May 13, 2009 – Next-generation statins ineffective in preventing or slowing Alzheimer’s disease, according to analysis1 two large studies involving 26,000 people. But a first-generation statin – now available in generic form – would show promise.
Marketed to lower blood cholesterol levels in patients with high cholesterol, statins form a family of drugs tested to treat or prevent other symptoms or diseases, such as Alzheimer’s disease.
However, the analysis of two American studies started in 2002 – PROSPER and HPS – indicates that the use of two new kinds of statins does not make it possible to prevent the occurrence of Alzheimer’s disease or to stop it.
The potential of “old generation” statins
But these results do not despair Judes Poirier2, specialist in Alzheimer’s disease, who still believes in the potential of certain statins to prevent this disease which attacks memory.
“This analysis relates to two studies completed in 2005. But recent studies have been carried out since, including one by the American government on 700,000 veterans”, explains Judes Poirier, who is also director of the molecular neurobiology unit of the Douglas Institute Research Center.
The present study is a so-called “prospective” one, that is to say that it was not based on any starting hypothesis. The goal was to compare people’s health over the years, depending on the type of statins they were taking.
“No protective effects were seen with recent statins, but the risk of developing Alzheimer’s disease was 54% lower in people who took simvastatin – an ‘old generation’ statin,” available in generic form (Zocor©) for nearly three years, ”says Judes Poirier.
This discovery, however, debunks the hypothesis that cholesterol plays some role in the onset of the disease.
“If the cholesterol hypothesis had been correct, all statins would have made it possible to prevent Alzheimer’s disease, since all the participants on statins saw their cholesterol level decrease”, he notes.
The effectiveness of Zocor lies in its ability to enter the brain, which other statins do not. But we do not yet understand the mechanism by which Zocor manages to prevent Alzheimer’s disease.
For people at risk
According to Judes Poirier, there is no point in running to your doctor to be prescribed Zocor, if there is a fear of one day suffering from Alzheimer’s disease: other clinical trials must confirm the results obtained in the context of of the study of veterans.
However, the latter showed that simvastatin was effective in people most at risk of suffering from this disease, that is to say when there has already been one or more cases in their family. These people at risk carry a marker gene called “APOe”.
“We know that the disease occurs on average three years after we have discovered the APOe gene, in 80% of carriers,” says Judes Poirier. We can therefore think that taking Zocor five years before the appearance of these markers could become a means of prevention against Alzheimer’s disease. “
Martin LaSalle – PasseportSanté.net
1. McGuiness B, Craig D, et al, Statins for the prevention of dementia, Cochrane Database of Systematic Reviews, April 15, 2009, no 2.
2. See our interview with Judes Poirier Alzheimer’s disease: the new epidemic.