Assessing the contribution of the chemical exposome to neurodegenerative disease

Over the past few decades, numerous environmental chemicals from solvents to pesticides have been suggested to be involved in the development and progression of neurodegenerative diseases. Most of the evidence has accumulated from occupational or cohort studies in humans or laboratory research in animal models, with a range of chemicals being implicated. What has been missing is a systematic approach analogous to genome-wide association studies, which have identified dozens of genes involved in Alzheimer's disease, Parkinson's disease and other neurodegenerative diseases. Fortunately, it is now possible to study hundreds to thousands of chemical features under the exposome framework. This Perspective explores how advances in mass spectrometry make it possible to generate exposomic data to complement genomic data and thereby better understand neurodegenerative diseases.

Habitual coffee consumption and risk of dementia in older persons: modulation by CYP1A2 polymorphism

Higher coffee consumption has been associated with reduced dementia risk, yet with inconsistencies across studies. CYP1A2 polymorphisms, which affects caffeine metabolism, may modulate the association between coffee and the risk of dementia and Alzheimer's disease (AD). We included 5964 participants of the Three-City Study (mean age 74 years-old), free of dementia at baseline when they reported their daily coffee consumption, with available genome-wide genotyping and followed for dementia over a median of 9.0 (range 0.8-18.7) years. In Cox proportional-hazards models, the relationship between coffee consumption and dementia risk was modified by CYP1A2 polymorphism at rs762551 (p for interaction = 0.034). In multivariable-adjusted models, coffee intake was linearly associated with a decreased risk of dementia among carriers of the C allele only ("slower caffeine metabolizers"; HR for 1-cup increased [95% CI] 0.90 [0.83-0.97]), while in non-carriers ("faster caffeine metabolizers"), there was no significant association but a J-shaped trend toward a decrease in dementia risk up to 3 cups/day and increased risk beyond. Thus, compared to null intake, drinking ≥ 4 cups of coffee daily was associated with a reduced dementia risk in slower but not faster metabolizers (HR [95% CI] for ≥ 4 vs. 0 cup/day = 0.45 [0.25-0.80] and 1.32 [0.89-1.96], respectively). Results were similar when studying AD and another CYP1A2 candidate polymorphism (rs2472304), but no interaction was found with CYP1A2 rs2472297 or rs2470893. In this cohort, a linear association of coffee intake to lower dementia risk was apparent only among carriers of CYP1A2 polymorphisms predisposing to slower caffeine metabolism.

A Mediterranean Diet-Based Metabolomic Score and Cognitive Decline in Older Adults: A Case-Control Analysis Nested within the Three-City Cohort Study

SCOPE

Evidence on the Mediterranean diet (MD) and age-related cognitive decline (CD) is still inconclusive partly due to self-reported dietary assessment. The aim of the current study is to develop an MD- metabolomic score (MDMS) and investigate its association with CD in community-dwelling older adults.

METHODS AND RESULTS

This study includes participants from the Three-City Study from the Bordeaux (n = 418) and Dijon (n = 422) cohorts who are free of dementia at baseline. Repeated measures of cognition over 12 years are collected. An MDMS is designed based on serum biomarkers related to MD key food groups and using a targeted metabolomics platform. Associations with CD are investigated through conditional logistic regression (matched on age, sex, and education level) in both sample sets. The MDMS is found to be inversely associated with CD (odds ratio [OR] [95% confidence interval (CI)] = 0.90 [0.80-1.00]; p = 0.048) in the Bordeaux (discovery) cohort. Results are comparable in the Dijon (validation) cohort, with a trend toward significance (OR [95% CI] = 0.91 [0.83-1.01]; p = 0.084).

CONCLUSIONS

A greater adherence to the MD, here assessed by a serum MDMS, is associated with lower odds of CD in older adults.

Evaluation of Scores to Reflect Toxicity Impact on Quality of Life of Patients With Platinum-Resistant Ovarian Cancer: AURELIA Substudy

BACKGROUND

Current standards for toxicity reporting do not fully capture the impact of adverse events (AEs) on patients' quality of life (QoL). This study aimed to evaluate the association between toxicity and QoL by using toxicity scores that take into account CTCAE grade grouping and AE duration and cumulation.

METHODS

Analyses were performed on the AURELIA trial dataset, including 361 patients with platinum-resistant ovarian cancer treated with chemotherapy alone or with bevacizumab. Global and physical functioning QoL were issued from the EORTC QoL Questionnaire-Core 30 (QLQ-C30), collected at baseline and 8/9 and 16/18 weeks after treatment initiation. Four toxicity scores were computed: the total number of AEs, multiplied by their grade and not, and the cumulative duration of AEs, weighted by their grade and not. Each score included all AEs or only grade 3/4 nonlaboratory or treatment-related AEs. The relationship between toxicity scores and QoL was assessed through linear mixed regression.

RESULTS

We found that 171 (47.5%) and 43 (11.9%) patients experienced at least one grade 3 or 4 AE, respectively, whereas 113 (31.4%) experienced grade 2 AEs only. Physical QoL was negatively associated with all toxicity scores when computed with all grades of AEs (all P<.01), with a weaker association when treatment-related AEs were considered. Global QoL was negatively associated with toxicity scores computed with nonlaboratory all-grade AEs only (β, -3.42 to -3.13; all P<.01). Degrees of association were lower when considering the AE duration.

