New research has identified that seven healthy habits and lifestyle factors may provide effective dementia prevention, even among people with the highest genetic risk of the disease.
“Life’s Simple 7’ are seven cardiovascular and brain health factors developed by the American Heart Association, which includes eating better, exercising, losing weight, not smoking, maintaining healthy blood pressure, reducing blood sugar, and controlling cholesterol. Research published in Neurology suggests that implementing these strategies aids dementia prevention, even in individuals with an elevated genetic risk.
Adrienne Tin, PhD, the author of the study from the University of Mississippi Medical Center, commented: “These healthy habits in the Life’s Simple 7 have been linked to a lower risk of dementia overall, but it is uncertain whether the same applies to people with a high genetic risk. The good news is that even for people who are at the highest genetic risk, living by this same healthier lifestyle are likely to have a lower risk of dementia.”
Analysing dementia risk
The investigation followed participants for 30 years, 8,823 of which had European ancestry and 2,738 African ancestries, who had an average age of 54 at the study’s inception. The individuals reported their levels for all seven health factors.
Scores ranged from 0 to 14, with 0 representing the most unhealthy score and 14 the healthiest. The average score among people with European ancestry was 8.3, whereas the average was 6.6 in individuals with African ancestry. Additionally, the researchers calculated genetic risk scores for the participants at the start of the study by employing genome-wide statistics on Alzheimer’s disease.
Based on their genetic risk scores, the team divided the people with European ancestry into five groups and those with African ancestry into three groups. Participants placed in the highest genetic dementia risk group included people with at least one copy of APOE e4 – an APOE gene variant associated with Alzheimer’s disease.
In the European groups, 27.9% had the APOE e4 variant. However, the variant was found to be much more prevalent among participants with African ancestry, with 40.4% carrying APOE e4. Individuals in the lowest risk group carried the APOE e2 variant, which previous research has attributed to decreasing dementia risk. At eh study’s conclusion, 1,603 of the participants with European ancestry developed dementia, and 631 with African ancestry developed dementia.
How did healthy habits impact dementia prevention?
The result signified that implementing Life’s Simple 7 can significantly enhance dementia prevention, illuminating that people with European ancestry with the highest lifestyle factor scores had the lowest dementia risk across all five genetic risk groups, even the group with the highest dementia risk. Furthermore, dementia risk was lowered by 9% for every one-point increase in the lifestyle factor score.
Among people with European ancestry, people with intermediate or high scores in lifestyle factors had a 30% and 43% lower dementia risk than those with the lowest scores, demonstrating the powerful effects of healthy habits on dementia prevention.
In people with African ancestry, the intermediate and high scores categories were associated with a 6% and 17% lower dementia risk. The team identified declining dementia risk among all three groups with higher lifestyle factor scores in these participants.
Although the investigation results may help develop future strategies for dementia prevention, the researchers explained that due to the small sample size of people with African ancestry and that they were recruited from one location, further studies are required to validate their results.
Tin concluded: “Larger sample sizes from diverse populations are needed to get more reliable estimates of the effects of these modifiable health factors on dementia risk within different genetic risk groups and ancestral backgrounds.”
