Kostas Tsilidis

Kostas Tsilidis
University of Ioannina | UOI · Department of Hygiene and Epidemiology

PhD in Epidemiology

About

408
Publications
48,520
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
16,566
Citations

Publications

Publications (408)
Article
Background Waist circumference (WC) and its allometric counterpart, “a body shape index” (ABSI), are risk factors for colorectal cancer (CRC); however, it is uncertain whether associations with these body measurements are limited to specific molecular subtypes of the disease. Methods Data from 2,772 CRC cases and 3,521 controls were pooled from fou...
Article
Background: Current evidence suggests higher physical activity (PA) levels are associated with a reduced risk of colorectal cancer (CRC). However, the mediating role of the circulating metabolome in this relationship remains unclear. Methods: Targeted metabolomics data from 6,055 participants in the EPIC cohort were used to identify metabolites as...
Preprint
Full-text available
Excessive adiposity increases disease risk, yet the exact underlying mechanisms remain unknown. We compared sex-specific metabolic signatures (MSs) of adiposity indices (non-allometric: body fat %, waist circumference, hip circumference, waist-to-hip ratio, body mass index; allometric: a body shape index, hip index, waist-to-hip-index ratio) and ex...
Article
Full-text available
Background Ultra-processed food (UPF) consumption has been linked with higher risk of mortality. This multi-centre study investigated associations between food intake by degree of processing, using the Nova classification, and all-cause and cause-specific mortality. Methods This study analyzed data from the European Prospective Investigation into...
Article
Background Adiposity is an established risk factor for colorectal cancer (CRC). The pathways underlying this relationship, and specifically the role of circulating proteins, are unclear. Methods Utilizing two-sample univariable Mendelian randomization (UVMR), multivariable Mendelian randomization (MVMR), and colocalization, based on summary data f...
Article
Full-text available
Background and Objective: Nutrimetabolomics may reveal novel insights into early metabolic alterations and the role of dietary exposures on prostate cancer (PCa) risk. We aimed to prospectively investigate the associations between plasma metabolite concentrations and PCa risk, including clinically relevant tumor subtypes. Methods: We used a targete...
Article
Full-text available
Background Whether blood lipids are causally associated with colorectal cancer (CRC) risk remains unclear. Methods Using two-sample Mendelian randomisation (MR), our study examined the associations of genetically-predicted blood concentrations of lipids and lipoproteins (primary: LDL-C, HDL-C, triglycerides, and total cholesterol), and genetically...
Preprint
Full-text available
Background: Preclinical, observational, and genetic epidemiological evidence implicate circulating lipids in cancer development. The role of approved and emerging lipid-perturbing medications in cancer risk is unclear. Patients and methods: We employed cis-Mendelian randomization (MR) and colocalisation to evaluate the role of 5 lipid-perturbing dr...
Article
Background The underlying biological mechanisms linking blood pressure (BP) and cardiovascular diseases (CVD) are only partly understood. We aimed to identify metabolic signatures associated with systolic and diastolic BP and investigate their subsequent association with risk of CVD. Methods and Results The study included 201 742 UK Biobank partic...
Article
Full-text available
Background/Objectives: Lifestyle interventions such as dietary changes have been proposed to control the cardiometabolic risk factors and thus prevent cardiovascular (CV) disease (CVD). We performed an umbrella review to investigate whether different dietary patterns affect CV risk in individuals with at least one cardiometabolic risk factor (hyper...
Article
Full-text available
Introduction Polygenic Risk Scores (PRS) are an emerging tool for predicting an individual’s genetic risk to a complex trait. Several methods have been proposed to construct and calculate these scores. Here, we develop a biologically driven PRS using the UK BioBank cohort through validated protein interactions (PPI) and network construction for pso...
