Concurrent nutrient deficiencies are associated with dementia incidence.

INTRODUCTION: While observational research suggests a protective role for nutrition in brain aging, intervention studies remain inconclusive. This failing translation from observational to interventional research may result from overlooking nutrient interactions. METHODS: We developed a nutrient status index capturing the number of suboptimal statuses of omega-3 fatty acids, homocysteine, and vitamin D (range 0 to 3). We associated this index with dementia incidence in a subsample (age ≥ 50 years) of the Framingham Heart Study Offspring cohort. RESULTS: Among 968 participants, 79 developed dementia over 15.5 years (median follow-up). Each point increase in nutrient status index was associated with a 50% higher risk of dementia (hazard ratio [HR] = 1.50; 95% confidence interval [CI] = 1.16, 1.96). Participants with three high-risk statuses had a four-fold increased risk of dementia compared to participants without high-risk status (HR = 4.68; 95% CI = 1.69, 12.94). DISCUSSION: Concurrent nutrient deficiencies are associated with the risk of dementia. The potential of optimizing nutritional status to lower dementia risk warrants further study. HIGHLIGHTS: Nutrition and dementia research calls for multiple-nutrient approaches. We studied combined suboptimal statuses of omega-3 polyunsaturated fatty acids, homocysteine, and vitamin D. Suboptimal status of the three nutrients was associated with dementia risk. The risk estimate was larger than for other factors (ie, diabetes, apolipoprotein E Îµ4 carrier). Future studies should assess the effect of improving nutrient status on dementia risk.

Fornix fractional anisotropy mediates the association between Mediterranean diet adherence and memory four years later in older adults without dementia.

Here, we investigated whether fractional anisotropy (FA) of hippocampus-relevant white-matter tracts mediates the association between baseline Mediterranean diet adherence (MeDiAd) and verbal episodic memory over four years. Participants were healthy older adults with and without subjective cognitive decline and patients with amnestic mild cognitive impairment from the DELCODE cohort study (n = 376; age: 71.47 ± 6.09 years; 48.7 % female). MeDiAd and diffusion data were obtained at baseline. Verbal episodic memory was assessed at baseline and four yearly follow-ups. The associations between baseline MeDiAd and white matter, and verbal episodic memory's mean and rate of change over four years were tested with latent growth curve modeling. Baseline MeDiAd was associated with verbal episodic memory four years later (95 % confidence interval, CI [0.01, 0.32]) but not with its rate of change over this period. Baseline Fornix FA mediated - and, thus, explained - that association (95 % CI [0.002, 0.09]). Fornix FA may be an appropriate response biomarker of Mediterranean diet interventions on verbal memory in older adults.

Consideration of sex and gender in Alzheimer's disease and related disorders from a global perspective.

Sex or gender differences in the risk of Alzheimer's disease and related dementias (ADRD) differ by world region, suggesting that there are potentially modifiable risk factors for intervention. However, few epidemiological or clinical ADRD studies examine sex differences; even fewer evaluate gender in the context of ADRD risk. The goals of this perspective are to: (1) provide definitions of gender, biologic sex, and sexual orientation. and the limitations of examining these as binary variables; (2) provide an overview of what is known with regard to sex and gender differences in the risk, prevention, and diagnosis of ADRD; and (3) discuss these sex and gender differences from a global, worldwide perspective. Identifying drivers of sex and gender differences in ADRD throughout the world is a first step in developing interventions unique to each geographical and sociocultural area to reduce these inequities and to ultimately reduce global ADRD risk. HIGHLIGHTS: The burden of dementia is unevenly distributed geographically and by sex and gender. Scientific advances in genetics and biomarkers challenge beliefs that sex is binary. Discrimination against women and sex and gender minority (SGM) populations contributes to cognitive decline. Sociocultural factors lead to gender inequities in Alzheimer's disease and related dementias (ADRD) worldwide.