CONCLUSIONS

In this analysis of patients with platinum-resistant ovarian cancer, toxicity scores based on the cumulative number of AEs, modulated or not by grade, were more effective at predicting QoL changes than those based on AE duration. Toxicity impact on QoL was better reflected when grade 2 AEs were taken into account together with grade 3/4 AEs, whatever their treatment imputability, and when laboratory AEs were excluded.

Posttraumatic Stress Symptoms in Patients With Cancer During the COVID-19 Pandemic: A One-Year Longitudinal Study

BACKGROUND

Patients with cancer may be particularly vulnerable to psychological consequences of the COVID-19 pandemic. We studied the prevalence and evolution of posttraumatic stress symptoms (PTSS) in patients with cancer during the pandemic waves, and we investigated factors associated with high symptoms.

METHODS

COVIPACT is a 1-year longitudinal prospective study of French patients with solid/hematologic malignancies receiving treatment during the first nationwide lockdown. PTSS were measured every 3 months from April 2020 using the Impact of Event Scale-Revised. Patients also completed questionnaires on their quality of life, cognitive complaints, insomnia, and COVID-19 lockdown experience.

RESULTS

Longitudinal analyses involved 386 patients with at least one PTSS assessment after baseline (median age, 63 years; 76% female). Among them, 21.5% had moderate/severe PTSS during the first lockdown. The rate of patients reporting PTSS decreased at lockdown release (13.6%), increased again at second lockdown (23.2%), and slightly declined from the second release period (22.7%) to the third lockdown (17.5%). Patients were grouped into 3 trajectories of evolution. Most patients had stable low symptoms throughout the period, 6% had high baseline symptoms slowly decreasing over time, and 17.6% had moderate symptoms worsening during the second lockdown. Female sex, feeling socially isolated, worrying about COVID-19 infection, and using psychotropic drugs were associated with PTSS. PTSS were associated with impaired quality of life, sleep, and cognition.

CONCLUSIONS

Approximately one-fourth of patients with cancer experienced high and persistent PTSS over the first year of the COVID-19 pandemic and may benefit from psychological support.

CLINICALTRIALS

gov identifier: NCT04366154.

Exploration of the Gut-Brain Axis through Metabolomics Identifies Serum Propionic Acid Associated with Higher Cognitive Decline in Older Persons

The gut microbiome is involved in nutrient metabolism and produces metabolites that, via the gut−brain axis, signal to the brain and influence cognition. Human studies have so far had limited success in identifying early metabolic alterations linked to cognitive aging, likely due to limitations in metabolite coverage or follow-ups. Older persons from the Three-City population-based cohort who had not been diagnosed with dementia at the time of blood sampling were included, and repeated measures of cognition over 12 subsequent years were collected. Using a targeted metabolomics platform, we identified 72 circulating gut-derived metabolites in a case−control study on cognitive decline, nested within the cohort (discovery n = 418; validation n = 420). Higher serum levels of propionic acid, a short-chain fatty acid, were associated with increased odds of cognitive decline (OR for 1 SD = 1.40 (95% CI 1.11, 1.75) for discovery and 1.26 (1.02, 1.55) for validation). Additional analyses suggested mediation by hypercholesterolemia and diabetes. Propionic acid strongly correlated with blood glucose (r = 0.79) and with intakes of meat and cheese (r > 0.15), but not fiber (r = 0.04), suggesting a minor role of prebiotic foods per se, but a possible link to processed foods, in which propionic acid is a common preservative. The adverse impact of propionic acid on metabolism and cognition deserves further investigation.

The Plasma Oxylipin Signature Provides a Deep Phenotyping of Metabolic Syndrome Complementary to the Clinical Criteria

Metabolic syndrome (MetS) is a complex condition encompassing a constellation of cardiometabolic abnormalities. Oxylipins are a superfamily of lipid mediators regulating many cardiometabolic functions. Plasma oxylipin signature could provide a new clinical tool to enhance the phenotyping of MetS pathophysiology. A high-throughput validated mass spectrometry method, allowing for the quantitative profiling of over 130 oxylipins, was applied to identify and validate the oxylipin signature of MetS in two independent nested case/control studies involving 476 participants. We identified an oxylipin signature of MetS (coined OxyScore), including 23 oxylipins and having high performances in classification and replicability (cross-validated AUC_ROC of 89%, 95% CI: 85–93% and 78%, 95% CI: 72–85% in the Discovery and Replication studies, respectively). Correlation analysis and comparison with a classification model incorporating the MetS criteria showed that the oxylipin signature brings consistent and complementary information to the clinical criteria. Being linked with the regulation of various biological processes, the candidate oxylipins provide an integrative phenotyping of MetS regarding the activation and/or negative feedback regulation of crucial molecular pathways. This may help identify patients at higher risk of cardiometabolic diseases. The oxylipin signature of patients with metabolic syndrome enhances MetS phenotyping and may ultimately help to better stratify the risk of cardiometabolic diseases.

