The aim of this study was to determine whether simvastatin at a low do
se of 5mg given once in the evening was also effective in lowering cho
lesterol. In a multicentre, randomised, placebo-controlled study, 86 s
ubjects (64 males, 22 females) with a mean age of 61+/-13.1 years and
serum total cholesterol concentrations of 5.2 to 7.0 mmol/L were inves
tigated. After an initial 10 weeks of a standard lipid-lowering diet,
the last 4 weeks on placebo. participants were randomised to receive e
ither simvastatin 5mg or matching placebo to be taken in the evening.
After 6 weeks, study participants not achieving a target cholesterol o
f less than or equal to 5.2 mmol/L were titrated to simvastatin 10mg o
r matching placebo for a further 6 weeks. At 6 weeks, 77% of the simva
statin-treated group had achieved a cholesterol level of less than or
equal to 5.2 mmol/L compared with only 5% of the placebo-treated group
(p <0.01). Simvastatin 5mg decreased total cholesterol by 17.7%, low-
density lipoprotein cholesterol by 25.4% and triglyceride by 5.8%; hig
h-density lipoprotein cholesterol rose by 8.7%. Increasing simvastatin
to 10mg in 23% of subjects did not significantly alter the lipid leve
ls. Clinical and biochemical adverse experiences were few and were sim
ilar in the simvastatin and placebo groups. This study demonstrated th
at simvastatin at a low dose of 5mg is a well tolerated and effective
lipid-lowering agent in subjects with mild to moderate hypercholestero
laemia.