Less cognitive decline, more cognitive resilience among ‘oldest-old,’ study finds
Older adults with a long lifespan—particularly centenarians—experienced slower cognitive decline, shorter periods of cognitive impairment, and maintained better cognitive function compared to their peers with shorter lifespans, according to a new study led by Harvard T.H. Chan School of Public Health.
The study was published Oct. 22 in Alzheimer’s & Dementia. Yuan Ma, assistant professor of epidemiology, was the corresponding author.
Previous studies have observed cognitive resilience among centenarians but otherwise haven’t clearly established the trajectories of cognitive decline among individuals of varying lifespans. To fill this gap, the researchers analyzed data on older adults’ cognitive health collected by Alzheimer’s Disease Research Centers across the country and made public by the National Alzheimer’s Coordinating Center. The study included 13,999 participants, ages 50 to 100+, whose cognitive health was monitored for an average of five years before their death. Brain autopsies were conducted on more than 8,000 of the participants, making neuropathological data available. The researchers also considered participants’ sociodemographic data.
The study found that people with longer lifespans—the “oldest-old”—maintained good cognitive function for more years than their peers who died earlier, and also had more cognitive resilience. Among nonagenarians, for example, the median period of living with dementia before death was 2.4 years; among centenarians, it was 1.1 years. The researchers observed that women, white people, and individuals free from cardiovascular disease had the greatest cognitive resilience among those who died before age 90. APOE ε2, a genetic variant known to be associated with longevity and a decreased risk of Alzheimer’s disease, was associated with higher cognitive resilience only among centenarians.
“These findings support the hypothesis of the compression of cognitive morbidity in late life and highlight the importance of cognitive resilience in achieving healthy aging,” the researchers wrote. “Intervention strategies that improve cognitive resilience might help extend lifespan with healthy cognitive function.”
Read the study:
Compression of Cognitive Decline and Cognitive Resilience in Extreme Longevity
