Moderate exercise may help delay the development of Alzheimer's disease biomarkers in at-risk older adults, according to three studies presented at the 2019 American Psychological Association convention.
In the first study, Ozioma Okonkwo, PhD, assistant professor at University of Wisconsin School of Medicine and Public Health, and colleagues examined 317 individuals with a family history of probably Alzheimer’s disease enrolled in an ongoing observational study, the Wisconsin Registry for Alzheimer's Prevention.
Cognitively healthy participants aged 40 to 65 years at the time of enrollment received assessment of biological, health and lifestyle factors related to Alzheimer’s disease and follow-up assessments every two to four years, according to a press release. Participants also completed questionnaires on their physical activity and underwent neuropsychological evaluation and brain scans to measure biomarkers associated with the disease.
The data revealed a reduction in cognitive abilities and an increase in biomarkers associated with Alzheimer’s disease in adults older than 60 years compared with younger adults. However, in older adults who engaged in at least 30 minutes of moderate exercise 5 days a week, these effects were significantly reduced, according to the press release.
"Our research shows that, in a late-middle-age population at risk for Alzheimer's disease, physically active individuals experience fewer age-related alterations in biomarkers associated with the disease, as well as memory and cognitive functioning," Okonkwo said in a press release. “The most interesting part of our research is that we now show evidence that lifestyle habits — in this case regular, moderate exercise — can modify the effect of what is commonly considered a nonmodifiable risk factor for Alzheimer's, in this case aging.”
In the second study presented at the meeting, Okonkwo and colleagues examined 95 individuals from the Wisconsin Registry for Alzheimer's Prevention with Alzheimer’s disease polygenic risk scores to determine whether biomarkers changed with genetic risk and whether aerobic fitness affected this relationship. The researchers found that individuals with higher polygenic risk scores also demonstrated increased Alzheimer’s biomarkers, but that this effect was weaker in those with greater aerobic fitness.
In the third study, in which the investigators assessed MRIs from 107 individuals from the registry while they ran on a treadmill to determine their oxygen uptake efficiency slope (a measure of aerobic fitness), the researchers reported a significant increase in white matter hyperintensities — a biomarker of Alzheimer’s — in older participants that was lessened in those with high levels of aerobic fitness, according to the release.
"Overall, these studies suggest that the negative effect of aging and genetic risk on Alzheimer's' disease biomarkers and cognition can be lessened in physically active, older adults at risk for the disease compared with their less active peers," Okonkwo said in the release. "If these findings are supported by more prospective, controlled studies, it would provide compelling evidence for physical activity as an effective approach to prevention, particularly in at-risk populations." – by Savannah Demko
Okonkwo O, et al. “Worried about Alzheimer's disease? Lifestyle (and good genes) holds the key.” Presented at: 2019 American Psychological Association Convention; Aug. 8-12; Chicago.
Disclosures: Healio Psychiatry was unable to confirm any relevant financial disclosures at the time of publication.