What were the findings of the 90+ study?

The 90+ Study, initiated in 2003 by the University of California, Irvine, is one of the largest and longest-running studies focused exclusively on the fastest-growing age group in the United States—people aged 90 and older. Its key findings challenge common assumptions about aging, lifestyle, and cognitive decline.

Quick Summary

The 90+ Study found that moderate alcohol and coffee consumption, being slightly overweight in your 70s, and engaging in physical and social activities are associated with living longer. It also revealed a high prevalence of dementia and disability in this age group, but many with normal cognition have brain pathologies similar to Alzheimer's patients.

Key Points

• Moderate Habits Linked to Longevity: The study found that moderate consumption of alcohol and coffee was associated with a longer lifespan compared to abstention.

• Being Overweight in Your 70s is Protective: Contrary to some advice, individuals who were slightly overweight in their 70s lived longer than those who were normal or underweight.

• Brain Pathology Doesn't Always Mean Dementia: Many cognitively intact people over 90 had significant brain pathology (plagues and tangles), indicating a resilience to cognitive decline.

• Dementia Risk Keeps Rising: The incidence of dementia continues to increase exponentially even after age 90, debunking theories of a plateau.

• High Rates of Disability: A high percentage of people over 90 experience disability, which increases with age and is more common in women.

• APOE2 Gene's Protective Role: Individuals with the APOE2 gene showed a lower risk of clinical Alzheimer's, despite often having significant brain pathology.

Uncovering the Secrets of Super-Agers

Started in 2003, The 90+ Study at UCI MIND investigates factors contributing to longevity and healthy aging in individuals aged 90 and older. By following a cohort from a previous study, researchers aimed to understand what allows some people to live into their tenth decade and beyond. The study's findings have provided significant insights into the aging process.

Surprising Links to Longevity

The 90+ Study revealed several unexpected associations with living longer, particularly concerning lifestyle habits.

Diet, Activity, and Social Life

Findings suggest that moderate daily consumption of both alcohol and coffee is associated with a longer lifespan compared to abstaining. Being slightly overweight in your 70s was also linked to living longer than being normal or underweight at that age. The study found no association between taking supplemental vitamins A, C, or E and increased longevity. Regular physical activity, up to about 45 minutes daily, was associated with increased longevity, and engaging in non-physical activities for at least an hour daily also showed benefits. Maintaining social engagement was another factor associated with living longer.

Dementia and Cognitive Health in the Oldest-Old

The study provided critical data on memory and dementia in nonagenarians and centenarians, highlighting the complex relationship between brain pathology and cognitive function.

The Paradox of Brain Pathology

A significant finding is that many individuals with superior cognitive function in their 90s have similar brain pathology—amyloid plaques and neurofibrillary tangles—as those diagnosed with Alzheimer's disease. This suggests some individuals possess cognitive resilience, allowing them to tolerate considerable pathology without significant impairment. Conversely, about half of participants who developed dementia did not have sufficient brain pathology to explain their decline, indicating other contributing factors.

Dementia Risk and Genetic Factors

The incidence of dementia rises exponentially in the 90+ age group, doubling approximately every five years, and is more common in women. The study identified that individuals with the APOE2 gene are less likely to develop clinical Alzheimer's dementia, despite potentially having Alzheimer's neuropathology in their brains.

Disability and Functional Decline

The 90+ Study also provided a clearer picture of disability prevalence in the oldest-old.

Rising Disability Rates

Disability is highly prevalent in people aged 90 and older and increases with age. Difficulty walking was the most common issue, while bathing was the most common dependency. Participants in institutions were significantly more likely to be disabled than those living independently.

Comparative Findings on Aging Factors

The 90+ Study's results challenge some common assumptions about aging:

Assumption About Aging	Finding from the 90+ Study	Implications
Abstaining from alcohol is best for longevity.	Moderate alcohol and coffee intake are associated with living longer.	Moderation, not abstinence, may be key for the oldest-old.
Staying slim is best for longevity.	Being slightly overweight in your 70s was linked to a longer lifespan.	A slightly higher BMI might be protective in very old age.
Brain plaques and tangles always cause dementia.	Many cognitively intact 90-year-olds have significant brain pathology, suggesting cognitive resilience.	Brain health is complex, and other factors contribute to cognitive function.
Dementia incidence plateaus in the oldest-old.	Incidence of dementia continues to double every five years past 90.	The oldest-old face an extraordinary risk of dementia, highlighting a major public health issue.
Vitamin supplements prolong life.	Supplemental vitamins A, C, and E were not associated with increased longevity.	The protective effects of vitamins may not be significant for longevity in this group.

Conclusion: A Complex Picture of Longevity

The 90+ Study highlights that while lifestyle choices are linked to longer life, genetic and biological factors also play a significant role. The discovery of cognitive resilience in the face of significant brain pathology offers hope and new research avenues. As the oldest-old population grows, these findings are crucial for public health and care strategies.

For more information on the fascinating work being done by the University of California, Irvine, you can visit the UCI MIND website.

Frequently Asked Questions

What is the 90+ Study?

The 90+ Study is an ongoing research project at the University of California, Irvine, that began in 2003 to study the health and lifestyles of people aged 90 and older. It follows a cohort of participants who were previously part of an earlier study from the 1980s.

Did the 90+ Study find that alcohol is good for you?

The study found an association, not a causal link, between moderate alcohol consumption and increased longevity in its participants. Specifically, people who drank moderately lived longer than abstainers. This is an observational finding specific to this very old age group and should not be taken as general health advice.

How did the 90+ Study investigate the brain?

The study included a brain donation program, allowing researchers to perform autopsies and compare brain pathology with cognitive test scores taken during the participants' lives. This method allowed them to discover the disconnect between typical Alzheimer's pathology and cognitive function in many oldest-old individuals.

What did the study say about body weight and longevity?

The research revealed that being slightly overweight in one's 70s was associated with living longer than being normal or underweight. This is another finding specific to the oldest-old and suggests a potentially different optimal weight range in advanced age.

Does the 90+ Study suggest vitamins are not helpful for aging?

The study found no association between taking supplemental vitamins A, C, or E decades earlier and increased longevity. The findings do not necessarily negate the importance of a balanced diet rich in vitamins but indicate that supplements may not be a magic bullet for living longer.

What factors were linked to disability in the 90+ Study?

The study found that disability, defined by difficulties with Activities of Daily Living (ADLs), was highly prevalent and increased with age. Key factors associated with disability included age, gender (more common in women), and institutionalization.

Why is the 90+ Study so significant?

The study is significant because it focuses on the oldest-old, the fastest-growing age group, for whom very little data was previously available. The findings have challenged conventional wisdom about aging, longevity, and dementia, providing unique insights into health at the extreme end of life.