Marios Georgakis

Ludwig-Maximilians-University of Munich & Massachusetts General Hospital · Institute for Stroke and Dementia Research (ISD) & Center for Genomic Medicine (CGM)

Background: The CCL2/CCR2 axis governs monocyte trafficking and recruitment to atherosclerotic lesions. Human genetic analyses and population-based studies support an association between circulating CCL2 levels and atherosclerosis. Still, it remains unknown whether pharmacological targeting of CCR2, the main CCL2 receptor, would provide protection...

Background and Objectives Clopidogrel is an antiplatelet used in both primary and secondary prevention of cardiovascular diseases. It is a prodrug, requiring CYP2C19 for its metabolism to the active metabolite. The ABCD-GENE score, combining clinical attributes (age, body mass index, chronic kidney disease, diabetes mellitus), with genetic informat...

Background: Valproate is a candidate for ischemic stroke prevention due to its anti-atherosclerotic effects in vivo. Although valproate use is associated with decreased ischemic stroke risk in observational studies, confounding by indication precludes causal conclusions. Aims: We applied Mendelian randomization to determine whether genetic varia...

Aim: Interleukin 6 (IL-6) is considered to play a role in the dysbiotic host response in the development of periodontitis. While the inhibition of the IL-6 receptor using monoclonal antibodies is a well-established therapy for some diseases, so far, its potential benefit in patients with periodontitis has not been examined. We tested the associati...

Background: It is increasingly clear that genetic and non-genetic factors account for the association of family history with disease risk in offspring. We sought to distinguish the genetic and non-genetic contributions of family history of stroke and heart disease on incident events by examining adopted and non-adopted individuals. Methods: We exam...

Background and purpose: We performed a two-sample Mendelian randomization (MR) analysis to evaluate the causal effect of genetically proxied AMP-activated protein kinase (AMPK) activation, which is the target of metformin, on functional outcome following ischemic stroke onset. Methods: A total of 44 AMPK-related variants associated with HbA1c (%...

Objective: Genome-wide association studies have identified 1q22 as a susceptibility locus for cerebral small vessel diseases (CSVDs), including non-lobar intracerebral hemorrhage (ICH) and lacunar stroke. In the present study we performed targeted high-depth sequencing of 1q22 in ICH cases and controls to further characterize this locus and priorit...

Objectives: We employed Mendelian randomization to determine whether genetically predicted circulating levels of endothelial-derived adhesion molecules (soluble intercellular adhesion molecule-1 [sICAM-1]), soluble vascular-leukocyte adhesion molecule-1 [sVCAM-1], and soluble-endothelial-leukocyte adhesion molecule [sE-selectin]) were associated w...

Background: Genetic and experimental studies support a causal involvement of interleukin-6 (IL-6) signaling in atheroprogression. While trials targeting IL-6 signaling are underway, any benefits must be balanced against an impaired host immune response. Dissecting the mechanisms that mediate the effects of IL-6 signaling on atherosclerosis could of...

Background: Recent evidence suggests that higher CRP (C-reactive protein) levels are associated with lower risk of Alzheimer disease, speculating that CRP might be involved in Aβ clearance mechanisms. Testing this hypothesis, we explored whether genetically proxied CRP levels are also associated with lobar intracerebral hemorrhage (ICH), commonly...

Introduction: We constructed a polygenic risk score (PRS) for β-amyloid (PRSAβ42) to proxy AD pathology and investigated its association with incident Alzheimer's disease (AD)/amnestic mild cognitive impairment (aMCI) and the influence of cognitive reserve (CR), proxied by educational years, on the relationship between PRSAβ42 and AD/aMCI risk. M...

Background and Objectives: Valproate is a candidate for ischemic stroke prevention due to its anti-atherosclerotic effects in vivo. Although valproate use is associated with decreased ischemic stroke risk in observational studies, confounding by indication precludes causal conclusions. To overcome this limitation, we applied Mendelian randomization...

Background: Intracerebral hemorrhage (ICH) has an estimated heritability of 29%. We developed a genomic risk score for ICH and determined its predictive power in comparison to standard clinical risk factors. Methods: We combined genome-wide association data from individuals of European ancestry for ICH and related traits in a meta-genomic risk s...