Article
Full-text available
We have previously shown that body mass index attenuates a positive association of platelet count (PLT) and inverse of mean platelet volume (MPV) with lung cancer risk in men. It is unclear whether fat mass, lean mass, or liver function tests (LFTs) show similar attenuations. Using bioelectrical impedance measurements (UK Biobank cohort) and multiv...
Preprint
Full-text available
Water quality assessment is essential for understanding and managing water resources and identifying potential health and environmental risks. A method for a parameter valuation should be characterized by high accuracy and precision. This study presents a comprehensive comparative analysis of three crucial water quality parameters (especially in wa...
Article
Full-text available
Background Inflammation and immune dysregulation are hypothesized contributors to endometrial carcinogenesis; however, the precise underlying mechanisms remain unclear. Methods We measured pre-diagnostically 152 plasma protein biomarkers in 624 endometrial cancer case-control pairs nested within the European Prospective Investigation into Cancer a...
Article
Full-text available
Background Adiposity has been characterised as a modifiable risk factor of prostate cancer. Its association with outcomes after prostate cancer diagnosis, however, needs to be better understood and obtain more evidence to assist the development of lifestyle guidance for prostate cancer patients. Methods We investigated the associations between adi...
Article
We investigated the effects of 35 inflammatory cytokines on respiratory outcomes, including COVID-19, asthma (atopic and non-atopic), chronic obstructive pulmonary disease (COPD), and pulmonary function indices, using Mendelian randomization and colocalization analyses. The emerging associations were further explored using observational analyses in...
Article
Background Folate is involved in multiple genetic, epigenetic, and metabolic processes, and inadequate folate intake has been associated with an increased risk of cancer. Objective We examined whether folate intake is differentially associated with colorectal cancer (CRC) risk according to somatic mutations in genes linked to CRC using targeted se...
Article
Background Understanding the role of circulating proteins in prostate cancer risk can reveal key biological pathways and identify novel targets for cancer prevention. Methods We investigated the association of 2002 genetically predicted circulating protein levels with risk of prostate cancer overall, and of aggressive and early onset disease, usin...
Article
Full-text available
Background The effect of Ramadan intermittent fasting (RIF) on the metabolic profile, anthropometry and blood pressure has been investigated in multiple studies. However, it is still unknown to what extent changes in nutrient intakes contribute to these changes. Methods This observational study was conducted in London (UK) in 2019. The study colle...
Article
Full-text available
Background Non-alcoholic fatty liver disease (NAFLD) and metabolic syndrome (MetS) are implicated in the aetiology of non-communicable diseases. Our study aimed to evaluate associations between NAFLD and MetS with overall and cause-specific mortality. Methods We used dietary, lifestyle, anthropometric and metabolic biomarker data from a random sub...
Article
Full-text available
Regular, long-term aspirin use may act synergistically with genetic variants, particularly those in mechanistically relevant pathways, to confer a protective effect on colorectal cancer (CRC) risk. We leveraged pooled data from 52 clinical trial, cohort, and case-control studies that included 30,806 CRC cases and 41,861 controls of European ancestr...
Article
Full-text available
Background Obesity is associated with chronic low-grade inflammation, which is linked to cancer development. Abdominal obesity (a body mass index, ABSI), however, has unusually been associated inversely with cutaneous malignant melanoma (CMM), while general obesity (body mass index, BMI) is associated positively. Leucocytes participate in inflammat...
Article
Full-text available
The role of diet in colorectal cancer prognosis is not well understood and specific lifestyle recommendations are lacking. We searched for randomised controlled trials (RCTs) and longitudinal observational studies on post‐diagnosis dietary factors, supplement use and colorectal cancer survival outcomes in PubMed and Embase from inception until 28th...
Article
Full-text available
Based on the World Cancer Research Fund Global Cancer Update Programme, we performed systematic reviews and meta‐analyses to investigate the association of post‐diagnosis adiposity, physical activity, sedentary behaviour, and dietary factors with colorectal cancer prognosis. We searched PubMed and Embase until 28th February, 2022. An independent ex...
