Statins Lower Risk for Alzheimer’s Disease

• Data from Medicare claims were analyzed in a new study to identify the association between high exposure to statins and Alzheimer’s disease (AD) risk.
• 15% reduction of Alzheimer’s disease risk in women and 12% reduction in AD in men was identified on high exposure to statins.
• The extent of risk reduction depended on the type of statin used and the ethnicity of the patient.

An increased use of statins meant to lower cholesterol could lower the risk for Alzheimer’s disease, on analysis of Medicare data. The decrease in risk for Alzheimer’s disease is associated with the type of statin that is used and the race /ethnicity of the patient. Previous studies have shown that elevated level of cholesterol in the body increases the risk for Alzheimer’s disease. Therefore, there has been increased focus on lipid lowering drugs or statins, which could act as preventive or therapeutic agents.

Dr. Julie M. Zissimopoulos and colleagues from the University of Southern California, Los Angeles, studied Medicare claims of 400,000 who reported to have been diagnosed with Alzheimer’s disease and examined the role of statins in their diagnosis.

The researchers studied the effect of high exposure and low exposure to the following four statins:

• Simvastatin
• Atorvastatin
• Pravastatin
• Rosuvastatin

Race and the Risk of Alzheimer’s Disease

The researchers found that between the years 2009 to 2013, 1.72% of women and 1.32% of men were diagnosed with Alzheimer’s disease. It was found that Caucasian men had the lowest incidence with 1.32%, indicating that race played a role in determining the risk for Alzheimer’s disease.

The study also found that the average use of statin per day was found to be lower among the African-American and the Hispanic population. The lowered use of statin among this population could also be the reason for the higher incidence of the disease, while a higher use of statins among the Caucasian population could have contributed to the lower incidence.

High Exposure to Statins and Alzheimer’s Disease Risk

Advertisement

High exposure to statins showed a 15% decrease in Alzheimer’s disease (AD) risk in women and 12% decrease among men, with a variation based on race/ ethnicity.

Statin Drug	Mode of Action
Simvastatin	Lowered risk of AD in White, Hispanic and Black women, Lowered risk of AD among White and Hispanic men.
Atorvastatin	Lowered risk of AD in White, Hispanic and Black women. Lowered risk of AD among Hispanic men.
Pravastatin and Rosuvastatin	Lowered risk of AD in White women.

There was no association that was detected between high exposure to statin use and lowered Alzheimer’s disease risk in the African-American men.

Advertisement

The authors of the study concluded by saying "This suggests that certain patients, facing multiple, otherwise equal statin alternatives for hyperlipidemia treatment, may reduce AD risk by using a particular statin. The right statin type for the right person at the right time may provide a relatively inexpensive means to less the burden of AD”

Alzheimer’s Disease:

Alzheimer’s disease is a neurodegenerative disease that usually affects people over 65 years of age, however, there are also incidences of early onset Alzheimer’s disease. This condition is characterized by loss in memory and the failure to complete simple chores and tasks. There is a lot of attention that is provided to this disease due to the increased dependency which can affect the quality of life of a senior citizen.

The study on the effect of statins and lowered risk of Alzheimer’s disease should bring into focus the following important criteria:

• The Blood Brain Barrier: The blood brain barrier is the delicate network of cells that separate the circulatory system from the brain. It provides the necessary nutrients to the brain but prevents the entry of chemicals into the brain. Therefore the permeability of these statins into the brain should be studied to understand the effect of these statins in the brain. Recently, scientists developed a model of the blood brain barrier on a microchip to study permeability of drugs.
• The Type of Cholesterol That Should Be Lowered: High cholesterol levels have been found to increase the risk for Alzheimer’s disease. Further studies are required to understand the type of cholesterol that needs to be lowered, whether high density lipoprotein (HDL) or low density lipoprotein (LDL).
• The Stage of AD: The statin trials should be conducted at various stages of Alzheimer’s disease to understand the stage of maximum benefit.

Statins are also found to lead to a large number of effects that could influence the risk for Alzheimer’s disease. Statins are found to affect genes that are associated with cell signaling, trafficking and apoptosis. Simvastatin is found to affect 38 genes and pravastatin 21 genes.

The current study was based on data collected as part of Medicare, based on claim requests from patients. It is a good foundation to ascertain a link, but the exact association should be detailed further by using clinical trials. This will help in establishing a causal relationship.

Identifying the effect of statins in decreasing cholesterol and in lowering Alzheimer’s disease risk in early stage of the disease could help reverse symptoms and aid in the patient gaining a better quality of life. There are a lot of research studies that are carried out on Alzheimer’s disease and exercise is found to be one of the most important lifestyle factors that could help delay this condition. The identification of the effectiveness of statins in lowering Alzheimer’s disease risk could prove to be another important step towards better care for Alzheimer’s disease.

References:

1. Cholesterol and Statins in Alzheimers - (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3248784/)

Source-Medindia