Christophe Tzourio

University of Bordeaux · Bordeaux Population Health Research Center (BPH)

Identifying circulating proteins associated with cognitive function may point to biomarkers and molecular process of cognitive impairment. Few studies have investigated the association between circulating proteins and cognitive function. We identify 246 protein measures quantified by the SomaScan assay as associated with cognitive function (p < 4.9...

Many studies suggest a relationship between excessive daytime sleepiness (EDS) and dementia incidence, but the underlying mechanisms remain uncertain. The study aimed to investigate the role of cardiovascular burden in the relationship between EDS and dementia incidence over a 12‐year follow‐up in community‐dwelling older adults. We performed analy...

Anxiety is a diffuse condition that can range from mild to more severe manifestations, including proper anxiety disorders. Specific sensitive periods such as adolescence and young adulthood are particularly vulnerable to anxious states and may favour the onset of future anxiety disorders. Until now, neuroanatomical research on anxiety has focused m...

During the past decade, cognitive neuroscience has been calling for population diversity to address the challenge of validity and generalizability, ushering in a new era of population neuroscience. The developing Chinese Color Nest Project (devCCNP, 2013–2022), the first ten-year stage of the lifespan CCNP (2013–2032), is a two-stages project focus...

Importance: There is increasing recognition that vascular disease, which can be treated, is a key contributor to dementia risk. However, the contribution of specific markers of vascular disease is unclear and, as a consequence, optimal prevention strategies remain unclear. Objective: To disentangle the causal relation of several key vascular traits...

Given the anatomical and functional similarities between the retina and the brain, the retina could be a "window" for viewing brain structures. We investigated the association between retinal nerve fiber layers (peripapillary retinal nerve fiber layer, ppRNFL; macular ganglion cell-inner plexiform layer, GC-IPL; and macular ganglion cell complex, G...

Given the high incidence of cardio and cerebrovascular diseases (CVD), and its association with morbidity and mortality, its prevention is a major public health issue. A high level of blood pressure is a well-known risk factor for these events and an increasing number of studies suggest that blood pressure variability may also be an independent ris...

This research explores the effects of drowsiness on variability in functional connectivity (FC) during resting-state functional magnetic resonance imaging. The study utilized a cohort of students (MRi-Share) and classified individuals into drowsy (N=68), alert (N=96), and mixed/undetermined states based on observed respiratory oscillations. Five di...

Background Environmental factors, such as nutrition, influence brain physiology and health throughout the life course. While research has focused on the extremes of the age spectrum, less is known about early adulthood, yet a critical period for the consolidation of brain maturation and the building of adult behaviors. Nutrition may impact late mat...

Perivascular space (PVS) burden is an emerging, poorly understood, magnetic resonance imaging marker of cerebral small vessel disease, a leading cause of stroke and dementia. Genome-wide association studies in up to 40,095 participants (18 population-based cohorts, 66.3 ± 8.6 yr, 96.9% European ancestry) revealed 24 genome-wide significant PVS risk...

To examine the relationship between adverse childhood experiences (ACEs) and Attention-deficit Hyperactivity Disorder (ADHD) among college students. We investigated the association between ACEs and ADHD symptoms among French college students enrolled in the i-Share cohort using multivariate logistic regression models. The sample comprised of 1062 p...

Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1–6 . Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural an...

The epidemiological and societal burden of dementia is expected to increase in the coming decades due to the world population aging. In this context, the evaluation of the potential impact of intervention scenarios aiming at reducing the prevalence of dementia risk factors is an active area of research. However, such studies must account for the as...

White matter hyperintensities (WMH) are well-established markers of cerebral small vessel disease (cSVD), and are associated with an increased risk of stroke, dementia, and mortality. Although their prevalence increases with age, small and punctate WMHs have been reported with surprisingly high frequency even in young, neurologically asymptomatic a...

