Statins ‘may reduce dementia risk’
Tuesday 1st October 2013, 4:00PM BST.
Cholesterol-lowering statin drugs pose no threat to short-term memory and may protect against dementia if used over a long period, according to a review of research evidence.
Scientists who pooled data from 16 robust studies found that taking statins for more than a year cut the risk of dementia by 29%.
Questions about the drugs’ effects on the brain last year led the US Food and Drug Administration to order new medicine labels warning of possible memory problems linked to statins.
But the new findings suggest such fears are not justified, and statins may actually help to safeguard the brain.
Dr Kristopher Swiger, from Johns Hopkins Medicine in Baltimore, US, said: “All medications, including statins, may cause side effects, and many patients take multiple medicines that could theoretically interact with each other and cause cognitive problems.
“However, our systematic review and meta-analysis of existing data found no connection between short-term statin use and memory loss or other types of cognitive dysfunction. In fact, longer-term statin use was associated with protection from dementia.”
The researchers conducted two different analyses. One looked at the impact of short term statin use on brain function, while the other examined how taking the drugs long term related to Alzheimer’s disease or vascular dementia.
The findings are published online in the journal Mayo Clinic Proceedings.
Co-author Dr Raoul Manalac, also from Johns Hopkins Medicine, said: “Our goal was to provide clarity on this issue based on the best available evidence.
“We looked at high-quality, randomised controlled trials and prospective studies that included more than 23,000 men and women with no prior history of cognitive problems. The participants in those studies were followed for up to 25 years.”
Statins lower levels of “bad” cholesterol, or low-density lipoprotein (LDL) in the blood.
LDL contributes to the build up of plaque deposits that narrow blood vessels in the brain as well as the heart.
The drugs have been shown to reduce inflammation within blood vessels and the risk of stroke-inducing blood clots.
Dr Seth Martin, another member of the Johns Hopkins team, said: ” Because of their effect on arteries to reduce or stabilise plaque, and prevent strokes, it makes sense that statins could be protective in the brain against dementia.
” Vascular dementia is caused by blockages in small blood vessels in the brain that prevent blood flow to certain areas. Medications such as statins that reduce plaque and inflammation in coronary arteries may also be having the same effect on blood vessels in the brain.”
Professor Roger Blumenthal, director of the Johns Hopkins Ciccarone Centre for the Prevention of Heart Disease, said: “Statins can be life-saving medications for high-risk individuals, but many of our patients became concerned about taking the drugs after the FDA created labelling changes last year. This very robust analysis of the best data available should allay those concerns.”
Dr Simon Ridley, from charity Alzheimer’s Research UK, said: ” This type of analysis is a very useful way of pulling together the best available evidence on a topic, but it’s still not possible to conclusively know from this review whether statins could prevent dementia.
“Although research has shown that controlling cholesterol levels may lower the risk of dementia, large clinical trials have so far been unable to show that statins can prevent the condition. Anyone who is worried about their memory, or wants to know whether they should be taking statins, should talk to their doctor.
“There is currently no certain way to prevent dementia, and it’s vital to continue investing in research to find much-needed preventions for the condition. In the meantime, the best evidence suggests that the risk of the condition can be reduced by eating a healthy, balanced diet, exercising regularly, keeping blood pressure in check, and not smoking.”