Genes known to fight cognitive decline are also linked to overall healthy aging, a Wellderly study has shown.
Researchers from Scripps Translational Science Institute (STSI) conducted an eight-year study, also called Wellderly, which analyzed the genomic sequence of healthy aging and has found a high number of genetic variants that are known to prevent cognitive decline.
The American Heart Association has previously reported that individuals with healthy hearts have better cognitive functions. This time, the study showed that better cognitive aging is associated with general healthy aging.
Early findings of the Wellderly have suggested that long-term cognitive health has a significant protective effect on chronic diseases such as diabetes, heart disease, and cancer. Chronic diseases account for as much as 90 percent of mortality in the U.S. and take up about 75 percent of total health care spending.
Dr. Eric Topol, STSI Director and senior study author, said those included in the study have an age range of 80 to 105 years and have no diagnosed chronic medical diseases. Using genomic sequencing, the researchers studied the whole genomes of 600 participants and correlated them with genetic data collected by Inova Translational Medicine Institute (ITMI) from 1,507 adults, which represented the general population.
DNA mapping and analysis showed that adults from the Wellderly group have a lower genetic risk of developing coronary artery disease (CAD) and Alzheimer's disease. However, the two groups did not have any significant difference in the risk for stroke, diabetes, or cancer and this may mean that genes that play a part in cognitive health offer protective characteristics.
"We found weaker signals among common as well as rare variant sites, which collectively suggest that protection against cognitive decline contributes to healthy aging," said Ali Torkamani, study author and director of genome informatics at STSI.
"Our findings indicate that protection from cognitive decline is associated, not necessarily cause and effect, with healthspan," said Dr. Topol.
Researchers found a group of ultra-rare coding variant in the COL25A1 gene in 10 Wellderly adults. COL25A1 plays a crucial role in the encoding of amyloid plaques in patients with Alzheimer's disease. None of these coding variants were noted in the genomic sequences of ITMI individuals.
Researchers acknowledged that only a few studies about healthspan exist and their population is limited. By making the genomic data available to researchers, Topol hopes that a larger and more in-depth study about healthspan would be carried out. At present, there are more than 1,400 participants in the ongoing study.
The study is published in Cell.
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