Article
Full-text available
The adiposity influence on colorectal cancer prognosis remains poorly characterised. We performed a systematic review and meta‐analysis on post‐diagnosis adiposity measures (body mass index [BMI], waist circumference, waist‐to‐hip ratio, weight) or their changes and colorectal cancer outcomes. PubMed and Embase were searched through 28 February 202...
Article
Full-text available
Low physical activity and high sedentary behaviour have been clearly linked with colorectal cancer development, yet data on their potential role in colorectal cancer survival is limited. Better characterisation of these relationships is needed for the development of post‐diagnosis physical activity and sedentary behaviour guidance for colorectal ca...
Article
Background Colorectal cancer (CRC) is the third-most-common cancer worldwide and its rates are increasing. Elevated body mass index (BMI) is an established risk factor for CRC, although the molecular mechanisms behind this association remain unclear. Using the Mendelian randomization (MR) framework, we aimed to investigate the mediating effects of...
Article
Full-text available
Background Menopausal hormone therapy (MHT), a common treatment to relieve symptoms of menopause, is associated with a lower risk of colorectal cancer (CRC). To inform CRC risk prediction and MHT risk-benefit assessment, we aimed to evaluate the joint association of a polygenic risk score (PRS) for CRC and MHT on CRC risk. Methods We used data fro...
Article
Background: Understanding the role of circulating proteins in prostate cancer risk can reveal key biological pathways and identify novel targets for cancer prevention. Methods: We investigated the association of 2,002 genetically predicted circulating protein levels with risk of prostate cancer overall, and of aggressive and early onset disease, us...
Article
Background The link between the pre‐diagnostic use of statins and testosterone replacement therapy and their impact on hormone‐related cancers, prostate cancer, colorectal cancer, and male breast cancer survival remains a topic of controversy. Further, there is a knowledge gap concerning the joint effects of statins and testosterone replacement the...
Preprint
Full-text available
Adiposity is an established risk factor for colorectal cancer (CRC). However, the pathways underlying this relationship, and specifically the role of the circulating proteome, is unclear. Utilizing two-sample Mendelian randomization and colocalization, based on summary data from large sex-combined and sex-specific genetic studies, we estimated the...
Article
Full-text available
Background Obesity has been positively associated with most molecular subtypes of colorectal cancer (CRC); however, the magnitude and the causality of these associations is uncertain. Methods We used Mendelian randomization (MR) to examine potential causal relationships between body size traits (body mass index [BMI], waist circumference, and body...
Article
Full-text available
High cortisol production in Cushing’s syndrome leads to fat centralisation. The influence of modest cortisol variations on body shape, however, is less clear. We examined potentially causal associations between morning plasma cortisol and body shape and obesity with inverse-variance weighted random-effects models in a two-sample Mendelian randomisa...
Article
Background The dramatic change in lifestyle associated with Ramadan fasting raises questions about its effect on metabolism and health. Metabolites, as the end product of metabolism, are excellent candidates to be studied in this regard. Objective This study aims to investigate the effect of Ramadan fasting on the metabolic profile and risk of chr...
Article
Full-text available
Background Traditional body-shape indices such as Waist Circumference (WC), Hip Circumference (HC), and Waist-to-Hip Ratio (WHR) are associated with colorectal cancer (CRC) risk, but are correlated with Body Mass Index (BMI), and adjustment for BMI introduces a strong correlation with height. Thus, new allometric indices have been developed, namely...
Article
Full-text available
Background Tumour-promoting inflammation is a “hallmark” of cancer and conventional epidemiological studies have reported links between various inflammatory markers and cancer risk. The causal nature of these relationships and, thus, the suitability of these markers as intervention targets for cancer prevention is unclear. Methods We meta-analysed...
Article
Full-text available
Background Obesity and diabetes are associated inversely with low‐grade prostate cancer risk and affect steroid hormone synthesis but whether they modify each other's impact on prostate cancer risk remains unknown. Methods We examined the independent associations of diabetes, body mass index (BMI), ‘a body shape index’ (ABSI), hip index (HI), circ...