Background: Undetermined stroke etiology hampers optimal secondary prevention in a large proportion of young patients. We explored whether genetic screening for clonal hematopoiesis of indetermined potential (CHIP), a novel risk factor for stroke, could identify patients with myeloid precursor lesions or covert myeloid neoplasm requiring specific...

Background: Intracerebral hemorrhage (ICH) is the most devastating adverse outcome for patients on anticoagulants. Clinical risk scores that quantify bleeding risk can guide decision-making in situations when indication or duration for anticoagulation is uncertain. We investigated whether integration of a genetic risk score into an existing risk f...

The risk of early recurrent events after stroke remains high despite currently established secondary prevention strategies. Risk is particularly high in patients with atherosclerosis, with more than 10% of patients experiencing early recurrent events. However, despite the enormous medical burden of this clinical phenomenon, the underlying mechanism...

Introduction: Previous studies have suggested that increased body fat is associated with stroke risk. Advances in imaging-based fat distribution measurements have uncovered distinct biological underpinnings of local fat depots. Here, we explored associations between biologically relevant local adiposity profiles and stroke risk, aiming to refine th...

The risk of early recurrent events after stroke remains high despite currently established secondary prevention strategies. Risk is particularly high in patients with atherosclerosis, with more than 10% of patients experiencing early recurrent events. However, despite the enormous medical burden of this clinical phenomenon, the underlying mechanism...

Background: Pressure wave reflections (PWRs) within the circulation are assessed at various arterial sites by various noninvasive methods. We aimed at reviewing the conflicting data regarding the hypothesis that higher PWRs are associated with higher left ventricular mass and tested whether this association stands for all available indices of PWRs...

Interleukin 6 (IL-6) is considered to play a role in the dysbiotic host response in the development of periodontitis. To explore whether downregulation of IL-6 signaling could represent a viable treatment target for periodontitis, we tested the association of genetically proxied downregulation of IL-6 signaling with periodontitis. As proxies for IL...

Background: Intracerebral hemorrhage (ICH) is the most devastating adverse outcome for patients on anticoagulants. Clinical risk scores (CRS) that quantify bleeding risk can guide decision making in situations when indication or duration for anticoagulation is uncertain. We investigated whether integration of a genetic risk score (GRS) into an exis...

Background and Objectives: Chronic kidney disease (CKD) increases the risk of stroke, but the extent through which this association is mediated by hypertension is unknown. We leveraged large-scale genetic data to explore causal relationships between CKD, hypertension and cerebrovascular disease phenotypes. Methods: We used data from genome-wide ass...

Background and aims Post hoc analyses of clinical trials show that PCSK9 inhibitors might lower lipoprotein(a), but whether this effect contributes to reductions in cardiovascular risk remains unknown. We aimed to assess whether genetically proxied PCSK9 inhibition influences lipoprotein(a) (Lp(a)), and whether any such effect could mediate its eff...

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...

Importance Cerebral small vessel disease (SVD) causes a quarter of strokes and is the most common pathology underlying vascular cognitive impairment and dementia. An important step to developing new treatments is better trial methodology. Disease mechanisms in SVD differ from other stroke etiologies; therefore, treatments need to be evaluated in co...

Background Interleukin 6 (IL-6) signaling is being investigated as a therapeutic target for atherosclerotic cardiovascular disease (CVD). While changes in circulating high-sensitivity C-reactive protein (hsCRP) are used as a marker of IL-6 signaling, it is not known whether there is effect heterogeneity in relation to baseline hsCRP levels or other...

BACKGROUND Imaging features derived from T1-weighted (T1w) images texture analysis were shown to be potential markers of poststroke cognitive impairment, with better sensitivity than atrophy measurement. However, in magnetic resonance images, the signal distribution is subject to variations and can limit transferability of the method between center...

Introduction: It remains unknown whether the global small vessel disease (SVD) burden predicts post-stroke outcomes. Methods: In a prospective multicenter study of 666 ischemic and hemorrhagic stroke patients, we quantified magnetic resonance imaging (MRI)-based SVD markers (lacunes, white matter hyperintensities, microbleeds, perivascular space...

