Researchers are particularly interested in lifestyle modifications and interventions that may delay the onset of Alzheimer’s disease.
According to estimates, implementing healthy lifestyle practices could potentially avert about 40% of dementia cases globally.
In an effort to avoid cognitive decline in older persons, a study that was published in JAMA Neurology examined the impact of lifestyle interventions on cognition.
In addition, researchers specifically studied deceased people who had undergone post-mortem exams in order to determine whether lifestyle factors affect cognition before death.
The Rush Memory and Aging Project (Rush MAP), a 24-year longitudinal clinical-pathological investigation, provided the data for this extensive analysis.
In addition to doing a comprehensive neuropathological diagnosis at the time of autopsy, researchers examined individual data on 754 dead participants as well as their lifestyle characteristics.
Lifestyle :
Of the 754, 586 had complete post-mortem records, scientific evaluations, and information on their food and lifestyle. Researchers compared study-relevant genetic variables with MAP-eligible genetic traits, as well as participant demographics like age, gender, and educational attainment.
A 144-item Food Frequency Questionnaire (FFQ) was used to estimate food intake. Participants answered questions about how frequently they typically consumed different foods over the previous 12 months. An alcohol-free diet score was used to evaluate the overall quality of the diet.
A questionnaire measuring participation in intellectually stimulating activities (e.g., reading, visiting museums, and playing games like cards, chess, crosswords, or puzzles) over the previous year was also used to estimate intellectual activity.
In addition, physical activity estimates were evaluated using a survey created especially for senior citizens. The time spent on moderate-to-intense physical activities, such as walking, yard work, swimming, cycling, and calisthenics, had to be self-reported by the participants. Finally, self-reported surveys were used to gauge alcohol consumption.
Participants were classified as “healthy” or at a lower risk based on these criteria if they were among the top 40% of the population under analysis.
(corresponding to an activity score of 3.20 and a diet score of over 7.5). In addition, a healthy lifestyle score comprised not smoking at the time of self-report, moderate alcohol intake (up to 15 grams per day for women and 30 grams per day for males), and at least 150 minutes per week of moderate to intense physical activity.
Brain exams were carried out after a subject died to see if Alzheimer’s disease or consciousness was still present. Quantification of β-amyloid deposition, phosphorylated tau tangles, neuritic and diffuse plaques, neurofibrillary tangles, and other pathological indicators was done using a variety of approaches. In addition, certain brain regions were subjected to immunohistochemistry and staining procedures in order to evaluate the neuropathology of Alzheimer’s disease and related disorders such as atherosclerosis, Lewy body disease, and hippocampus sclerosis.
Nineteen tests were utilized to evaluate annual cognitive function. Each test result was normalized based on the mean baseline, and the composite score from the nineteen tests was used to determine total global cognitive function.
Higher cognitive performance was indicated by positive ratings, and lower cognitive performance was indicated by negative scores.
According to the study’s findings, healthier lifestyles, or higher lifestyle ratings, were linked to improved cognitive function prior to death. Moreover, relationships between lifestyle and cognition were not influenced by the neuropathology of Alzheimer’s disease, even when β-amyloid was responsible for about 12% of cases.
Despite the burden of dementia-related neuropathology, the authors emphasized that this finding supports the relevance of lifestyle in maintaining cognitive function in older persons.
Additionally, by lowering vascular burden, lifestyle modifications may lessen the incidence of Alzheimer’s disease.
These findings support earlier research that suggested diet and physical exercise are independently linked to both vascular health and cognitive function. The authors of the study hypothesize that lifestyle elements that can reduce inflammation and oxidative stress, such as physical activity and nutrition, have antioxidant and anti-inflammatory qualities that may explain the association between lifestyle and cognition. In order to gain a better understanding of the relationship between lifestyle and cognition before death, the authors emphasize the need for additional study into particular correlations between lifestyle factors and markers of brain inflammation.
The study’s shortcomings include its observational design, which limits generalizability, its
reliance on self-reported lifestyle factors—which may introduce biases—and the possible
effects of some lifestyle factors, like physical activity, on one’s capacity to implement lifestyle
recommendations. The authors further stress that because the study was observational in
nature, it is not possible to ascertain the cause of the relationships that have been identified.