Post-traumatic stress disorder symptoms and associated factors in breast cancer patients during the first COVID-19 lockdown in France

Introduction

We aimed to study post-traumatic stress disorder (PTSD) symptoms in breast cancer (BC) patients during the coronavirus disease (COVID-19) pandemic.

Materials and methods

We included BC patients receiving medical treatment during the first COVID-19 lockdown in France. PTSD symptoms were evaluated using the Impact of Event Scale-Revised (IES-R) questionnaire. Quality of life [Functional Assessment of Cancer Therapy-General (FACT-G)], cognitive complaints [Functional Assessment of Cancer Therapy–Cognitive Function (FACT-Cog)], insomnia [Insomnia Severity Index (ISI)], and psychosocial experiences during lockdown were also evaluated. Multivariable logistic regression was used to identify clinical factors (from medical records) and psychosocial factors (from questionnaires) associated with PTSD symptoms.

Results

Among the 253 included BC patients (mean age: 58), 46% had metastatic cancer and 52% were treated by chemotherapy alone. COVID-19-induced adjustments in medical oncology practices were experienced by 27% of patients (mainly teleconsultations). No case of COVID-19 was reported; 23% of BC patients had PTSD symptoms. Compared to other patients, patients with PTSD symptoms had more fears relative to COVID-19 infection (83 vs. 60%, p = 0.009), had more feeling of isolation (69 vs. 41%, p = 0.003), and had more prescription or increased use of psychotropic drugs (49 vs. 20%, p = 0.001). In the multivariable model adjusted for clinical factors, fears relative to COVID-19 and increased use of psychotropic drugs were independently associated with PTSD symptoms (OR [95% CI] = 3.01 [1.20–8.44] and 3.45 [1.48–8.17], respectively). Besides, patients with PTSD symptoms had poor quality of life (QoL), and more cognitive complaints and insomnia.

Conclusion

Post-traumatic stress disorder symptoms were observed in 23% of BC patients during the first COVID-19 lockdown in France. Psychological supports are needed for patients treated during the COVID-19 pandemic.

Dietary factors and brain health

PURPOSE OF REVIEW

Nutrition is a complex exposure (i.e., the food exposome) that influences brain function and health through multiple pathways. We review recent epidemiological studies that have improved the characterization of the food exposome and brain health in humans and have revealed promising nutrition-based strategies to prevent cognitive aging.

RECENT FINDINGS

A selection of epidemiological research from the past 18 months of both observational and clinical studies is presented, with a focus on novel findings, including novel nutrient and diet patterns, diet-related approaches to rescue brain energetics defects in aging, and biomarker-based studies to decipher specific neurobiological pathways of nutrition and brain health.

SUMMARY

Although healthy diets such as the Mediterranean diet promote brain health throughout life, specific diets, such as the Mediterranean-Dietary Approaches to Stop Hypertension Intervention for Neurodegenerative Delay diet, or specific nutrients (LC n-3 polyunsaturated fatty acids, carotenoids, vitamin D, B vitamins, polyphenols) alone or in combination, may prevent cognitive aging. Diet management approaches to rescue brain energetics defects such as the Modified Mediterranean-ketogenic diet may be promising to prevent neurodegenerative diseases. Expanding research also suggests that promotion of a healthy gut microbiome through prebiotic foods may preserve the diet-gut-brain axis with aging. Future studies should explore more individualized preventive approaches through a 'precision nutrition' framework.

Apolipoprotein E and sex modulate fatty acid metabolism in a prospective observational study of cognitive decline

BACKGROUND

Fatty acids play prominent roles in brain function as they participate in structural, metabolic and signaling processes. The homeostasis of fatty acids and related pathways is known to be impaired in cognitive decline and dementia, but the relationship between these metabolic disturbances and common risk factors, namely the ɛ4 allele of the apolipoprotein E (ApoE-ɛ4) gene and sex, remains elusive.

METHODS

In order to investigate early alterations associated with cognitive decline in the fatty acid-related serum metabolome, we here applied targeted metabolomics analysis on a nested case-control study (N=368), part of a prospective population cohort on dementia.

RESULTS

When considering the entire study population, circulating levels of free fatty acids, acyl-carnitines and pantothenic acid were found to be increased among those participants who had greater odds of cognitive decline over a 12-year follow-up. Interestingly, stratified analyses indicated that these metabolomic alterations were specific for ApoE-ɛ4 non-carriers and women.

CONCLUSIONS

Altogether, our results highlight that the regulation of fatty acids and related metabolic pathways during ageing and cognitive decline depends on complex inter-relationships between the ApoE-ε4 genotype and sex. A better understanding of the ApoE-ɛ4 and sex dependent modulation of metabolism is essential to elucidate the individual variability in the onset of cognitive decline, which would help develop personalized therapeutic approaches.

Association of a MIND Diet with Brain Structure and Dementia in a French Population

BACKGROUND

Adherence to the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet, which combines higher consumption of vegetables, berries, nuts, whole grains, olive oil, fish, beans and poultry, with lower consumption of meat, sugars and saturated fats, is a promising strategy to prevent dementia. However, evidence in populations with non-US food culture, especially from Europe, is limited.