Statins lower low-density lipoprotein (LDL) cholesterol and are widely used for the prevention of atherosclerotic cardiovascular disease. Whether statin-induced LDL reduction increases risk of intracerebral hemorrhage (ICH) has been debated for almost two decades. Here, we explored whether genetically predicted on-statin LDL response is associated...

Background Intracerebral hemorrhage (ICH), the most fatal form of stroke, has an estimated heritability of 29%. Applying a meta-scoring approach, we developed a genomic risk score for ICH and determined its predictive power in comparison to standard clinical risk factors. Methods Using a meta-analytic approach, we combined genome-wide association...

Background and Purpose Vascular risk factors may influence cognitive function and thus represent possible targets for preventive approaches against dementia. Yet it remains unknown, if they associate with cognition independently of the individual genetic risk for dementia. Methods In a population-based study of 1,172 community-dwelling individuals...

Background and aims: Increased risk of stroke, particularly large artery stroke (LAS), has been observed in patients with COVID-19. The biological processes underlying the observed higher risk are still unknown. We explored the association between stroke subtypes and COVID-19 susceptibility to understand whether biological mechanisms specific to SA...

Background The CCL2 (CC-chemokine ligand 2)/CCR2 (CC-chemokine receptor 2) axis governs monocyte recruitment to atherosclerotic lesions. Genetic and epidemiological studies show strong associations of CCL2 levels with atherosclerotic disease. Still, experimental studies testing pharmacological inhibition of CCL2 or CCR2 in atheroprone mice apply wi...

Statins lower low-density lipoprotein (LDL) cholesterol and are widely used for the prevention of atherosclerotic cardiovascular disease. Whether statin-induced LDL reduction increases risk of intracerebral hemorrhage (ICH) has been debated for almost two decades. Here, we explored whether genetically predicted LDL response to statins is associated...

Decades of research have established atherosclerosis as an inflammatory disease. Only recently though, clinical trials provided proof-of-concept evidence for the efficacy of anti-inflammatory strategies with respect to cardiovascular events, thus offering a new paradigm for lowering residual vascular risk. Efforts to target the inflammasome-interle...

Objective: Ischemic stroke etiology remains undetermined in 30% of cases. We explored the genetic architecture of stroke classified as undetermined to test if mechanisms and risk factors underlying large-artery atherosclerotic (LAAS), cardioembolic (CES), and small-vessel stroke (SVS) contribute to its pathogenesis. Methods: We analyzed genome-w...

Introduction: Stroke etiology remains unknown in 30% of cases, hindering secondary prevention efforts. We leveraged human genetic data in order to identify evidence of overlap between stroke of undetermined source and defined stroke etiologies as well as causal relationships with modifiable risk factors. Methods: We analyzed genome-wide data from 1...

Background: Evidence suggests marginal superiority of static aortic systolic blood pressure (aSBP) compared with brachial SBP regarding the association with organ damage and prognosis of cardiovascular disease. The noninvasive 24-hour aSBP assessment is feasible and associates better with presence of left ventricular hypertrophy compared with 24-h...

Background: Frailty is a complex geriatric syndrome arising from a combination of genetic and environmental factors and is associated with adverse health outcomes and mortality. A recent study reported an association between variants of the 9p21-23 locus, associated with a number of age-related disorders, including Alzheimer's disease (AD), and fr...

Background and Objectives Human genetic studies support a key role of interleukin-6 (IL-6) in the pathogenesis of ischemic stroke. Still, there are only limited data from observational studies exploring circulating IL-6 levels as a risk factor for ischemic stroke. Here, we set out to perform a systematic review and meta-analysis of aggregate data o...

Background Although trials suggest that anti‐inflammatory approaches targeting interleukin (IL)‐6 signaling can reduce cardiovascular risk, it remains unknown whether targeting IL‐6 signaling could reduce risk additively to low‐density lipoprotein cholesterol (LDL‐C) lowering. Here, we assess interactions in associations of genetic downregulation o...

