Introduction: The coronavirus disease 2019 (COVID-19) pandemic has led to the death of almost 7 million people, however, with a cumulative incidence of 0.76 billion, most people survive COVID-19.... Show moreIntroduction: The coronavirus disease 2019 (COVID-19) pandemic has led to the death of almost 7 million people, however, with a cumulative incidence of 0.76 billion, most people survive COVID-19. Several studies indicate that the acute phase of COVID-19 may be followed by persistent symptoms including fatigue, dyspnea, headache, musculoskeletal symptoms, and pulmonary functional-and radiological abnormalities. However, the impact of COVID-19 on long-term health outcomes remains to be elucidated. Aims: The Precision Medicine for more Oxygen (P4O2) consortium COVID-19 extension aims to identify long COVID patients that are at risk for developing chronic lung disease and furthermore, to identify treatable traits and innovative personalized therapeutic strategies for prevention and treatment. This study aims to describe the study design and first results of the P4O2 COVID-19 cohort. Methods: The P4O2 COVID-19 study is a prospective multicenter cohort study that includes nested personalized counseling intervention trial. Patients, aged 40-65 years, were recruited from outpatient post-COVID clinics from five hospitals in The Netherlands. During study visits at 3-6 and 12-18 months post-COVID-19, data from medical records, pulmonary function tests, chest computed tomography scans and biological samples were collected and questionnaires were administered. Furthermore, exposome data was collected at the patient's home and state-of-the-art imaging techniques as well as multi-omics analyses will be performed on collected data. Results: 95 long COVID patients were enrolled between May 2021 and September 2022. The current study showed persistence of clinical symptoms and signs of pulmonary function test/radiological abnormalities in post-COVID patients at 3-6 months post-COVID. The most commonly reported symptoms included respiratory symptoms (78.9%), neurological symptoms (68.4%) and fatigue (67.4%). Female sex and infection with the Delta, compared with the Beta, SARS-CoV-2 variant were significantly associated with more persisting symptom categories. Conclusions: The P4O2 COVID-19 study contributes to our understanding of the long-term health impacts of COVID-19. Furthermore, P4O2 COVID-19 can lead to the identification of different phenotypes of long COVID patients, for example those that are at risk for developing chronic lung disease. Understanding the mechanisms behind the different phenotypes and identifying these patients at an early stage can help to develop and optimize prevention and treatment strategies. Show less
The aim of this thesis was to study the cardiometabolic consequences of obesity and weight gain during the life course. We investigated the association between body mass index (BMI) and... Show moreThe aim of this thesis was to study the cardiometabolic consequences of obesity and weight gain during the life course. We investigated the association between body mass index (BMI) and cardiometabolic disease using Mendelian randomization. We observed that all BMI-associated gene sets, grouped based on tissue expression, were similarly associated with increased risks of cardiometabolic disease. We observed that abdominal adiposity in adolescence was associated with early changes in metabolomic measures indicative of an atherogenic profile already present in young men. Weight gain during adulthood was specifically related to an atherogenic metabolic profile, in addition to increased adipocyte size. Adult weight gain between age 20 years and middle age was associated with increased visceral and liver fat at middle age. Additionally, the association between adult weight gain and insulin resistance at middle age was partly mediated by increased levels of visceral and liver fat at middle age. Lastly, we observed that a favourable body fat distribution as well as metabolic profile are associated with a decreased risk of incident cardiometabolic disease in a population with obesity. Overall, the results of this thesis emphasize the importance of maintaining a stable body weight during young adulthood throughout middle age. Show less
