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Imaging-defined atherosclerosis represents an intermediate phenotype of atherosclerotic cardiovascular disease (ASCVD). Genome-wide association studies (GWAS) on directly measured coronary plaques using coronary computed tomography angiography (CCTA) are scarce. In the so far largest population-based cohort with CCTA data, we performed a GWAS on coronary plaque burden as determined by the segment involvement score (SIS) in 24,811 European individuals. We identified 20 significant independent genetic markers for SIS, three of which were found in loci not implicated in ASCVD before. Further GWAS on coronary artery calcification showed similar results to that of SIS, whereas a GWAS on ultrasound-assessed carotid plaques identified both shared and non-shared loci with SIS. In two-sample Mendelian randomization studies using SIS-associated markers in UK Biobank and CARDIoGRAMplusC4D, one extra coronary segment with atherosclerosis corresponded to 1.8-fold increased odds of myocardial infarction. This GWAS data can aid future studies of causal pathways in ASCVD.

Background: Aortic valve calcification (AVC) is an underlying pathophysiological mechanism in aortic stenosis, which shares many risk factors with diabetes. However, the association between dysglycemia and early stages of AVC remains unclear. The aim was to examine the associations between stages of dysglycemia and signs of AVC among middle-aged individuals from the general population.

Methods: This was a cross-sectional study from the Swedish CArdioPulmonary bioImage Study (SCAPIS) randomly enrolling 30,154 middle-aged men and women from six study sites in Sweden between 2013 and 2018. Glycemic status was based on the World Health Organization criteria (fasting blood glucose and/or HbA1c) and questionnaire-based answers on previous diseases and categorized as normoglycemia, prediabetes, newly detected diabetes and known diabetes. AVC was assessed on cardiac computed tomography (CT) and defined as evident or not.

Results: Of 29,331 individuals with data on glycemic status and AVC available, mean age was 57.5 years and normoglycemia was present in 76%, prediabetes in 16%, newly detected diabetes in 3% and known diabetes in 5%. The prevalence of AVC increased progressively across glycemic categories, particularly in males (8%, 11%, 14% and 17%; P < 0.01) compared to females (5%, 6%, 8% and 9%; P < 0.01). There was an association with AVC already in the early stages of dysglycemia; prediabetes (OR 1.16, 95% CI 1.02–1.31), newly detected diabetes (1.34 [1.05–1.71]) and known diabetes (1.61 [1.34–1.93]) after adjusting for age, sex, smoking, study site, low density lipoprotein-cholesterol and hypertension.

Conclusions: In this large, contemporary, and randomly selected population of middle-aged individuals, prediabetes, newly detected diabetes and known diabetes were all associated with CT-detected AVC. Further studies are warranted to investigate if managing dysglycemia, even in its early stages, may help slow down AVC progression.

Background: It has been hypothesized but seldom tested that the winter excess in cardiovascular disease (CVD) is related to hypovitaminosis D. The present study examined the association between CVD and (i) seasonality of 25-hydroxyvitamin D (25[OH]D) and (ii) individual 25(OH)D concentrations.

Methods and findings: Harmonized 25(OH)D data were obtained from the Biomarkers for Cardiovascular Risk Assessment in Europe (BiomarCaRE) project, including 79,570 participants examined between 1984 and 2010. One 25(OH)D measurement was available per participant. Primary endpoints were CVD incidence (coronary heart disease or stroke; n = 6006) and CVD mortality (n = 2985). To study (i), Poisson regression-derived rate ratios were compared according to two-month categories, ordered by baseline 25(OH)D concentrations. To study (ii), Cox regression-derived hazard ratios were compared according to quarters of baseline 25(OH)D concentrations. With respect to (i), despite a median 25(OH)D concentration ratio of 1:1.79, the trough months of 25(OH)D in March and April had a similar CVD incidence as the peak months of 25(OH)D in August and September (rate ratio: 1.07, 95% CI: 0.98–1.17). CVD mortality was slightly higher in the trough months compared to the peak months (rate ratio: 1.27, 95% CI: 1.12–1.44) but not compared to the other months (despite median 25[OH]D concentration ratios up to 1:1.62; p ≥ 0.077). The CVD mortality peak in January preceded the 25(OH)D trough, not adhering to the temporality criterion of Bradford Hill. With respect to (ii), compared to the lowest quarter, the highest quarter of 25(OH)D was associated with lower CVD incidence (hazard ratio: 0.82, 95% CI: 0.76–0.89) and CVD mortality (hazard ratio: 0.64, 95% CI: 0.57–0.72).

