The new research was the work of researchers based in Spain and the United States. It was published yesterday in the prominent journal Nutrients.
Decades worth of data
The research used data gathered from the Framingham Offspring Cohort, which was established in 1971 as a follow-on to the original Framingham Health Study, which began in 1948. The original goal of that research was to find causative factors for heart disease, but as with other large population studies, such as NHAHES, the data gathered has been used to answer additional research questions as time went on.
Of the more than 5,000 initial participants in the Offspring enrollment, the data from 1,490 subjects who were older than 65 and free of dementia was included in the present study. They included having the APOE-ε4 gene—which heightens the risk of developing Alzheimer’s disease—as an additional data point.
The study tested the blood of the subjects from their periodic visits as part of the program. The blood was analyzed for its omega-3 content in red blood cell tissue. The cohort was divided into quintiles based on that measure. The subjects’ cognitive performance was assessed using the Mini-Mental State Examination, a standard tool for cognitive testing.
49% reduced risk
The results were striking. The authors found that the highest quintile had a 49% lower risk of incident Alzheimer’s disease than did the lowest quintile. Being in the highest quintile was predicted to provide an additional 4.7 years of life free from Alzheimer’s symptoms.
The authors also said that more DHA might lower the risk of developing Alzheimer’s, and might be of particular benefit for those carrying the APOE-ε4 gene.
“Our results, which concur with a growing experimental research foundation, suggest that an increased DHA intake may be a safe and cost-effective strategy in preventing AD in specific populations,” they concluded.
Huge cost savings
The researchers noted that, ”Given that estimated health-care payments in 2021 for all patients with AD or other dementias amount to $355 billion in the US (not including caregiving by family members and other unpaid caregivers), any cost-effective strategy for delaying the onset of AD is of utmost public health interest.“
"Delaying AD by 5 years leads to 2.7 additional years of life, and 4.8 additional AD-free years for an individual who would have acquired AD and is worth over $500,000,” they added.
William S. Harris, PhD, head of the Fatty Acid Research Institute and one of the papers authors, said what’s particularly noteworthy is that this result is very similar to one obtained more than 15 years ago using the original Framingham Health Study cohort. In that study, which used a slightly different method to measure DHA in the tissues, the highest group had a 47% reduced risk of developing Alzheimer’s.
“This is one of the stronger findings in the field,” Harris said.
Source: Nutrients
2022, 14, 2408. https://doi.org/10.3390/nu14122408
Red Blood Cell DHA Is Inversely Associated with Risk of Incident Alzheimer’s Disease and All-Cause Dementia: Framingham Offspring Study
Sala-Vila, et. al.