Do lifestyle factors influence late-life cognition and dementia pathology?

In a recent study published in the journal JAMA NeurologyScientists at Rush University Medical Center in Chicago, USA, have found that dementia-related brain pathology, such as cerebrovascular pathology, phosphorylated tau fibrillar changes, and beta-amyloid accumulation, can be improved by healthy lifestyle choices and after dementia. We investigated whether this would change the association with dementia. Years of life.

background

Increasing research in the field of dementia and Alzheimer's disease has reported that shifting to healthy lifestyle choices can reduce the risk of these diseases, and is helping the world's population move towards healthier lives. It has been reported that if we make significant changes, we could theoretically prevent around 40% of dementia cases worldwide. Lifestyle. Previous research by the same team of scientists also reported that a healthier lifestyle was associated not only with longer life expectancy, but also with a longer life without Alzheimer's disease.

Based on these findings, various clinical trials around the world are investigating the effectiveness of lifestyle changes in middle-aged and older adults in preventing cognitive decline. However, brain pathologies associated with dementia, such as phosphorylated tau fibril changes and beta-amyloid burden, are thought to accumulate with age long before the onset of dementia. It remains unclear whether this age-related accumulation of brain pathology alters the impact of a healthy lifestyle in preventing dementia.

About research

In this study, researchers used autopsy data obtained from a longitudinal study of clinical pathology and 24 years of follow-up, including neuropathological evaluation, cognitive testing, and lifestyle factors such as cognitive and physical exercise and diet. The information was used to conduct a cohort study. , smoking behavior, and alcohol intake.

They aimed to assess how these lifestyle factors are associated with cognitive performance approaching death and whether postmortem findings regarding dementia-related brain pathology influence this association. It was. Furthermore, the role of vascular diseases such as arteriosclerosis, infarction, and cerebral atherosclerosis in changing the association between lifestyle factors and cognition was also investigated.

Alzheimer's disease, transactivation response element (TAR) deoxyribonucleic acid (DNA) binding protein 43 (TDP-43), hippocampal sclerosis, and Lewy body type.

Self-reported lifestyle factors such as current non-smoking behavior, adherence to recommended levels of physical activity, limiting alcohol intake, and exceeding defined cut-off scores for targeted diets to reduce risk of cognitive decline. Cognitive activity scores were used. Develop a healthy lifestyle score.

The Mediterranean Diet Approach to Stop Hypertension (DASH), the Delayed Intervention for Neurodegeneration (MIND) diet, as the name suggests, is a combination of Mediterranean and hypertensive diets aimed at lowering the risk of dementia and cognitive decline. It is a combination of. A food frequency questionnaire was used to assess dietary intake, and other structured questionnaires were used to assess cognitive and physical activity levels.

While the healthy lifestyle score was exposure, the primary outcome measured was an overall cognitive score calculated based on a battery of 19 standardized cognitive tests. Measurements of brain pathology include detection of phosphorylated tau fibril changes, β-amyloid burden, disease pathology associated with Alzheimer's disease, cerebral vascular pathology, hippocampal sclerosis, TDP-43, and Lewy bodies.

result

The results suggested that a healthy lifestyle was associated with near-death cognitive decline, independent of brain pathology associated with Alzheimer's disease or dementia. Including dementia-related brain pathology in a multivariate model assessing the association between healthy lifestyle and cognitive activity scores did not affect the significance or strength of the association.

The researchers concluded that the association between lifestyle factors and cognition was largely independent of the brain pathology associated with Alzheimer's disease and dementia, although their findings suggest that beta-amyloid burden has a 12% influence. showed that. However, the researchers say that while these results should be interpreted with caution, they primarily support the positive impact that healthy lifestyle choices have on improving cognitive performance in older adults. I think it is.

The study also found that lifestyle factors such as physical activity and diet were associated with lower cognitive decline, independent of the effects of vascular disease. However, these findings may be the result of a study population consisting essentially of older adults, where vascular lesions in the brain are a consequence of age.

conclusion

Overall, the findings of this study indicate that healthy lifestyle factors may contribute significantly to reducing age-related cognitive decline in older adults, independent of neuropathology associated with dementia and Alzheimer's disease. I showed that.