Conclusion: The present study does not support the hypothesis that seasonal increases in CVD are driven by short-term reductions in 25(OH)D. As in most observational studies, higher 25(OH)D concentrations were inversely associated with CVD.

Key features: 

• The Northern Sweden Health and Disease Study (NSHDS) was initiated in the mid-1980s. The NSHDS is a population-based prospective longitudinal cohort comprising >140 000 participants in the two northernmost regions in Sweden, Norrbotten and Västerbotten, with >240 000 blood samples and 1.5 million person-years of follow-up.
• The NSHDS includes three sub-cohorts: the Västerbotten Intervention Programme (VIP), the expanded Northern Sweden Monitoring of Trends and Determinants of Cardiovascular Disease (MONICA) Study, and the Mammography Screening Project (MSP). The VIP is both a community-based cardiometabolic intervention programme encouraging healthy lifestyle (targeting individuals 40, 50, and 60 years of age), and a corresponding research cohort. The MONICA is an observational study focusing on cardiovascular disease and its associated risk factors, recruiting individuals aged 25–74 years. The MSP recruited women attending mammography during 1995–2006. The NSHDS median participation age is 50 years (53% women).
• Most participants contribute data on health, lifestyle, anthropometric measures, blood pressure, blood lipids, and glucose tolerance, along with research blood samples that are fractionated, frozen within an hour of collection, and stored at –80°C. Linkage to registries, clinical cohorts, and biological tissue archives facilitates studies of well-characterized participants (often combined with intervention studies).
• Collaborations are encouraged. Additional information can be found at: info.brs@umu.se; https://www.umu.se/en/biobank

Background: In pulmonary arterial hypertension (PAH), comparative assessment of treatment effect on survival in randomized controlled settings of contemporary patients has not been feasible.

Objective: The aim of this study was to use EXPOSURE, the ongoing, real-world, post-authorization safety study, and commitment to the European Medicines Agency to perform pre-specified comparative survival analyses between patients that newly initiated selexipag versus other PAH-specific therapies by applying statistical methods to account for population differences.

Methods: EXPOSURE (EUPAS19085) is an observational study comprising patients with PAH who initiated selexipag or other PAH-specific therapy. To balance characteristics of patients in the other PAH therapy cohort with the selexipag cohort at PAH therapy initiation (baseline), propensity score weighting was applied. Mortality rate ratios (MRRs) were calculated.

Results: 2014 patients were available for analysis. Prior to applying propensity score weighting, patients in the selexipag cohort were more likely to have longer time from diagnosis, less functional impairment, and treatment with combination background therapy versus the other PAH therapy cohort. Following weighting, baseline variables for both cohorts were well balanced. Weighted treatment exposure was 827.9 and 840.5 person-years for the selexipag and modelled other PAH therapy cohort, respectively. Weighted proportion of deaths was lower in the selexipag versus modelled other PAH therapy cohort; MRR showed a higher survival rate for selexipag-treated patients (MRR [95% confidence interval]: 0.55 [0.31–0.99]).

Conclusions: Survival analyses in EXPOSURE suggest a reduced risk of mortality among the cohort of patients newly initiated on selexipag compared with the modelled cohort newly initiated with other PAH-specific therapies. Further research is needed to confirm this observation.

Trial Registry: Trial registration: EUPAS19085.

