This week I encountered a new paper that discusses the risk of getting dementia after age 55. The figures are alarming, especially given that, in addition to however many people will get dementia, another significant portion of people will experience cognitive decline that is not diagnosable as dementia but which will still be problematic in various ways.
Below are a few quotes from the paper:
“In the present study, our primary objective was to generate contemporary estimates of the lifetime risk of dementia, overall and across different population subgroups. We also characterized differences in the age of diagnosis and projected the number of new dementia cases that will develop in the United States over the next four decades. To achieve these aims, we analyzed over three decades of longitudinal data (1987–2020) from participants in the Atherosclerosis Risk in Communities (ARIC) study.”
“In this large community-based cohort study, 42% of participants developed dementia after midlife.”
“The median age of dementia diagnosis was 81 years (interquartile range: 77–86 years).”
“Our lifetime risk estimates are higher than those in previous population-based studies. In the Framingham Heart Study, 14% of men and 23% of women developed dementia from age 45–105 years. The lifetime risk of dementia (age 45–95 years) in the Rotterdam Study was 19% and 31% for men and women, respectively. The higher lifetime risk estimates in our analyses may reflect differences in dementia ascertainment. Previous research primarily relied on cognitive testing at study visits and a review of medical and death records to identify dementia. However, this may result in under-detection, because participants with cognitive impairment are less likely to attend in-person assessments, and administrative records lack sensitivity. In contrast, the ARIC study combined cognitive evaluations at study visits with intensive surveillance (phone interviews and review of hospital and death records) to maximize dementia ascertainment. Ongoing phone interviews with participants and informants were especially important, as they identified approximately half of all dementia cases in our study.”
“Policies focused on optimizing cardiovascular health and preserving hearing may be particularly important. Accumulating data from clinical trials have linked healthy lifestyle behaviors, the absence of vascular risk factors and hearing rehabilitation with improved cognitive outcomes. However, only approximately 20% of US adults are meeting recommended lifestyle and cardiovascular health targets, and only approximately 30% of older adults with hearing loss are using a hearing aid.”
- Lifetime Risk and the Projected Burden of Dementia from Michael Fang et al. (This is the actual paper, though it is behind a paywall.)
- Understanding Lifetime Risk and the Rising Burden of Dementia (Brief video with Josef Coresh who is one of the authors of the paper)
- United States Dementia Cases Estimated to Double by 2060 (Press release about the paper by NYU Langone)
Other Recommended Reading
- Aging and the Impact of Cognitive Decline on Investment Decisions from Larry Swedroe
- Never Pay a Medical Bill Without Asking These Questions First from Allie Volpe
- IRS Requires Sustained Funding to Continue to Help Taxpayers, Report Says from Martha Waggoner
- Aswath Damodaran, “Dean of Equity Valuation” (Bogleheads on Investing podcast episode by Rick Ferri)
- When Your Friends Are Richer Than You from Ben Carlson
- Do Stock Holdings Reflect Individual Risk Preferences or the Growing Use of Target Date Funds? from Alicia Munnell
- Doctors Can’t Spend More Than Half Their Income from Jim Dahle
Thanks for reading!


Hi. I'm Mike Piper, the author of this blog. I'm 