Article
Full-text available
Background Sedentary behaviours have been associated with increased risks of some common cancers in epidemiological studies; however, it is unclear if these associations are causal. Methods We used univariable and multivariable two‐sample Mendelian randomisation (MR) to examine potential causal relationships between sedentary behaviours and risks...
Article
Background High red meat and/or processed meat consumption are established colorectal cancer risk factors. We conducted a genome-wide gene–environment (GxE) interaction analysis to identify genetic variants that may modify these associations. Methods A pooled sample of 29,842 colorectal cancer cases and 39,635 controls of European ancestry from 27...
Article
Full-text available
Background: Co-existing long-term conditions (LTC) in psoriasis and their potential causal associations with the disease are not well-established. Objectives: This study aims to determine distinct clusters of LTC in people with psoriasis and the potential bi-directional causal association between these LTC and psoriasis. Methods: Using latent...
Article
Full-text available
Background Platelet count (PLT) is associated positively with lung cancer risk but has a more complex association with body mass index (BMI), positive only in women (mainly never smokers) and inverse in men (mainly ever smokers), raising the question whether platelets interact with obesity in relation to lung cancer risk. Prospective associations o...
Article
BACKGROUND Mendelian randomization (MR) offers a powerful approach to study potential causal associations between exposures and health outcomes by using genetic variants associated with an exposure as instrumental variables. In this systematic review, we aimed to summarize previous MR studies and to evaluate the evidence for causality for a broad r...
Preprint
Full-text available
Background Understanding the role of circulating proteins in prostate cancer risk can reveal key biological pathways and identify novel targets for cancer prevention. Methods We investigated the association of 2,002 genetically predicted circulating protein levels with risk of prostate cancer overall, and of aggressive and early onset disease, usin...
Article
Full-text available
Abstract Background Obesity is associated with type 2 diabetes mellitus and chronic low-grade inflammation. Although chronic inflammatory conditions and diabetes are associated with anaemia, less is known about associations of obesity and body shape, independent of each other, with erythrocyte and reticulocyte parameters. Methods We investigated th...
Article
Full-text available
Background: Epidemiological and experimental evidence suggests that higher folate intake is associated with a decreased colorectal cancer (CRC) risk; however, the mechanisms underlying this relationship are not fully understood. Genetic variation that may have a direct or indirect impact on folate metabolism can provide insights into folate's role...
Article
Full-text available
Background Persistent infection by oncogenic human papillomavirus (HPV) is necessary although not sufficient for development of cervical cancer. Behavioural, environmental, or comorbid exposures may promote or protect against malignant transformation. Randomised evidence is limited and the validity of observational studies describing these associat...
Preprint
Full-text available
Infections can lead to persistent or long-term symptoms and diseases such as shingles after varicella zoster, cancers after human papillomavirus, or rheumatic fever after streptococcal infections(1,2). Similarly, infection by SARS-CoV-2 can result in Long COVID, a condition characterized by symptoms of fatigue and pulmonary and cognitive dysfunctio...
Article
Full-text available
Objective To explore the associations between adiposity indices, assessed at or after a diagnosis of prostate cancer, and mortality. Design Systematic review and meta-analysis. Data sources PubMed and Embase, from inception to 16 November 2022. Eligibility criteria for selecting studies Cohort studies or randomised controlled trials of men with...
Article
Full-text available
BACKGROUND: Diabetes is an established risk factor for colorectal cancer. However, the mechanisms underlying this relationship still require investigation and it is not known if the association is modified by genetic variants. To address these questions, we undertook a genome-wide gene-environment interaction analysis. METHODS: We used data from 3...
Article
Full-text available
Background The Mediterranean diet has been associated with lower risk of breast cancer (BC) but evidence from prospective studies on the role of Mediterranean diet on BC survival remains sparse and conflicting. We aimed to investigate whether adherence to Mediterranean diet prior to diagnosis is associated with overall and BC-specific mortality. M...
