Treating patients more intensively with statins can lead to even greater reductions in the risk of heart attacks, revascularisation and ischemic stroke, according to a report in The Lancet.
The benefit achieved is directly proportional to the reduction in low-density lipoprotein (LDL) cholesterol. With each 1.0 mmol/L reduction there is a decrease in the annual rate of events by just over a fifth.
"It is a continuous relationship right the way down to very low levels of LDL cholesterol," said Dr. Colin Baigent of Oxford University, Britain, who led the study with other colleagues from University of Sydney, Australia.
In a commentary, Dr Bernard Cheung and Dr Karen Lam of the University of Hong Kong, who weren't involved in the research, say, "at the population level, statins are underused."
People who benefit from statin therapy the most
"The urgent priority is to identify people who would benefit most from statin therapy and to lower their LDL cholesterol aggressively, with the more potent statins if necessary," they write.
Dr Baigent and colleagues from the Cholesterol Treatment Trialists' (CTT) Collaboration conducted a meta-analysis of 26 statin trials that covered 170,000 people.
Of these, five trials compared intensive statin treatment with regular statin treatment, and the other 21 studies compared the effects of taking statins versus not taking statins.
When analysing the combined results of the five intensive trials, the researchers found that compared with less intensive treatment, more intensive treatment produced a "highly significant" 15% further drop in major vascular events.
Effects of the treatment
This included a 13% cut in heart-related death or non-fatal heart attack, a 19% cut in coronary revascularisation, and a 16% reduction in strokes.
Taking all 26 trials together, all-cause mortality was reduced by 10% for every 1.0 mmol/L reduction in LDL cholesterol, reflecting declines of 20% in deaths due to coronary heart disease and 11% in other cardiac-related deaths, the researchers say.
There were no significant effects on deaths due to stroke or other vascular causes, or on deaths due to cancer or other non-vascular causes, and there was also no evidence of any excess risk of cancer - a risk some researchers had previously suggested could be linked with taking LDL cholesterol down to very low levels.
Dr Jeremy Pearson of the British Heart Foundation, which partly funded the study, said its findings may change the way doctors are advised to prescribe statins, and would give them "another tool for helping people keep their hearts healthy."
Many statin brands such as Merck & Co's Zocor are now generic, and many more will soon go off patent, making the drugs even more affordable.
(Reuters Health, Kate Kelland, November 2010)