Could Healthy Lifestyle Help Those at High Genetic Risk for Dementia?

By Kelly Young

Adherence to a healthy lifestyle is associated with reduced risk for dementia, even among those who are genetically predisposed, according to a JAMA study presented at the Alzheimer’s Association International Conference.

Nearly 200,000 adults who were white, aged 60 years and older, and without baseline cognitive impairment had polygenic risk for dementia assessed and completed lifestyle questionnaires. A favorable lifestyle consisted of three or four of the following:

• Not currently smoking
• Regular physical activity (e.g., 150 min/week of moderate or 75 min/week of vigorous activity)
• Healthy diet
• Low-to-moderate alcohol intake (0-1 standard drink for women, 0-2 drinks for men)

During a median 8 years’ follow-up, 0.9% were diagnosed with dementia. Both genetic risk and lifestyle were independently associated with dementia risk. Among those at high genetic risk, a favorable lifestyle was associated with an absolute risk reduction in dementia of 0.65%, compared with those who had an unfavorable lifestyle (0-1 factors).

If the relationship is causal, the authors write, one case of dementia “would be prevented for each 121 individuals per 10 years with high genetic risk who improved their lifestyle from unfavorable to favorable.”