OBJECTIVES

To evaluate the association of a French-adapted MIND diet score with gray matter volumes, white matter microstructure and incident dementia.

DESIGN AND SETTING

This longitudinal study included participants from the population-based Three-City Bordeaux cohort (≥65 years), with a follow-up from June 2001 to February 2018.

PARTICIPANTS

Dementia-free participants at dietary assessment, in 2001-2002, who underwent systematic detection of incident dementia (over up to 7 visits). A subset of the cohort was included in an ancillary MRI study in 2010-2011.

MEASUREMENTS

A French-adapted MIND diet score (range, 0-15) was computed from a 148-item Food Frequency Questionnaire and a 24-hour recall administered at home. Incident dementia and its subtypes were adjudicated by an expert committee; and gray matter volumes and white matter microstructure were assessed by 3D-T1 MRI and diffusion-MRI.

RESULTS

Among 1,412 participants (mean age, 75.8 [SD, 4.8]; 63% women), followed for a median of 9.7 years (maximum 16.3 years), 356 (25.2%) developed incident dementia. In multivariable-adjusted Cox model, a higher French MIND diet score was associated with lower risks of dementia and AD (hazard ratios for 1-point of score = 0.89 [95% confidence interval, 0.83-0.95] and 0.88 [0.81-0.96], respectively). In Tract-Based Spatial Statistics analysis of 175 participants included in the MRI sub-study, a higher MIND diet score was associated with lower diffusivity values in the splenium of the corpus callosum (P < .05 after Family-Wise Error-correction). In contrast, there was no significant association of the adapted MIND diet score with gray matter volumes in Voxel-Based Morphometry analysis.

CONCLUSION

In this cohort of French older adults, higher adherence to the French MIND diet was associated with a lower dementia risk and with preserved white matter microstructure. These results provide further evidence for a role of the MIND diet in the prevention of dementia.

Impaired hippocampal neurogenesis in vitro is modulated by dietary-related endogenous factors and associated with depression in a longitudinal ageing cohort study

Environmental factors like diet have been linked to depression and/or relapse risk in later life. This could be partially driven by the food metabolome, which communicates with the brain via the circulatory system and interacts with hippocampal neurogenesis (HN), a form of brain plasticity implicated in depression aetiology. Despite the associations between HN, diet and depression, human data further substantiating this hypothesis are largely missing. Here, we used an in vitro model of HN to test the effects of serum samples from a longitudinal ageing cohort of 373 participants, with or without depressive symptomology. 1% participant serum was applied to human fetal hippocampal progenitor cells, and changes in HN markers were related to the occurrence of depressive symptoms across a 12-year period. Key nutritional, metabolomic and lipidomic biomarkers (extracted from participant plasma and serum) were subsequently tested for their ability to modulate HN. In our assay, we found that reduced cell death and increased neuronal differentiation were associated with later life depressive symptomatology. Additionally, we found impairments in neuronal cell morphology in cells treated with serum from participants experiencing recurrent depressive symptoms across the 12-year period. Interestingly, we found that increased neuronal differentiation was modulated by increased serum levels of metabolite butyrylcarnitine and decreased glycerophospholipid, PC35:1(16:0/19:1), levels - both of which are closely linked to diet - all in the context of depressive symptomology. These findings potentially suggest that diet and altered HN could subsequently shape the trajectory of late-life depressive symptomology.

A Biological Index to Screen Multi-Micronutrient Deficiencies Associated with the Risk to Develop Dementia in Older Persons from the Community

BACKGROUND

Low blood status in several nutritional compounds, including long-chain omega-3 fatty acids (LC n-3 PUFA), carotenoids, and vitamin D, have been associated with a higher risk to develop dementia. Nutritional deficiencies may potentiate each other regarding dementia risk; yet the association of multiple nutritional deficiencies with dementia has been little explored.

OBJECTIVE

To develop an index of micronutritional biological status (MNBS) for the screening of multi-micronutritional deficiencies associated with the risk of dementia in a prospective population-based cohort of older persons.

METHODS

We included participants from the Bordeaux Three-City study, who were free of dementia at baseline, had blood measurements of LC n-3 PUFA, carotenoids, and 25(OH)D, and who were followed for up to 18 years for dementia. We used penalized splines in Cox models to model dose-response relationships of each nutritional component with the risk of dementia and construct a risk index.

RESULTS

629 participants with an average age of 73.1 years were included in the study. Each increase of 1 SD of the MNBS index was associated with a 46%higher risk of dementia (HR = 1.46, 95%CI 1.23; 1.73). Participants with highest index ([mean+1SD; max]) had a 4-fold increased risk of dementia compared with participants with a low index ([min; mean-1SD]) (HR = 4.17, 95%CI 2.30; 7.57).

CONCLUSION

This index of assessment of micronutritional biological status is a practical tool that may help identify populations with inadequate nutritional status, screen eligible individuals for nutritional prevention in primary care, or for supplementation in preventive trials of dementia.

