Statins, a group of medications that are widely prescribed to patients with increased levels of blood fats, potentially are related to decreased risk of Alzheimer’s disease. American researchers investigated the influence of gender and ethnicity on this association.
Statins, well-known drugs such as Simvastatin and Atorvastatin, are widely prescribed to treat hyperlipidemia, increased levels of fats (including cholesterol and triglycerides) in blood. Statins are prescribed to 93% of patients who are under treatment for decreasing their blood cholesterol levels.
Due to the fact that Alzheimer’s disease (AD) is related to deposition of a substance named Beta-amyloid, which in turn showed to have a relation with serum cholesterol levels, several research studies were conducted to find if cholesterol-moderating drugs could affect the onset and progression of AD. Researchers from the University of Southern California claimed that those studies showed that using statins were associated with decreased risk of AD; however, they did not have enough sample sizes or methodological precision to produce reliable, generalizable and or gender/ethnicity-specific results. So, they conducted a research study to find any potential relationship between statin use and AD in different sexes and races. They used data from a large sample of Medicare receivers, consist of about 400,000 patients, who were at least 65 years old and received any of the four most commonly prescribed statins: Simvastatin, Atorvastatin, Pravastatin, or Rosuvastatin, from January 2006 to 2008. The patients were categorized based on their statin usage, to one of the low or high-exposure groups and followed-up for occurrence of AD until 2013.
Results showed that the average annual rates of AD diagnoses between 2009 and 2013 in the study sample were 1.72 and 1.32 percent for women and men, respectively. Alzheimer’s disease diagnoses were 10% less frequent among patients who received higher levels of statins between 2006 and 2008 than the patients who had less exposure to statins in the same period of time. Comparing patients with high vs. low exposure to statins showed decreased risks of AD by 15% and 12% among women and men, respectively. The decreased risks of AD were significant for all gender/ethnicity groups except for black men. The reduced risks of AD among gender/ethnicity groups were associated with statin type as well. White, Hispanic and black women, as well as white and Hispanic men, with high exposure to simvastatin had reduced AD risks; while high exposure to atorvastatin was associated with less AD risks among white women, and Hispanic women and men. The reduction of AD risk associated with high exposure to pravastatin and Rosuvastatin was only significant for white women.
To sum up, this study provided useful basic information for clinicians to consider when making a decision on the treatment plan for a patient with hyperlipidemia, based on the patient’s potential benefit regarding decreased risk of AD. However, the results of this study would mostly benefit basic medical science by providing a background to trigger further investigations to shed light on the pathophysiology of AD and the mechanisms by which statins interfere with it.
Written By: Dr. Ali Zargham-Boroujeni