Background and purpose: Observational studies suggest an association of stroke with cardiac traits beyond atrial fibrillation, the leading source of cardioembolism. However, controversy remains regarding a causal role of these traits in stroke pathogenesis. Here, we leveraged genetic data to systematically assess associations between cardiac trait...

Previous genome-wide association studies (GWAS) of stroke, the second leading cause of death, have been conducted in populations of predominantly European ancestry.1,2 We undertook cross-ancestry GWAS meta-analyses of stroke and its subtypes in 110,182 stroke patients (33% non-European) and 1,503,898 control individuals of five ancestries from popu...

Background: Higher segregation of functional networks in the brain has been associated with better cognitive abilities in aging (Chan, PNAS, 2014) and higher cognitive resilience against Alzheimer's disease (Ewers, Brain, in press). Here, we elucidated for the first time the genetic and environmental (i.e. cardiovascular) determinants of system se...

Objective- Cardiovascular risk factors have been implicated in the etiology of Cerebral Small Vessel Disease (CSVD), however whether the associations are causal remains unclear in part due to the susceptibility of observational studies to reverse causation and confounding. Here we use Mendelian randomization (MR) to determine which cardiovascular r...

The kidney and the brain, as high-flow end organs relying on autoregulatory mechanisms, have unique anatomic and physiological hemodynamic properties. Similarly, the two organs share a common pattern of microvascular dysfunction as a result of aging and exposure to vascular risk factors (e.g., hypertension, diabetes and smoking) and therefore progr...

White matter hyperintensities (WMH) are among the most common radiological abnormalities in the ageing population and an established risk factor for stroke and dementia. While common variant association studies have revealed multiple genetic loci with an influence on their volume, the contribution of rare variants to the WMH burden in the general p...

Elucidating the causes of stroke is key to developing effective preventive strategies. The Mendelian randomization approach leverages genetic variants related to an exposure of interest to investigate the effects of varying that exposure on disease risk. The random allocation of genetic variants at conception reduces confounding from environmental...

The functional architecture of the brain is composed of distinct networks, where higher system segregation, i.e. greater differentiation of such functional networks, is associated with better cognitive performance. Aging and many neurological diseases have been associated with reduced system segregation and thus cognitive impairment. The genetic ba...

Experimental studies suggest that sodium induced inflammation might be another missing link leading to atherosclerosis. To test the hypothesis that high daily sodium intake induces systemic inflammatory response in humans, we performed a systematic review according to PRISMA guidelines of randomized controlled trials (RCTs) that examined the effect...

Emerging evidence from randomized controlled clinical trials (RCTs) suggests that colchicine has cardiovascular benefits for patients with coronary disease, including benefits for stroke prevention. We performed an updated systematic review and meta-analysis of all RCTs reporting on stroke outcomes during the follow-up of patients with a history of...

Purpose of review: To evaluate whether CSF and circulating neurofilament light chain (NFL), a marker of axonal damage, could discriminate Parkinson’s disease (PD) from atypical parkinsonian syndromes (APS). Recent findings: MEDLINE and SCOPUS were systematically searched, and fifteen studies were included (1035 PD patients,930 APS patients). CSF a...

Background/aim: An alarming increase in vitamin D deficiency even in sunny regions highlights the need for a better understanding of the genetic background of the vitamin D endocrine system and the molecular mechanisms of gene polymorphisms of the vitamin D receptor (VDR). In this study, the serum levels of 25(OH)D3 were correlated with common VDR...

Abstract The aim of this study was to explore the association between genetically predicted circulating levels of immunity and inflammation, and the risk of Alzheimer’s disease (AD) and hippocampal volume, by conducting a two-sample Mendelian Randomization Study. We identified 12 markers of immune cells and derived ratios (platelet count, eosinophi...

Rationale The CC-chemokine ligand-2 (CCL2)/ CC-chemokine receptor-2 (CCR2) axis governs monocyte recruitment to atherosclerotic lesions. Coherent evidence from experimental studies employing genetic deletion of CCL2 or CCR2 and human epidemiological studies support a causal involvement of the CCL2/CCR2 axis in atherosclerosis. Still, preclinical st...

