'Food for Thought'-The Relationship between Diet and Cognition in Breast and Colorectal Cancer Survivors: A Feasibility Study

Cognitive impairment following breast cancer treatments: an umbrella review

OBJECTIVES

Cancer-related cognitive impairment (CRCI) refers to a cognitive decline associated with cancer or its treatments. While research into CRCI is expanding, evidence remains scattered due to differences in study designs, methodologies, and definitions. The present umbrella review aims to provide a comprehensive overview of the current evidence regarding the impact of different breast cancer therapies on cognitive functioning, with a particular focus on the interplay among objective cognitive deficits (ie, measured with standardized tests), subjective cognitive concerns, (ie, self-reported), and other mediating psycho-physical factors.

METHODS

The search was made in Pubmed, Embase, and Scopus for articles published until July 2023, following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analysis protocol.

RESULTS

Chemotherapy and endocrine therapy appear consistently associated with CRCI in patients with breast cancer, primarily affecting memory, attention/concentration, executive functioning, and processing speed. Subjective cognitive concerns were often found weakly or not associated with neuropsychological test results, while overall CRCI seemed consistently associated with psychological distress, fatigue, sleep quality, and inflammatory and biological factors.

CONCLUSION

Current evidence suggests that CRCI is common after chemotherapy and endocrine therapy for breast cancer. However, heterogeneity in study designs and the scarcity of studies on more recent treatments such as targeted therapies and immunotherapies, highlight the need for more systematic and harmonized studies, possibly taking into account the complex and multifactorial etiology of CRCI. This may provide valuable insights into CRCI's underlying mechanisms and potential new ways to treat it.

Omega-3 index, cardiorespiratory fitness, and cognitive function in mid-age and older adults

Higher levels of omega-3 fatty acids in red blood cell membranes (omega-3 index or O3I) and cardiorespiratory fitness (CRF) are each associated with reduced cognitive impairment, but little research has examined the relationship between O3I and cognitive function while accounting for CRF. We analyzed cross-sectional data from 5,464 healthy men and women aged 55-85 years who had preventive medical examinations between 2009 and 2023. Primary exposures included O3I (<4.0%, 4.0-7.9%, or ≥ 8.0%) and age- and sex-based CRF quintile (1 = low, 2-3 = moderate, 4-5 = high). Cognitive impairment was defined as a Montreal Cognitive Assessment score of ≤ 25. We used Poisson regression to estimate relative risks (RR) of cognitive impairment, controlling for covariates. O3I < 4% was associated with increased cognitive impairment relative to ≥ 8.0% (RR, 1.21; 95% CI, 1.01-1.44) in a partially adjusted model. This association did not remain statistically significant in the fully adjusted model which included CRF. Low versus high CRF was associated with cognitive impairment (RR, 1.28; 95% CI, 1.07-1.53), independent of O3I and clinical biomarkers. The interaction between CRF and O3I was not significant (P = 0.8). In joint association analysis, risk of cognitive impairment was elevated with lower omega-3 index or CRF or both. Additional research is needed to fully understand the association between O3I and cognitive function at varying CRF levels.

Associations of erythrocyte omega-3 fatty acids with cognition, brain imaging and biomarkers in the Alzheimer's disease neuroimaging initiative: cross-sectional and longitudinal retrospective analyses

BACKGROUND

The association between omega-3 (ω-3) PUFAs and cognition, brain imaging and biomarkers is still not fully established.

OBJECTIVES

The aim was to analyze the cross-sectional and retrospective longitudinal associations between erythrocyte ω-3 index and cognition, brain imaging, and biomarkers among older adults.

METHODS

A total of 832 Alzheimer's Disease Neuroimaging Initiative 3 (ADNI-3) participants, with a mean (SD) age of 74.0 (7.9) y, 50.8% female, 55.9% cognitively normal, 32.7% with mild cognitive impairment, and 11.4% with Alzheimer disease (AD) were included. A low ω-3 index (%EPA + %DHA) was defined as the lowest quartile (≤3.70%). Cognitive tests [composite score, AD Assessment Scale Cognitive (ADAS-Cog), Wechsler Memory Scale (WMS), Trail Making Test, Category Fluency, Mini-Mental State Examination, Montreal Cognitive Assessment] and brain variables [hippocampal volume, white matter hyperintensities (WMHs), positron emission tomography (PET) amyloid-β (Aβ) and tau] were considered as outcomes in regression models.

RESULTS

Low ω-3 index was not associated with cognition, hippocampal, and WMH volume or brain Aβ and tau after adjustment for demographics, ApoEε4, cardiovascular disease, BMI, and total intracranial volume in the cross-sectional analysis. In the retrospective analysis, low ω-3 index was associated with greater Aβ accumulation (adjusted β = 0.02; 95% CI: 0.01, 0.03; P = 0.003). The composite cognitive score did not differ between groups; however, low ω-3 index was significantly associated with greater WMS-delayed recall cognitive decline (adjusted β = -1.18; 95% CI: -2.16, -0.19; P = 0.019), but unexpectedly lower total ADAS-Cog cognitive decline. Low ω-3 index was cross-sectionally associated with lower WMS performance (adjusted β = -1.81, SE = 0.73, P = 0.014) and higher tau accumulation among ApoE ε4 carriers.

CONCLUSIONS

Longitudinally, low ω-3 index was associated with greater Aβ accumulation and WMS cognitive decline but unexpectedly with lower total ADAS-Cog cognitive decline. Although no associations were cross-sectionally found in the whole population, low ω-3 index was associated with lower WMS cognition and higher tau accumulation among ApoE ε4 carriers. The Alzheimer's Disease Neuroimaging Initiative (ADNI) is registered at clinicaltrials.gov as NCT00106899.