healthy lifestyle and life expectancy with and without Alzheimer’s dementia

Last edited 05/2023 and last reviewed 05/2023

Data from a population based cohort study in the US (n=2449) found adherence to a healthy lifestyle was associated with a longer life expectancy and fewer years lived with Alzheimer's dementia across the lifespan

• a healthy lifestyle score was developed based on five modifiable lifestyle factors:
  • a diet for brain health (Mediterranean-DASH Diet Intervention for Neurodegenerative Delay-MIND diet score in upper 40% of cohort distribution),
  • late life cognitive activities (composite score in upper 40%),
  • moderate or vigorous physical activity (>=150 min/week),
  • no smoking,
  • light to moderate alcohol consumption (women 1-15 g/day; men 1-30 g/day)
• on average, the total life expectancy at age 65 in women and men with 4 or 5 healthy factors was 24.2 and 23.1 years, of which 10.8% and 6.1% were spent with Alzheimer's dementia
• for women and men with 0 or 1 healthy factor, life expectancy was shorter -21.1 and 17.4 years -and more of their remaining life expectancy was spent with Alzheimer's dementia (19.3% and 12.0%, respectively)
• study authors concluded:
  • healthy lifestyle was associated with a longer life expectancy among men and women, and with a larger proportion of remaining years lived without Alzheimer's dementia

According to an editorial (2):

• these findings have important implications for the wellbeing of aging populations and for related public health policies and programmes
• notes both Alzheimer's disease and other dementias are among the most expensive health conditions both economically and socially
  • number of people living with Alzheimer's disease and other dementias is expected to treble worldwide in a few decades, from an estimated 57 million in 2019 to 152 million in 2050
  • in the United States, more than one in nine people aged 65 and older had dementia in 2021
• highlights that the development and implementation of intervention programmes to reduce the risk of these conditions is critically important in global efforts to reduce pressure on stressed healthcare systems, healthcare workers, and both paid and unpaid carers
• suggests that promoting greater engagement in healthy lifestyles may increase dementia-free life years - by delaying the onset of dementia without extending life years spent with dementia

Mediterranean-Dietary Approaches to Stop Hypertension (DASH) and dementia risk

• evidence that the Mediterranean diet may potentially reduce dementia risk, but further investigations are needed in different populations (3)

Reference:

• Dhana K, Franco O H, Ritz E M, Ford C N, Desai P, Krueger K R et al. Healthy lifestyle and life expectancy with and without Alzheimer's dementia: population based cohort study BMJ 2022; 377 :e068390 doi:10.1136/bmj-2021-068390
• Choi H. Healthy lifestyles and more life years without dementia BMJ 2022; 377 :o885 doi:10.1136/bmj.o885
• Chen H, Dhana K, Huang Y, et al. Association of the Mediterranean Dietary Approaches to Stop Hypertension Intervention for Neurodegenerative Delay (MIND) Diet With the Risk of Dementia. JAMA Psychiatry. Published online May 03, 2023. doi:10.1001/jamapsychiatry.2023.0800