Background: Dyslipidaemia in patients with diabetes contributes to the risk of atherosclerotic cardiovascular disease. We aimed to identify a dyslipidemic profile associated with both dysglycemia and subclinical coronary atherosclerosis.

Methods: Study participants (n = 5050) were classified in three groups: normoglycemia, pre-diabetes, and diabetes. A coronary artery calcium score (CACS) > 0 defined subclinical coronary atherosclerosis. Two independent methods were used to identify, among 225 lipid biomarkers, those that were associated with pre-diabetes and diabetes and were further tested for association by zero inflated Poisson regression with CACS and with CACS burden in study participants with CACS>0. Estimates were adjusted for cardiovascular risk factors with an interaction term for dispensed lipid lowering drugs.

Results: Thirty-two biomarkers associated with prediabetes and diabetes were further investigated for association with CACS. HDL diameter [multi-adjusted OR of 0.85 and 95 %CI (0.78–0.92)] as well as free cholesterol, phospholipids and total lipids in extra large HDL were inversely associated with CACS. There was a borderline significant interaction between small HDL and dispensed lipid lowering drugs on the presence of CACS, with and multi-adjusted OR of 0.53 and 95 %CI (0.36–0.77). None of the 32 glycemic profile-related lipid biomarkers associated with the relative increase of CACS in those with CACS>0. No consistent association was observed between non-HDL lipoproteins and CACS.

Conclusions: Changes in composition and relative concentration of HDL associated with both dysglycemia and subclinical coronary atherosclerosis. Treatment with lipid lowering drugs may contribute to reduce the risk associated with high circulating levels of small HDL.

INTRODUCTION: The prevalence of type 2 diabetes (T2D) within sub-Saharan Africa (SSA) is increasing. Despite the pathophysiology of T2D differing by ethnicity and sex, risk stratification and guidelines for the prevention of T2D are generic, relying on evidence from studies including predominantly Europeans. Accordingly, this study aims to develop ethnic-specific and sex-specific risk prediction models for the early detection of dysglycaemia (impaired glucose tolerance and T2D) to inform clinically feasible, culturally acceptable and cost-effective risk management and prevention strategies using dietary modification in SSA and European populations.

METHODS AND ANALYSIS: This multinational collaboration will include the prospective cohort data from two African cohorts, the Middle-Aged Soweto Cohort from South Africa and the Research on Obesity and Diabetes among African Migrants Prospective cohort from Ghana and migrants living in Europe, and a Swedish cohort, the Pre-Swedish CArdioPulmonary bioImage Study. Targeted proteomics, as well as targeted and untargeted metabolomics, will be performed at baseline to discover known and novel ethnic-specific and sex-specific biomarkers that predict incident dysglycaemia in the different longitudinal cohorts. Dietary patterns that explain maximum variation in the biomarker profiles and that associate with dysglycaemia will be identified in the SSA and European cohorts and used to build the prototypes for dietary interventions to prevent T2D. A comparative cost-effectiveness analysis of the dietary interventions will be estimated in the different populations. Finally, the perceptions of at-risk participants and healthcare providers regarding ethnic-specific and sex-specific dietary recommendations for the prevention of T2D will be assessed using focus group discussions and in-depth interviews in South Africa, Ghana, Germany (Ghanaian migrants) and Sweden.

ETHICS AND DISSEMINATION: Ethical clearance has been obtained from all participating sites. The study results will be disseminated at scientific conferences and in journal publications, and through community engagement events and diabetes organisations in the respective countries.

Background: Lifestyle affects the risk of cardiovascular events such as myocardial infarction and stroke. Several lifestyle factors, such as physical activity (PA), are modifiable, and in this study, we examined the association between leisure-time PA habits and the risk of a first-ever stroke.