Personalized nutrition for dementia prevention

The role of nutrition has been investigated for decades under the assumption of one-size-fits-all. Yet there is heterogeneity in metabolic and neurobiological responses to diet. Thus a more personalized approach may better fit biological reality and have increased efficacy to prevent dementia. Personalized nutrition builds on the food exposome, defined as the history of diet-related exposures over the lifetime, and on its interactions with the genome and other biological characteristics (eg, metabolism, the microbiome) to shape health. We review current advances of personalized nutrition in dementia research. We discuss key questions, success milestones, and future roadmap from observational epidemiology to clinical studies through basic science. A personalized nutrition approach based on the best prescription for the most appropriate target population in the most relevant time-window has the potential to strengthen dementia-prevention efforts.

Food and Microbiota Metabolites Associate with Cognitive Decline in Older Subjects: A 12-Year Prospective Study

SCOPE

Diet is considered an important modulator of cognitive decline and dementia, but the available evidence is, however, still fragmented and often inconsistent.

METHODS AND RESULTS

The article studies the long-term prospective Three-City Cohort, which consists of two separate nested case-control sample sets from different geographic regions (Bordeaux, n = 418; Dijon, n = 424). Cognitive decline is evaluated through five neuropsychological tests (Mini-Mental State Examination, Benton Visual Retention Test, Isaac's Set Test, Trail-Making Test part A, and Trail-Making Test part B). The food-related and microbiota-derived circulating metabolome is studied in participants free of dementia at baseline, by subjecting serum samples to large-scale quantitative metabolomics analysis. A protective association is found between metabolites derived from cocoa, coffee, mushrooms, red wine, the microbial metabolism of polyphenol-rich foods, and cognitive decline, as well as a negative association with metabolites related to unhealthy dietary components, such as artificial sweeteners and alcohol.

CONCLUSION

These results provide insight into the early metabolic events that are associated with the later risk to develop cognitive decline within the crosstalk between diet, gut microbiota and the endogenous metabolism, which can help identify potential targets for preventive and therapeutic strategies to preserve cognitive health.

The serum metabolome mediates the concert of diet, exercise, and neurogenesis, determining the risk for cognitive decline and dementia

INTRODUCTION

Diet and exercise influence the risk of cognitive decline (CD) and dementia through the food metabolome and exercise-triggered endogenous factors, which use the blood as a vehicle to communicate with the brain. These factors might act in concert with hippocampal neurogenesis (HN) to shape CD and dementia.

METHODS

Using an in vitro neurogenesis assay, we examined the effects of serum samples from a longitudinal cohort (n = 418) on proxy HN readouts and their association with future CD and dementia across a 12-year period.

RESULTS

Altered apoptosis and reduced hippocampal progenitor cell integrity were associated with exercise and diet and predicted subsequent CD and dementia. The effects of exercise and diet on CD specifically were mediated by apoptosis.

DISCUSSION

Diet and exercise might influence neurogenesis long before the onset of CD and dementia. Alterations in HN could signify the start of the pathological process and potentially represent biomarkers for CD and dementia.

Post-traumatic stress symptomatology and adjustment of medical oncology practice during the COVID-19 pandemic among adult patients with cancer in a day care hospital

Background

The COVID‐19 pandemic may induce post‐traumatic stress disorder (PTSD) symptoms among patients with cancer, who also face adaptations to their treatment. The authors assessed the occurrence of PTSD symptoms, investigated pandemic‐induced adjustments in medical oncology practice in patients with cancer, and explored risk factors for PTSD and the association between PTSD symptoms, insomnia, and quality of life (QoL).

Methods

This prospective French study was conducted in patients with solid/hematologic tumors who were receiving medical treatment in the day care departments of 2 cancer centers during the lockdown. Adjustments to medical oncology practice were collected from medical records. PTSD (measured using the Impact of Event Scale‐Revised), insomnia (measured using the Insomnia Severity Index), QoL (measured using the Functional Assessment of Cancer Therapy‐General instrument), and cognitive complaints (measured using the Functional Assessment of Cancer Therapy–Cognitive Function instrument) were collected through validated questionnaires.

Results

Clinical data and questionnaires were available for 734 and 576 patients, respectively. The median patient age was 64 years, and 69% of patients were women. Twenty‐one percent of patients had PTSD. Twenty‐seven percent (95% CI, 23%‐30%) had an adjustment in their medical oncology program, including adjournments (29%), treatment interruptions (16%), modified treatment plans (27%), or adapted monitoring (27%). Women and patients experiencing an adjustment in oncology practice had a higher odds of PTSD (odds ratio= 2.10 [95% CI, 1.07‐4.14] and 1.65 [95% CI, 1.03‐2.63]; P < .05). PTSD symptoms were correlated with worse scores for QoL, cognition, and insomnia.

Conclusions

Twenty‐one percent of patients with cancer experienced PTSD symptoms associated with poor QoL during the first COVID‐19–induced lockdown. Medical oncology practice was adjusted in approximately one‐quarter of patients and was associated with the occurrence of PTSD symptoms. Psychosocial support should be offered in cancer centers to promote emotional resilience and avoid PTSD symptoms in patients.