Objective To determine whether MCP-1 (monocyte chemoattractant protein 1) levels in human atherosclerotic plaques associate with plaque vulnerability features. Approach and Results We measured MCP-1 levels in human atherosclerotic plaque samples from 1199 patients in the Athero-EXPRESS Biobank who underwent endarterectomy for treatment of carotid...

Observational studies exploring whether there is a nonlinear effect of blood pressure on cardiovascular disease (CVD) risk are hindered by confounding. This limitation can be overcome by leveraging randomly allocated genetic variants in nonlinear Mendelian randomization analyses. Based on their association with blood pressure traits in a genome-wid...

White matter hyperintensities (WMH) are among the most common radiological abnormalities in the ageing population and an established risk factor for stroke and dementia. While common variant association studies have revealed multiple genetic loci with an influence on WMH volume, the contribution of rare variants to WMH burden in the general populat...

Objective: To determine the association between circulating interleukin-6 (IL-6) levels and risk of incident ischemic stroke in the general population. Methods: Following the PRISMA guidelines, we systematically searched the literature for population-based prospective cohort studies exploring the association between circulating IL-6 levels and risk...

Introduction: Midlife clustering of vascular risk factors has been associated with late-life dementia, but causal effects of individual biological and lifestyle factors remain largely unknown. Methods: Among 229,976 individuals (mean follow-up 9 years), we explored whether midlife cardiovascular health measured by Life's Simple 7 (LS7) is associ...

In Reply We thank Eroğlu and Eroğlu for their interest in our article¹ and for discussing endothelial calcium influx as a potential mechanism underlying the observed association between serum monocyte-chemoattractant protein–1 (MCP-1) levels and cardiovascular mortality. While this is an interesting hypothesis, we feel there are limited data to sup...

Aims: We performed a Mendelian randomization (MR) study to elucidate the associations of ever smoking, lifelong smoking duration, and smoking cessation with heart failure (HF) risk. Methods and results: We extracted genetic variants associated with smoking initiation, age at initiation of regular smoking, cigarettes per day, and smoking cessatio...

Background: Monocyte chemoattractant protein-1 (MCP-1) is a chemokine recruiting monocytes to the atherosclerotic plaque. Experimental, genetic, and epidemiological data support a key role of MCP-1 in atherosclerosis. Yet, the translational potential of targeting MCP-1 signaling for lowering vascular risk is limited by the lack of data on plaque MC...

Drugs whose targets have genetic evidence to support efficacy and safety are more likely to be approved after clinical development. In this paper, we provide an overview of how natural sequence variation in the genes that encode drug targets can be used in Mendelian randomization analyses to offer insight into mechanism-based efficacy and adverse e...

Drugs whose targets have genetic evidence to support efficacy and safety are more likely to be approved after clinical development. In this paper, we provide an overview of how natural sequence variation in the genes that encode drug targets can be used in Mendelian randomization analyses to offer insight into mechanism-based efficacy and adverse e...

Background and Purpose Assessing whether modifiable risk factors are causally associated with stroke risk is important in planning public health measures, but determining causality can be difficult in epidemiological data. We evaluated whether modifiable lifestyle factors including educational attainment, smoking, and body mass index are causal ris...

Drugs whose targets have genetic evidence to support efficacy and safety are more likely to be approved after clinical development. In this paper, we provide an overview of how natural sequence variation in the genes that encode drug targets can be used in Mendelian randomization analyses to offer insight into mechanism-based efficacy and adverse e...

Aims/hypothesis Our aim was to investigate the relationship between average blood glucose levels and incident CHD in individuals without diabetes mellitus. Methods To investigate average blood glucose levels, we studied HbA 1c as predicted by 40 variants previously shown to be associated with both type 2 diabetes and HbA 1c . Linear and non-linear...

Objective We employed Mendelian randomization (MR) to explore the effects of genetic predisposition to type 2 diabetes (T2D), hyperglycemia, insulin resistance, and β-cell dysfunction on risk of stroke subtypes and related cerebrovascular phenotypes. Methods We selected instruments for genetic predisposition to T2D (74,124 cases, 824,006 controls)...