Verkouter, I.; Noordam, R.; Loh, N.Y.; Dijk, K.W. van; Zock, P.L.; Mook-Kanamori, D.O.; ... ; Mutsert, R. de 2021
Context: Weight gain during adulthood increases cardiometabolic disease risk, possibly through adipocyte hypertrophy.Objective: We aimed to study the specific metabolomic profile of adult weight... Show moreContext: Weight gain during adulthood increases cardiometabolic disease risk, possibly through adipocyte hypertrophy.Objective: We aimed to study the specific metabolomic profile of adult weight gain, and to examine its association with adipocyte volume.Methods: Nuclear magnetic resonance-based metabolomics were measured in the Netherlands Epidemiology of Obesity (NEO) study (n=6347, discovery) and Oxford Biobank (n=6317, replication). Adult weight gain was calculated as the absolute difference between body mass index (BMI) at middle age and recalled BMI at age 20 years. We performed linear regression analyses with both exposures BMI at age 20 years and weight gain, and separately with BMI at middle age in relation to 149 serum metabolomic measures, adjusted for age, sex, and multiple testing. Additionally, subcutaneous abdominal adipocyte biopsies were collected in a subset of the Oxford Biobank (n=114) to estimate adipocyte volume.Results: Mean (SD) weight gain was 4.5 (3.7) kg/m(2) in the NEO study and 3.6 (3.7) kg/m(2) in the Oxford Biobank. Weight gain, and not BMI at age 20 nor middle age, was associated with concentrations of 7 metabolomic measures after successful replication, which included polyunsaturated fatty acids, small to medium low-density lipoproteins, and total intermediate-density lipoprotein. One SD weight gain was associated with 386 mu m(3) (95% CI, 143-629) higher median adipocyte volume. Adipocyte volume was associated with lipoprotein particles specific for adult weight gain.Conclusion: Adult weight gain is associated with specific metabolomic alterations of which the higher lipoprotein concentrations were likely contributed by larger adipocyte volumes, presumably linking weight gain to cardiometabolic disease. Show less
Winters-van Eekelen, E.; Verkouter, I.; Peters, H.P.F.; Alssema, M.; Roos, B.G. de; Schrauwen-Hinderling, V.B.; ... ; Mutsert, R. de 2020
Dietary macronutrient composition may affect hepatic liver content and its associated diseases, but the results from human intervention trials have been equivocal or underpowered. We aimed to... Show moreDietary macronutrient composition may affect hepatic liver content and its associated diseases, but the results from human intervention trials have been equivocal or underpowered. We aimed to assess the effects of dietary macronutrient composition on liver fat content by conducting a systematic review and meta-analysis of randomized controlled trials in adults. Four databases (PubMed, Embase, Web of Science, and COCHRANE Library) were systematically searched for trials with isocaloric diets evaluating the effect of dietary macronutrient composition (energy percentages of fat, carbohydrates, and protein, and their specific types) on liver fat content as assessed by magnetic resonance techniques, computed tomography or liver biopsy. Data on change in liver fat content were pooled by random or fixed-effects meta-analyses and expressed as standardized mean difference (SMD). We included 26 randomized controlled trials providing data for 32 comparisons on dietary macronutrient composition. Replacing dietary fat with carbohydrates did not result in changes in liver fat (12 comparisons, SMD 0.01 (95% CI -0.36; 0.37)). Unsaturated fat as compared with saturated fat reduced liver fat content (4 comparisons, SMD -0.80 (95% CI -1.09; -0.51)). Replacing carbohydrates with protein reduced liver fat content (5 comparisons, SMD -0.33 (95% CI -0.54; -0.12)). Our meta-analyses showed that replacing carbohydrates with total fat on liver fat content was not effective, while replacing carbohydrates with proteins and saturated fat with unsaturated fat was. More well-performed and well-described studies on the effect of types of carbohydrates and proteins on liver fat content are needed, especially studies comparing proteins with fats. Show less
Verkouter, I.; Mutsert, R. de; Smit, R.A.J.; Trompet, S.; Rosendaal, F.R.; Heemst, D. van; ... ; Noordam, R. 2020