Sleep complaints and cannabis use are common among University students and are related to detrimental effects on health. The aim of this study was to explore their association. This cross-sectional study based on the i-Share e-cohort included French students between 18 and 30 years old (n = 14,787). Frequency of cannabis use was categorized into da...

Background: The long-term effects of traumatic brain injury (TBI) with loss of consciousness (LOC) on magnetic resonance imaging (MRI) markers of brain health and on dementia risk are still debated. Objective: To investigate the associations of history of TBI with LOC with incident dementia and neuroimaging markers of brain structure and small v...

Visit-to-visit blood pressure variability (BPV) has been identified in several recent studies as a risk factor for stroke, independently of the level of BP. If true, this finding could help to identify patients at higher risk of stroke and to develop new preventive strategies. However, studies on BPV are exposed to important methodological challeng...

Cerebral small vessel disease (cSVD) is a leading cause of vascular cognitive impairment and dementia. Mounting evidence suggests that early life factors contribute to cSVD. Genetic risk loci for white matter hyperintensities (WMH), the most common MRI‐marker of cSVD in older age, were recently found to show strong associations with white matter mi...

Perivascular space (PVS) burden is an emerging MRI‐marker of cerebral small vessel disease (cSVD), a leading cause of stroke and dementia. Underlying mechanisms of PVS are unknown. PVS are thought to be related to the glymphatic system, involved in brain clearance of molecules such as amyloid beta. We aimed to decipher the genetic underpinnings of...

Background: The use of the internet to look for information about vaccines has skyrocketed in the last years, especially with the COVID-19 pandemic. Digital vaccine literacy (DVL) refers to understanding, trust, appraisal, and application of vaccine-related information online. Objective: This study aims to develop a tool measuring DVL and assess i...

Observational studies indicate U‐shaped associations of blood pressure (BP) and incident dementia in older age, but randomised controlled trials of BP lowering treatment show mixed results on this outcome in hypertensive patients. We undertook a pooled individual participant data analysis of five seminal double‐blind placebo‐controlled randomised t...

Aims Observational studies indicate U-shaped associations of blood pressure (BP) and incident dementia in older age, but randomized controlled trials of BP-lowering treatment show mixed results on this outcome in hypertensive patients. A pooled individual participant data analysis of five seminal randomized double-blind placebo-controlled trials wa...

Restrictive measures during the COVID-19 epidemic have led to increased levels of loneliness, especially among university students, although the influence on suicidal thoughts remains unclear. In this cross-sectional study of 1913 French university students, those with the highest level of loneliness had a fourfold increased risk of suicidal though...

Autoantibodies neutralizing type I interferons (IFNs) can underlie critical COVID-19 pneumonia and yellow fever vaccine disease. We report here on 13 patients harboring autoantibodies neutralizing IFN-α2 alone (five patients) or with IFN-ω (eight patients) from a cohort of 279 patients (4.7%) aged 6–73 yr with critical influenza pneumonia. Nine and...

Previous genome-wide association studies (GWASs) of stroke - the second leading cause of death worldwide - were conducted predominantly in populations of European ancestry1,2. Here, in cross-ancestry GWAS meta-analyses of 110,182 patients who have had a stroke (five ancestries, 33% non-European) and 1,503,898 control individuals, we identify associ...

Objective To perform a critical review of studies examining the relation between adverse childhood experiences (ACEs) and substance use (SU) among university students. Methods Observational studies reporting SU of university students for whom ACEs were assessed were identified using PubMed, CINAHL, PsycINFO & ERIC and Web of Science from January 1...

The epidemiological and societal burden of dementia is expected to increase in the coming decades due to the world population aging. In this context, the evaluation of the potential impact of intervention scenarios aiming at reducing the prevalence of dementia risk factors is an active area of research. However, such studies must account for the as...

Covid-19 vaccine hesitancy among young adults is a current public health issue that needs to be addressed considering the seasonally driven waves of disease and the administration of vaccine boosters. As a prevention measure, the EU Covid certificate had been implemented to increase vaccine uptake, but its application was controversial. Our study i...