Post‐traumatic stress disorder symptomatology occurred in 21% of patients with cancer during the first lockdown due to COVID‐19, was more frequent among women, and was associated with adjustment in medical oncology treatments. Caregivers should pay special attention to the psychological needs of patients with cancer to prevent or manage post‐traumatic stress disorder symptoms.

Vitamin D Intake and Brain Cortical Thickness in Community-Dwelling Overweight Older Adults: A Cross-Sectional Study

BACKGROUND

Vitamin D is critical to brain health and a promising candidate to prevent cognitive decline and onset of Alzheimer disease (AD), although the underlying brain mechanisms are unclear.

OBJECTIVES

This study aimed to determine the association between vitamin D intake and brain cortical thickness in older adults.

METHODS

This was a cross-sectional investigation of 263 cognitively unimpaired participants, aged 65 y and older, participating in the MIND (Mediterranean-DASH Intervention for Neurodegenerative Delay) trial (an ongoing study testing the effects of a 3-y diet intervention on cognitive decline). Vitamin D intake, from diet and supplements, was ascertained from an FFQ. Linear regression analysis, adjusted for age, sex, race, education, income, cognitive and physical activities, and cardiovascular disease risk factors, was used to determine the association between vitamin D intake and cortical thickness of the whole brain, lobes, and AD signature.

RESULTS

Total vitamin D intake was associated with cortical thickness of the temporal lobe and AD signature. Compared with individuals in the lowest quartile of total vitamin D intake [median: 140 international units (IU)/d], those in the highest quartile (median: 1439 IU/d) had a 0.038-mm (95% CI: 0.006, 0.069 mm) thicker temporal lobe and 0.041-mm (95% CI: 0.012, 0.070 mm) thicker AD signature. Most vitamin D intake was from supplements, and supplemental intake was also associated with cortical thickness. Compared with those who used no supplement, individuals taking 800-1000 IU/d and >1000 IU/d of supplemental vitamin D had a 0.039-mm (95% CI: 0.013, 0.066 mm) and 0.047-mm (95% CI: 0.013, 0.081 mm) thicker temporal lobe and a 0.037-mm (95% CI: 0.013, 0.061 mm) and 0.046-mm (95% CI: 0.015, 0.077 mm) thicker AD signature, respectively. Dietary vitamin D was not related to brain cortical thickness in our sample.

CONCLUSIONS

In cognitively unimpaired older adults, total and supplemental vitamin D intakes were associated with cortical thickness in regions vulnerable to AD.This trial was registered at clinicaltrials.gov as NCT02817074.

Evolution of post-traumatic stress disorder and patient reported-outcomes during the COVID-19 pandemic among cancer patients of the French longitudinal COVIPACT study

12123

Background: Sudden COVID-19 pandemic has enforced social restrictions across the globe, including social distancing, curfews and total lockdowns, which persist in many parts of the world. Beyond these measures, cancer patients have faced up to the threat of the risk of severe COVID-19 infections and the adaptations of medical oncology practices, with potential impact on their psychological well-being. We aimed to follow Post-Traumatic Stress Disorder (PTSD) symptoms and other Patient-Reported Outcomes (PROs) over this period among cancer patients from the French COVIPACT study. Methods: The COVIPACT study (NCT04366154) included patients with solid/hematologic malignancy receiving medical treatment during the first lockdown in outpatient departments of two cancer centers. Patients were asked to fulfill validated questionnaires on PTSD symptoms (IES-R), insomnia (ISI), quality of life (FACT-G) and cognition (FACT-Cog) at baseline (M0, first lockdown, Apr/May 2020), 3 months (M3, post-lockdown, Jul/Aug 2020) and 6 months (M6, second lockdown, Oct/Nov 2020). PTSD was defined as an IES-R score ≥33 and moderate/severe insomnia as an ISI score ≥15. Higher values on the FACT-G (range 0-108) and FACT-Cog (PCI subscale range 0-72) indicated better quality of life and cognition, respectively. Changes in PROs over time were assessed using mixed models for repeated measures. Results: Among the 734 patients included in COVIPACT, 579, 347 and 328 completed the questionnaires at M0, M3 and M6, respectively: median age, 64 years, 72% women, 59% metastatic status. Patients were mostly treated for breast (44%), lung, head and neck (20%), digestive (16%) and gynecologic cancers (11%). We observed a J-shaped evolution of PTSD over time, affecting 21.2% of patients during the first lockdown, 13.6% the post-lockdown and 23.6% during the second lockdown (p for time < 0.001). Moreover, patients reported linear deterioration of cognitive function over follow-up (p < 0.001). No change was observed in any dimension of quality of life (p for time = 0.06). 24.3%, 27.1% and 28.1% of the patients reported insomnia at M0,M3 and M6 (p for time = 0.35). At each time, PTSD was associated with more insomnia, worst quality of life and cognitive complain. At all the times, ≥50% of patients with PTSD reported insomnia compared to ≤23% in non-PTSD patients (p < 0.001). In addition, there was a clinically significant difference of ≥16 points on the FACT-G and ≥8 points on the FACT-Cog PCI between PTSD and non-PTSD patients (p < 0.001) at the all times. Conclusions: More than 20% of patients have developed PTSD during the different periods of lockdown, with strong association with poor quality of life, cognitive complain and insomnia. Psychosocial support promoting emotional resilience should be largely offered to cancer patients to prevent and/or reduce PTSD. Clinical trial information: NCT04366154.

