Subjective cognitive decline and total energy intake: Talk too much?

Area of Science:

• Gerontology and Neuroscience
• Public Health and Epidemiology

Background:

• Dementia, particularly Alzheimer's disease, is a growing cause of death and disability due to increased longevity.
• Understanding the early stages of dementia is crucial, with current hypotheses focusing on aging, vascular disease, and metabolic factors.
• Alzheimer's disease has a prolonged incubation period involving amyloid deposition, neurodegeneration, and cognitive decline.

Purpose of the Study:

• To investigate the association between higher energy intake and the very early symptoms preceding mild cognitive impairment and dementia.
• To explore potential explanations for an observed unusual correlation between energy intake and dementia symptoms.

Main Methods:

• Analysis of dietary intake data from the Nurses' Health Study and the Health Professionals Follow-up Study.
• Examination of the relationship between energy consumption and the incidence of early dementia-related symptoms.
• Statistical assessment to determine correlations between dietary intake, body mass index, and reported symptoms.

Main Results:

• Higher energy intake was associated with very early symptoms indicative of mild cognitive impairment and dementia.
• This association was not correlated with body mass index, an unexpected finding.
• The unusual observation suggests a potential role for reporting bias in the study's results.

Conclusions:

• The study highlights a potential, albeit unusual, link between high energy intake and early dementia symptoms.
• Reporting bias is proposed as a likely explanation for the observed association, given the lack of correlation with body mass index.
• Further investigation is warranted to clarify the complex interplay between diet, reporting, and the initial stages of cognitive decline.