Purpose: The aim of this study was to (1) investigate the association of parental death and illness with suicidal ideation using a large sample of university students and (2) test whether associations were moderated by perceived family support. Methods: We used data from N = 15,008 French university students enrolled in the i-Share cohort (mean...

Introduction Clonal hematopoiesis of indeterminate potential (CHIP) are defined by the detection of leukemia-associated somatic mutations in leukocytes of healthy subjects. CHIP are associated with increased risk of cardiovascular event (CVE) related to atherothrombosis (myocardial infarction MI, stroke) independently of traditional cardiovascular...

BACKGROUND The use of the Internet to look for information about vaccines has skyrocketed in the last years, especially with the Covid-19 crisis. Digital vaccine literacy refers to understanding, trust, appraisal and application of vaccine-related information online. OBJECTIVE To develop a tool measuring digital vaccine literacy and assess its psy...

Background The use of the internet to look for information about vaccines has skyrocketed in the last years, especially with the COVID-19 pandemic. Digital vaccine literacy (DVL) refers to understanding, trust, appraisal, and application of vaccine-related information online. Objective This study aims to develop a tool measuring DVL and assess its...

Cerebral small vessel disease is a leading cause of stroke and a major contributor to cognitive decline and dementia, but our understanding of specific genes underlying the cause of sporadic cerebral small vessel disease is limited. We report a genome-wide association study and a whole-exome association study on a composite extreme phenotype of cer...

Over the past few decades, neuroimaging has become a ubiquitous tool in basic research and clinical studies of the human brain. However, no reference standards currently exist to quantify individual differences in neuroimaging metrics over time, in contrast to growth charts for anthropometric traits such as height and weight ¹ . Here we assemble an...

Characterization of the genetic landscape of Alzheimer’s disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/‘proxy’ AD cases and 677,663 controls. We found 75 ris...

Background Cannabis use in university students is associated with academic achievement failure and health issues. The objective of the study was to evaluate the association between attention deficit hyperactivity disorder (ADHD) symptoms and cannabis use after 1 year among students according to previous cannabis use. Methods Students in France wer...

Objectives : To report the characteristics of vaccine-hesitant individuals in a French-speaking adult population in the context of the SARS-CoV-2 pandemic; and to identify predictors of hesitancy about Covid-19-related vaccines. Methods : Between April and May 2020, 1640 French-speaking adults participating in an online cohort were classified acco...

Background: Little is known about psychoactive substance use in students, apart from tobacco, alcohol, and cannabis. Objectives: This study investigated the prevalence of substance use and overlap between various psychoactive substances in students. Methods: This cross-sectional study was conducted in 10,066 students included in the i-Share co...

Objectives To describe the use of antihypertensive and lipid-lowering drugs in post-stroke secondary prevention in France. Methods and results A prospective cohort study based on a representative sample of the French health insurance system database. All patients aged 45 and over, hospitalized for a first stroke between 1 January 2009 and 31 Decem...

Objective To assess whether the French “Amis aussi la nuit” (“Friends also at night”) campaign on peer-support concerning binge drinking and cannabis use in a party setting reached young adults aged 17–25 years, and how it was perceived by them. Methods A posttest evaluation of the campaign using a mixed-methods design was performed. Quantitative...

Mental health literacy (MHL) is a determinant of psychological well-being in young people. A random-ized controlled design was used to evaluate the appreciation and effectiveness of an interactive video on French University students' MHL (knowledge about depression and suicidal behavior, mental health help-seeking behaviors, stigma and misconceptio...

Background Cerebrovascular disease (CVD), a major contributor of cognitive aging, is characterized by subclinical damage visualized on brain MRI, including covert brain infarcts, white matter hyperintensities (WMH) and dilated perivascular spaces (dPVS). Few protective factors for brain vascular health, that may help prevent stroke and dementia, ha...

