Statins, the widely prescribed drugs taken by millions of older men and women to help lower cholesterol levels and ward off heart attacks and strokes, may prevent dementia and memory loss with long-term use. They also do not appear to increase the risk of memory problems in the short term, a new analysis found.
The findings come from an analysis of dozens of rigorous studies that focused on statin use and memory function in more than 23,000 older adults. None had a prior history of thinking or memory problems, and they were followed for up to 25 years.
Some people taking statins have complained of memory problems, saying the drugs were causing their problems. In 2012, the Food and Drug Administration said that a warning about memory problems with short-term statin use must be included on statin drug labels.
But the current analysis found that in the short-term, statins do not impair memory or thinking. In fact, their analysis found that long-term use of the drugs, for more than a year, reduced the risk of dementia by 29 percent. The findings were published in the Mayo Clinic Proceedings.
"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," said Dr. Kristopher Swiger, of Johns Hopkins School of Medicine, one of the study authors. "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."
For the study, the researchers first examined the impact of short-term statin use on memory, attention and problem solving, using the best available evidence. In a follow-up analysis, the authors focused on studies in which participants took statins for longer than a year to see if there was any correlation with a later diagnosis of Alzheimer's disease or other forms dementia. Neither analysis found evidence of memory problems.
The authors note that statins may be protective against dementia because of their beneficial effect on arteries and other blood vessels, including those in the brain. Statins have also been shown to reduce inflammation, which has been increasingly linked to Alzheimer’s disease.
"Vascular dementia is caused by blockages in small blood vessels in the brain that prevent blood flow to certain areas,” said Dr. Seth Martin, the study’s senior author. “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,"
The authors say the analysis results should offer clarity and reassurance to patients and the doctors who prescribe the statin medications.
Source: Swiger KJ, Manalac RJ, Blumenthal RS, Blaha MJ, Martin SS: “Statins and Cognition: A Systematic Review and Meta-Analysis of Short- and Long-Term Cognitive Effects.” Mayo Clinic Proceedings, Sept. 27, 2013.