Tall 3-dwarfs: oxymoron or opportunity to increase grain yield in sorghum?

Plant height was positively correlated with grain yield across a large set of 3-dwarf sorghum hybrids and production environments in north-eastern Australia. In industrialised countries, plant breeders tend to select for short plant stature in cereals like wheat, barley and rice, but also grain sorghum. This is mainly to prevent stalk lodging and to allow for machine harvesting. However, this counteracts an intrinsic positive relationship between plant height and yield potential often observed in cereals. We used data from multi-environment breeding trials comprising large sets of female sorghum lines from a range of pedigrees in hybrid combination with five different male testers. The hybrids were grown in 22 different rainfed environments in north-eastern Australia, which allowed us to thoroughly examine the relationship between plant height and yield across a range of productivity levels. Covariate analysis showed that in 38 out of the 90 tested relationships, grain yield was significantly (p < 0.05) positively and in only one case significantly negatively associated with plant height. This strong positive association between the traits was supported by the observation that 87% of the effects were either positive or zero. The effects of height on yield ranged from a decrease of 0.015 t ha^-1 to an increase of 0.057 t ha^-1 cm^-1. The majority of the negative effects were observed in low-yielding trials and the positive effect of height tended to increase with increasing mean trial yield. Opportunities to increase yield potential by selecting for slightly taller sorghum hybrids therefore need to be explored in context with the target environments and in combination with other means to control the risks of lodging.

Early signature in the blood lipidome associated with subsequent cognitive decline in the elderly: A case-control analysis nested within the Three-City cohort study

BACKGROUND

Brain lipid metabolism appears critical for cognitive aging, but whether alterations in the lipidome relate to cognitive decline remains unclear at the system level.

METHODS

We studied participants from the Three-City study, a multicentric cohort of older persons, free of dementia at time of blood sampling, and who provided repeated measures of cognition over 12 subsequent years. We measured 189 serum lipids from 13 lipid classes using shotgun lipidomics in a case-control sample on cognitive decline (matched on age, sex and level of education) nested within the Bordeaux study center (discovery, n = 418). Associations with cognitive decline were investigated using bootstrapped penalized regression, and tested for validation in the Dijon study center (validation, n = 314).

FINDINGS

Among 17 lipids identified in the discovery stage, lower levels of the triglyceride TAG50:5, and of four membrane lipids (sphingomyelin SM40:2,2, phosphatidylethanolamine PE38:5(18:1/20:4), ether-phosphatidylethanolamine PEO34:3(16:1/18:2), and ether-phosphatidylcholine PCO34:1(16:1/18:0)), and higher levels of PCO32:0(16:0/16:0), were associated with greater odds of cognitive decline, and replicated in our validation sample.

INTERPRETATION

These findings indicate that in the blood lipidome of non-demented older persons, a specific profile of lipids involved in membrane fluidity, myelination, and lipid rafts, is associated with subsequent cognitive decline.

FUNDING

The complete list of funders is available at the end of the manuscript, in the Acknowledgement section.

Caffeine Compromises Proliferation of Human Hippocampal Progenitor Cells

The age-associated reduction in the proliferation of neural stem cells (NSCs) has been associated with cognitive decline. Numerous factors have been shown to modulate this process, including dietary components. Frequent consumption of caffeine has been correlated with an increased risk of cognitive decline, but further evidence of a negative effect on hippocampal progenitor proliferation is limited to animal models. Here, we used a human hippocampal progenitor cell line to investigate the effects of caffeine on hippocampal progenitor integrity and proliferation specifically. The effects of five caffeine concentrations (0 mM = control, 0.1 mM ∼ 150 mg, 0.25 mM ∼ 400 mg, 0.5 mM ∼ 750 mg, and 1.0 mM ∼ 1500 mg) were measured following acute (1 day) and repeated (3 days) exposure. Immunocytochemistry was used to quantify hippocampal progenitor integrity (i.e., SOX2- and Nestin-positive cells), proliferation (i.e., Ki67-positive cells), cell count (i.e., DAPI-positive cells), and apoptosis (i.e., CC3-positive cells). We found that progenitor integrity was significantly reduced in supraphysiological caffeine conditions (i.e., 1.0 mM ∼ 1500 mg), but relative to the lowest caffeine condition (i.e., 0.1 mM ∼ 150 mg) only. Moreover, repeated exposure to supraphysiological caffeine concentrations (i.e., 1.0 mM ∼ 1500 mg) was found to affect proliferation, significantly reducing % Ki67-positive cells relative to control and lower caffeine dose conditions (i.e., 0.1 mM ∼ 150 mg and 0.25 mM ∼ 400 mg). Caffeine treatment did not influence apoptosis and there were no significant differences in any measure between lower doses of caffeine (i.e., 0.1 mM, 0.25 mM, 0.5 mM) – representative of daily human caffeine intake – and control conditions. Our study demonstrates that dietary components such as caffeine can influence NSC integrity and proliferation and may be indicative of a mechanism by which diet affects cognitive outcomes.

