Do Lifestyle and Genetics Play a Role in the Development of Dementia?

Around the globe, Alzheimer’s and other types of dementia are a major challenge to the people suffering from it, their families, and the communities in which they reside. To add to the situation, there are limited remedies available to prevent and treat the dreaded disease, not to mention the underlying causes, which are debated by medical professionals far and wide. Thus far, attempts at fighting, or even slowing down, the progress of Alzheimer’s and dementia have been largely unsuccessful. Taking an entirely different approach, experts now hope to intervene even before a diagnosis is made by encouraging positive lifestyle changes.

What Is Dementia?

Dementia is described as a group of diseases that have symptoms characterized by memory loss. Alzheimer’s disease is one of the most common types of dementia. People who have Alzheimer’s all have one thing in common when it comes to their brain chemistry: they all have plaques that consist of tangled proteins. According to recent research, these plaques are likely where the root of the disease can be found. Vascular dementia is another type of dementia and the prevailing hypothesis is that it stems from damage to blood vessels in the brain, such as that caused by a stroke.

Exploring the Factors That Affect the Risk of Dementia

Experts claim that both genetics and one’s lifestyle play a crucial role in the development of dementia. While genes cannot be modified, an individual’s lifestyle can be altered. A study conducted recently consisted of an attempt to assess the extent to which the development of dementia is influenced by genetic and lifestyle factors. The study involved the analysis of data from a biobank based in the UK. Biobanks are created to link massive amounts of biological data, e.g. genetics, with information collected from medical data. Observation of the results makes it possible for researchers to gain valuable insights into how environmental factors and genetics may work together to increase or decrease the risk of disease. The study also reviewed hospital records and death registries to collect a thorough amount of medical information generated by 200,000 British individuals aged 60 years or older.

How Can Lifestyle and Genetic Risk Be Measured?

The research team hand-picked a list of typical lifestyle factors like diet, physical activity, smoking, and alcohol consumption to create a scoring system in which a low score indicated a “bad” lifestyle and a high score indicated a “good” lifestyle. It should be noted that this approach does pose several potential drawbacks:

• There are several lifestyle factors that were not considered.
• A diet considered “good” may be disputable.
• A scoring system makes the role of each lifestyle factor uncertain and not necessarily independent.

To create a genetic risk score, researchers used several variants that have been identified by a previous study of Alzheimer’s disease. These variants have already been solidly established as part of the genetic make-up of people with Alzheimer’s. This data was used to create a polygenic risk score.

Genetics and Lifestyle Are Both Significant in Dementia

Findings indicated that both lifestyle and genetic score were linked to the risk of dementia. This means that people with low scores in either are at a higher risk of dementia. Researchers further discovered that genes and lifestyle factors were independent of one another so that people with low scores in both have a significantly higher risk than those who, for example, may have a low score when it comes to lifestyle but a high score when it comes to genetics.

Nevertheless, this study was not created with the aim of proving that lifestyle, environmental factors, or genetics cause dementia. Therefore, there may be other factors that could explain the disparity amongst people who develop the disease. Should individuals who have a high genetic risk of Alzheimer’s change their lifestyles and their lifestyles were possibly a cause of Alzheimer’s, then only one out of over 120 cases may be prevented in ten years. Without discounting the significance of that, the question remains as to how many lifestyle changes would be required to prevent Alzheimer’s in a higher number of people. Do genetics even play a major role? There also was no indication that genetic and lifestyle factors work together to cause Alzheimer’s.

What’s Next?

The next step is to establish how genetics associated with ethnicity increase or decrease the risk of Alzheimer’s. Until now, genetic studies have mainly been focused on Caucasians. Risk factors based on gender should also be further explored, and causation needs to be established, if possible.

Biobanks are only able to describe the association between lifestyle changes and the risk of dementia. The establishment of causation, however, necessitates randomized experiments.

At the end of the day, living a healthy lifestyle can’t hurt when trying to avoid dementia. Going forward, though, studies that involve biobanks may be able to help reach better conclusions about the millions of people already affected by this horrible disease.

This matter is particularly important to us at The Northern Charitable Foundation, in Isreal we founded the Tzipora Fried Alzheimer center, there we provide information, support and guidance to families.