Background: Body mass index (BMI)-associated loci are used to explore the effects of obesity using Mendelian randomization (MR), but the contribution of individual tissues to risks remains unknown.... Show moreBackground: Body mass index (BMI)-associated loci are used to explore the effects of obesity using Mendelian randomization (MR), but the contribution of individual tissues to risks remains unknown. We aimed to identify tissue-grouped pathways of BMI-associated loci and relate these to cardiometabolic disease using MR analyses.Methods: Using Genotype-Tissue Expression (GTEx) data, we performed overrepresentation tests to identify tissue-grouped gene sets based on mRNA-expression profiles from 634 previously published BMI-associated loci. We conducted two-sample MR with inverse-variance-weighted methods, to examine associations between tissue-grouped BMI-associated genetic instruments and type 2 diabetes mellitus (T2DM) and coronary artery disease (CAD), with use of summary-level data from published genome-wide association studies (T2DM: 74 124 cases, 824 006 controls; CAD: 60 801 cases, 123 504 controls). Additionally, we performed MR analyses on T2DM and CAD using randomly sampled sets of 100 or 200 BMI-associated genetic variants.Results: We identified 17 partly overlapping tissue-grouped gene sets, of which 12 were brain areas, where BMI-associated genes were differentially expressed. In tissue-grouped MR analyses, all gene sets were similarly associated with increased risks of T2DM and CAD. MR analyses with randomly sampled genetic variants on T2DM and CAD resulted in a distribution of effect estimates similar to tissue-grouped gene sets.Conclusions: Overrepresentation tests revealed differential expression of BMI-associated genes in 17 different tissues. However, with our biology-based approach using tissue-grouped MR analyses, we did not identify different risks of T2DM or CAD for the BMI-associated gene sets, which was reflected by similar effect estimates obtained by randomly sampled gene sets. Show less
Noordam, R.; Boersma, V.; Verkouter, I.; Cessie, S. le; Christen, T.; Lamb, H.J.; ... ; Mutsert, R. de 2020
Background and aims: In the present study, we assessed the extent of mediation by low-grade systemic inflammation and adipokines in the association between abdominal adiposity and insulin... Show moreBackground and aims: In the present study, we assessed the extent of mediation by low-grade systemic inflammation and adipokines in the association between abdominal adiposity and insulin resistance.Methods and results: In this cross-sectional analysis of baseline measurements of the Netherlands Epidemiology of Obesity study, total body fat (TBF) was measured in all (n = 5772) participants who did not have missing data and neither used glucose-lowering medication, and abdominal subcutaneous adipose tissue (aSAT) and visceral adipose tissue (VAT) were assessed by MRI in a random subgroup (n = 2448). C-reactive protein (CRP), adiponectin, and leptin were considered as potential mediators, and insulin resistance was assessed by Homeostatic Model Assessment of Insulin Resistance (HOMA-IR). Mediation by CRP, adiponectin, and leptin was studied by including the mediators to the fully adjusted linear regression model. Participants had a mean (SD) age of 56 (6) years, TBF of 36 (9) %, VAT of 119 (61) cm2 and aSAT of 300 (111) cm2. Per SD of TBF, VAT and aSAT, HOMA-IR was 64% (95% confidence interval [CI]: 59-70), 33% (95% CI: 28-42) and 20% (95%CI: 14-26) higher, respectively. The association between aSAT and HOMA-IR fully disappeared after adjustment for leptin; the association between VAT and HOMA-IR attenuated after adjustment for leptin (22%) and adiponectin (15%). No mediation was observed by CRP, and mediation estimates were similar in men and women.Conclusion: Where leptin fully explained the aSAT-HOMA-IR association, the VAT-HOMA-IR association was only partly explained by leptin and adiponectin similarly in men and women. (C) 2020 The Italian Diabetes Society, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved. Show less
Verkouter, I.; Noordam, R.; Cessie, S. le; Dam, R.M. van; Lamb, H.J.; Rosendaal, F.R.; ... ; Mutsert, R. de 2019