BACKGROUND AND PURPOSE:

• Dhana et al. (BMJ, 2022) sought to determine whether an increased life expectancy through lifestyle modifications influences the overall years lived with Alzheimer’s dementia across the lifespan

METHODS:

• Prospective cohort study
  • The Chicago Health and Aging Project
  • Designed to assess the risk factors of Alzheimer’s dementia in the general population
• Participants
  • Men and women
  • ≥65 years
• Exposures
  • A healthy lifestyle score, based on 5 modifiable lifestyle factors
    • 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 to 15 g/day; men 1 to 30 g/day)
• Study design
  • In-home assessments: Structured self or interviewer administered questionnaires
  • Neurocognitive tests administered every three years up to six times throughout the study
  • Study included biospecimen collection
• Primary outcome
  • Life expectancy, with and without Alzheimer’s dementia, in women and men

RESULTS:

• 2449 participants

Women 65 Years of Age 

• Women with 4 or 5 healthy factors lived 3.1 years longer than women with zero or 1 healthy factor
  • 4 or 5 healthy factors: Life expectancy 24.2 years (95% CI, 22.8 to 25.5)
  • 0 or 1 healthy factors: 21.1 years (95% CI, 19.5 to 22.4)
• Remaining years spent with Alzheimer’s dementia
  • 4 or 5 healthy factors: 10.8% (2.6 years; 95% CI, 2.0 to 3.3)
  • 0 or 1 healthy factor: 19.3% (4.1 years; 95% CI, 3.2 to 5.1)
• Life expectancy for women without Alzheimer’s dementia
  • 4 or 5 healthy factors: 21.5 years (95% CI, 20.0 to 22.7)
  • 0 or 1 healthy factor: 17.0 years (95% CI, 15.5 to 18.3)

Men 65 Years of Age

• Men with 4 or 5 healthy factors lived 5.7 years longer than men with 0 or 1 healthy factor
  • 4 or 5 healthy factors: life expectancy 23.1 years (95% CI, 21.4 to 25.6)
  • 0 or 1 healthy factor: 17.4 years (95% CI, 15.8 to 20.1)
• Remaining years spent with Alzheimer’s dementia
  • 4 or 5 healthy factors: 6.1% (1.4 years; 95% CI, 0.3 to 2.0)
  • 0 or 1 healthy factor: 12.0% (2.1 years; 95% CI, 0.2 to 3.0)
• Life expectancy for men aged 65 without Alzheimer’s dementia
  • 4 or 5 healthy factors: 21.7 years (95% CI, 19.7 to 24.9)
  • 0 or 1 healthy factor: 15.3 years (95% CI, 13.4 to 19.1)

CONCLUSION:

• Living a healthy lifestyle was associated with longer life expectancy for both men and women
• Those that lived a healthy lifestyle also lived more of their remaining years without Alzheimer’s dementia
• The authors state

A healthy lifestyle was associated with a longer life expectancy among men and women, and they lived a larger proportion of their remaining years without Alzheimer’s dementia

The life expectancy estimates might help health professionals, policy makers, and stakeholders to plan future healthcare services, costs, and needs

Learn More – Primary Sources:

Healthy lifestyle and life expectancy with and without Alzheimer’s dementia: population based cohort study

Related ObG Topics:

Lancet Commission: Over a Third of Dementia Cases May be Preventable

Does a Healthy Lifestyle Decrease Risk of Dementia Even in Those with High Genetic Risk?

Is there an Association between Multiple Morbidities and Subsequent Dementia?  

Is Midlife Cardiovascular Fitness Associated with Reduced Risk for Dementia?