Background Growing epidemiological evidence suggests an adverse relationship between exposure to air pollutants and cognitive decline. However, there is still some heterogeneity in the findings, with inconsistent results depending on the pollutant and cognitive domain considered. We aimed to evaluate if air pollution was associated with global and...

Background Subcortical brain structures play a key role in pathological processes of many age‐related neurodegenerative disorders. Mounting evidence suggests that factors already present at an early age play a crucial role in the development of common late‐life neurological diseases, including genetic factors that can influence both brain maturatio...

Background Stroke and transient ischemic attack confer greater risk of cognitive decline and dementia. Aims We used data from the Perindopril Protection Against Recurrent Stroke Study (PROGRESS), a blood pressure-lowering randomized controlled trial in stroke/transient ischemic attack. We evaluated overall and sex-specific differences in treatment...

Previous studies have shown the negative impact of the COVID-19 epidemic on students’ mental health. It is, however, uncertain whether students are really at higher risk of mental health disturbances than non-students and if they are differentially impacted by lockdown periods over time. The objective of our study was to compare the frequency of de...

Background and Objective Fish intake may prevent cerebrovascular disease (CVD), yet the mechanisms are unclear, especially regarding its impact on subclinical damage. Assuming that fish may have pleiotropic effect on cerebrovascular health, we investigated the association of fish intake with global CVD burden based on brain MRI markers. Methods Th...

Introduction: Although increased cholesterol level has been acknowledged as a risk factor for dementia, evidence synthesis based on published data has yielded mixed results. This is especially relevant in older adults where individual studies report non-linear relationships between cholesterol and cognition and, in some cases, find higher choleste...

Perivascular space burden (PVS) is an emerging and possibly the earliest magnetic resonance imaging (MRI)-marker of cerebral small vessel disease (cSVD), a leading cause of stroke and dementia. Its molecular underpinnings are unknown. Genome-wide and whole-exome association studies in 40,095 participants (21 population-based cohorts, 66.3±8.6 years...

Long-term blood pressure variability (BPV), an increasingly recognized vascular risk factor, is challenging to analyze. The objective was to assess the impact of BPV modeling on its estimated effect on the risk of stroke. We used data from a secondary stroke prevention trial, PROGRESS (Perindopril Protection Against Stroke Study), which included 61...

Functional connectivity analyses of fMRI data have shown that the activity of the brain at rest is spatially organized into resting-state networks (RSNs). RSNs appear as groups of anatomically distant but functionally tightly connected brain regions. Inter-RSN intrinsic connectivity analyses may provide an optimal spatial level of integration to an...

This study aimed to investigate the role of cardiovascular health (CVH) and vascular events as potential contributors to socioeconomic inequalities in dementia using causal mediation analyses. We used data from the Three-City Cohort, a French population-based study with 12 years of follow-up, with active search of dementia cases and validated diagn...

Background Subcortical brain structures play a key role in pathological processes of age-related neurodegenerative disorders. Mounting evidence also suggests that early-life factors may have an impact on the development of common late-life neurological diseases, including genetic factors that can influence both brain maturation and neurodegeneratio...

Research links high blood pressure variability (BPV) with stroke and cerebrovascular disease, however, its association with cognition remains unclear. Moreover, it remains uncertain which BP-derived parameter (ie, variability or mean) holds more significance in understanding vascular contributions to cognitive impairment. We searched PubMed, Embase...

We report on MRi-Share, a multi-modal brain MRI database acquired in a unique sample of 1870 young healthy adults, aged 18–35 years, while undergoing university-level education. MRi-Share contains structural (T1 and FLAIR), diffusion (multispectral), susceptibility-weighted (SWI), and resting-state functional imaging modalities. Here, we described...

The relationship between hippocampal subfield volumetry and verbal list-learning test outcomes have mostly been studied in clinical and elderly populations, and remain controversial. For the first time, we characterized a relationship between verbal list-learning test outcomes and hippocampal subfield volumetry on two large separate datasets of 447...