Using network science tools to identify novel diet patterns in prodromal dementia

OBJECTIVE

To use network science to model complex diet relationships a decade before onset of dementia in a large French cohort, the 3-City Bordeaux study.

METHODS

We identified cases of dementia incident to the baseline food frequency questionnaire over 12 years of follow-up. For each case, we randomly selected 2 controls among individuals at risk at the age at case diagnosis and matched for age at diet assessment, sex, education, and season of the survey. We inferred food networks in both cases and controls using mutual information, a measure to detect nonlinear associations, and compared food consumption patterns between groups.

RESULTS

In the nested case-control study, the mean (SD) duration of follow-up and number of visits were 5.0 (2.5) vs 4.9 (2.6) years and 4.1 (1.0) vs 4.4 (0.9) for cases (n = 209) vs controls (n = 418), respectively. While there were few differences in simple, average food intakes, food networks differed substantially between cases and controls. The network in cases was focused and characterized by charcuterie as the main hub, with connections to foods typical of French southwestern diet and snack foods. In contrast, the network of controls included several disconnected subnetworks reflecting diverse and healthier food choices.

CONCLUSION

How foods are consumed (and not only the quantity consumed) may be important for dementia prevention. Differences in predementia diet networks, suggesting worse eating habits toward charcuterie and snacking, were evident years before diagnosis in this cohort. Network methods, which are designed to model complex systems, may advance our understanding of risk factors for dementia.

Diet-Related Metabolites Associated with Cognitive Decline Revealed by Untargeted Metabolomics in a Prospective Cohort

Scope

Untargeted metabolomics may reveal preventive targets in cognitive aging, including within the food metabolome.

Methods and results

A case‐control study nested in the prospective Three‐City study includes participants aged ≥65 years and initially free of dementia. A total of 209 cases of cognitive decline and 209 controls (matched for age, gender, education) with slower cognitive decline over up to 12 years are contrasted. Using untargeted metabolomics and bootstrap‐enhanced penalized regression, a baseline serum signature of 22 metabolites associated with subsequent cognitive decline is identified. The signature includes three coffee metabolites, a biomarker of citrus intake, a cocoa metabolite, two metabolites putatively derived from fish and wine, three medium‐chain acylcarnitines, glycodeoxycholic acid, lysoPC(18:3), trimethyllysine, glucose, cortisol, creatinine, and arginine. Adding the 22 metabolites to a reference predictive model for cognitive decline (conditioned on age, gender, education and including ApoE‐ε4, diabetes, BMI, and number of medications) substantially increases the predictive performance: cross‐validated Area Under the Receiver Operating Curve = 75% [95% CI 70–80%] compared to 62% [95% CI 56–67%].

Conclusions

The untargeted metabolomics study supports a protective role of specific foods (e.g., coffee, cocoa, fish) and various alterations in the endogenous metabolism responsive to diet in cognitive aging.

Pattern of polyphenol intake and the long-term risk of dementia in older persons

OBJECTIVE

To investigate the optimal combination of dietary polyphenols associated with the long-term risk of dementia in a large prospective French cohort of older persons, the Three-City (3C) Study.

METHODS

We included 1,329 older adults without dementia from the 3C study with assessment of intake of 26 polyphenol subclasses who were followed up for 12 years for dementia. Using partial least squares for Cox models, we identified a pattern of polyphenol intake associated with dementia risk.

RESULTS

The pattern combined several flavonoids (dihydroflavonols, anthocyanins, isoflavonoids, flavanones), stilbenes (including resveratrol), lignans, and other subclasses (hydroxybenzaldehydes, naphthoquinones, furanocoumarins). Compared with participants in the lower quintile of pattern score, those in the higher quintile had a 50% lower risk of dementia (95% confidence interval 20%-68%, p for trend <0.01) in multivariate models.

CONCLUSIONS

In this French cohort, a polyphenol pattern provided by a diet containing specific plant products (nuts, citrus, berries, leafy vegetables, soy, cereals, olive oil) accompanied by red wine and tea was associated with lower dementia risk.

Dietary B Vitamins and a 10-Year Risk of Dementia in Older Persons

B vitamins may lower the risk of dementia, yet epidemiological findings, mostly from countries with folic acid fortification, have remained inconsistent. We evaluated in a large French cohort of older persons the associations between dietary B vitamins and long-term incident dementia. We included 1321 participants from the Three-City Study who completed a 24 h dietary recall, were free of dementia at the time of diet assessment, and were followed for an average of 7.4 years. In Cox proportional hazards models adjusted for multiple potential confounders, including overall diet quality, higher intake of folate was inversely associated with the risk of dementia (p for trend = 0.02), with an approximately 50% lower risk for individuals in the highest compared to the lowest quintile of folate (HR = 0.47; 95% CI 0.28; 0.81). No association was found for vitamins B6 and B12. In conclusion, in a large French cohort with a relatively low baseline folate status (average intake = 278 µg/day), higher folate intakes were associated with a decreased risk of dementia.