Article
Full-text available
Background Associations of body shape with breast cancer risk, independent of body size, are unclear because waist and hip circumferences are correlated strongly positively with body mass index (BMI). Methods We evaluated body shape with the allometric “a body shape index” (ABSI) and hip index (HI), which compare waist and hip circumferences, corr...
Article
Full-text available
Colorectal cancer risk can be impacted by genetic, environmental, and lifestyle factors, including diet and obesity. Gene-environment interactions (G × E) can provide biological insights into the effects of obesity on colorectal cancer risk. Here, we assessed potential genome-wide G × E interactions between body mass index (BMI) and common SNPs for...
Article
Full-text available
Aims/hypothesis: Epidemiological studies have generated conflicting findings on the relationship between glucose-lowering medication use and cancer risk. Naturally occurring variation in genes encoding glucose-lowering drug targets can be used to investigate the effect of their pharmacological perturbation on cancer risk. Methods: We developed g...
Article
Full-text available
Background: Metabolic syndrome is considered an important risk factor for cognitive decline and dementia. However, the evidence in middle-aged individuals is still conflicting. The aim of the study was to explore the association between metabolic syndrome and its individual components with cognitive function and to investigate possible interaction...
Preprint
Full-text available
Background: Tumour-promoting inflammation is a ″hallmark″ of cancer and conventional epidemiological studies have reported links between various inflammatory markers and cancer risk. The causal nature of these relationships and, thus, the suitability of these markers as intervention targets for cancer prevention is unclear. Methods: We meta-analyse...
Poster
Full-text available
Risk factors and molecular subtypes of colorectal cancer: a systematic review and meta-analysis.
Article
Full-text available
Background: The causal relevance of polyunsaturated fatty acids (PUFAs) for risk of site-specific cancers remains uncertain. Methods: Using a Mendelian randomization (MR) framework, we assessed the causal relevance of PUFAs for risk of cancer in European and East Asian ancestry individuals. We defined the primary exposure as PUFA desaturase activit...
Article
Full-text available
Background Mendelian randomization (MR) studies are susceptible to metadata errors (e.g. incorrect specification of the effect allele column) and other analytical issues that can introduce substantial bias into analyses. We developed a quality control (QC) pipeline for the Fatty Acids in Cancer Mendelian Randomization Collaboration (FAMRC) that can...
Article
Full-text available
Evidence linking body fatness to breast cancer (BC) prognosis is limited. While it seems that excess adiposity is associated with poorer BC survival, there is uncertainty over whether weight changes reduce mortality. This study aimed to assess the association between body fatness and weight changes pre-and postdiagnosis and overall mortality and BC...
Article
Full-text available
Congenital cryptorchidism is a well-established risk factor of testicular malignancies. However, there is still remarkable variability in the measures of associations between of these two clinical entities. The current meta-analysis investigates the up-to-date risk of testicular cancer in adults with a history of surgically corrected congenital cry...
Article
Full-text available
Background Food processing has been hypothesised to play a role in cancer development; however, data from large-scale epidemiological studies are scarce. This study investigated the association between dietary intake according to amount of food processing and risk of cancer at 25 anatomical sites using data from the European Prospective Investigati...
Preprint
Introduction Sedentary behaviours have been associated with increased risks of some common cancers in epidemiological studies; however, it is unclear if these associations are causal. Methods We used univariable and multivariable two-sample Mendelian randomization (MR) to examine potential causal relationships between sedentary behaviours and risk...
Article
Full-text available
Background Amino acid metabolism is dysregulated in colorectal cancer patients; however, it is not clear whether pre-diagnostic levels of amino acids are associated with subsequent risk of colorectal cancer. We investigated circulating levels of amino acids in relation to colorectal cancer risk in the European Prospective Investigation into Cancer...