Methods: This prospective study included residents in Västerbotten, Sweden, who participated in the Västerbotten Intervention Programme at 40, 50, and 60 years of age. Altogether, 31,855 individuals (50.5% women, mean age: 42.6 [6.9] y at baseline) participated between 1989 and 2016. Leisure-time PA was categorized as irregular (never/now and then) or regular (once a week/2 or 3 times a week/more than 3 times a week). Changes in PA were compared between examinations (10 y apart). Cases of stroke were validated according to World Health Organization MONICA (Monitoring Trends and Determinants of Cardiovascular Disease) criteria. The risk related to changes in leisure-time PA was estimated using a multivariable Cox regression model.

Results: During an average follow-up of 9.8 years (4.4), 609 incident first-ever stroke cases occurred (1.9%). A multivariable model showed that, compared with individuals with irregular PA at both examinations, those reporting regular PA over time had a lower risk of stroke (hazard ratio: 0.78, 95% CI, 0.61–0.99).

Conclusion: Middle-aged adults who maintained regular PA during their leisure time over 10 years had a lower risk of a first-ever stroke. This association is probably partly mediated by lower body mass index and a reduced risk of hypertension and diabetes.

Aims: Helicobacter pylori (H. pylori) and its cytotoxin-associated gene A (CagA) have been associated with myocardial infarction (MI), but existing data are conflicting possibly due to limitations in study designs and lack of data on important confounders. The aim of this study was to determine whether H. pylori or CagA seropositivity is associated with incident MI, including MI phenotypes, and to describe temporal trends.

Methods: We used the Northern Sweden Health and Disease study, a prospective biobank with data from residents enrolled in a population-based cohort from health examinations between 1986 and 2006. A total of 826 first time MI cases with available blood samples from their index health examination were identified up to 2006. Each case was 1:2 matched with controls by age, sex, sample date and geographical area. Blood samples were analysed using ELISA to determine seroprevalence of H. pylori and CagA, which were then used to study the association with incident MI.

Results: The median age at baseline was 50 years, and 71% of participants were male. Seroprevalence of H. pylori and CagA was 46.5% and 32.1% in cases, respectively, compared to 43.7% and 30.6% in controls. Overall, H. pylori prevalence decreased over the study period. After multivariable adjustments, no significant association was observed between H. pylori seropositivity and incident MI (odds ratio: 1.15, 95% CI 0.94–1.42) nor between CagA-positive H. pylori and incident MI.

Conclusion: In a Swedish population-based cohort, no significant association was observed between H. pylori or CagA seropositivity and incidence of MI.

Objectives: The adipocyte-derived hormone leptin has been associated with the pathogenesis of cardiovascular disease. The mechanisms underlying this association are unclear but may relate to effects on the vascular endothelium. Our aim was to explore the effects of leptin on endothelial vasomotor and fibrinolytic function in healthy volunteers and patients with coronary artery disease.

Design: The vascular effects of leptin were assessed infusing recombinant human leptin in healthy volunteers during measuring vasomotor response by venous occlusion plethysmography. Additionally, circulating levels of leptin were analysed in relation to endothelial dysfunction in patients with established coronary artery disease.

Results: In healthy male volunteers, intra-arterial infusion of recombinant human leptin (80, 800 and 8,000 ng/min; n = 10) did not affect basal forearm blood flow, plasma tissue plasminogen activator (tPA) or plasminogen activator inhibitor type 1 concentrations (all p > 0.05). However, during concomitant co-infusion with leptin (800 ng/min; n = 10), drug-induced vasodilatation was reduced (p = 0.001), and tPA activity increased (p = 0.002). In patients with coronary artery disease, those with the high plasma leptin levels had reduced drug-induced vasodilatation (p < 0.001), and increased net release of tPA antigen and activity (p < 0.001 and p = 0.03, respectively) compared to those with low levels. The study has been registered retrospectively at Clinical Trials with number NCT04374500.

Conclusion: Intrabrachial leptin infusion did not affect the basal vascular tone, whereas acute and chronic hyperleptinemia was associated with blunted vasoreactivity in healthy volunteers, and in patients with coronary artery disease.