Tor Biering-Sørensen

• MD, MSc, MPH, PhD
• Professor at University of Copenhagen

Background Studies suggest that clarithromycin is associated with an increased risk of major adverse cardiovascular events (MACE) among adults with coronary artery disease. However, data comparing clarithromycin to other macrolides, such as azithromycin, in a broader population are lacking. Methods A multicenter study was conducted in 33 hospitals...

(Abstracted from JAMA 2024;332(22):1900–1911 Globally, seasonal influenza causes up to 650,0000 respiratory deaths per year. Yet, vaccination rates remain low.

Objective Patients with chronic obstructive pulmonary disease (COPD) are a heavily comorbid group. Quinine is often used in the treatment of restless leg syndrome (RLS), although the adverse effects of the drug may be harmful for specific patient groups. The aim of this study was to determine the association between treatment with Quinine and the r...

Aims Metabolic dysfunction‐associated steatotic liver disease (MASLD) is associated with heart failure (HF), independent of shared risk factors. Our aim was to describe the incidence of HF in patients with biopsy‐proven MASLD. Methods and results We followed patients with biopsy‐proven MASLD from the prospective Duke NAFLD Biorepository and Clinic...

Objectives Erectile dysfunction (ED) is recognized as an early marker for cardiovascular disease yet the specific clinical characteristics that correlate with cardiac dysfunction remain unclear. We aimed to identify risk factors of cardiac dysfunction in men with ED. Methods In this cross-sectional study, men with ED were included from a Urology o...

Background Overweight/obesity are important risk factors for heart failure (HF), however, the pathophysiologic consequences of obesity in patients with acute HF (AHF) are incompletely understood. Methods We examined cardiac structure and function, and congestion-related markers in adults hospitalized for AHF across 3 body mass index (BMI) groups:...

Background Type 2 diabetes is a stronger risk factor for cardiovascular disease (CVD) in women compared with men possibly due to higher susceptibility to develop myocardial microvascular dysfunction. We investigated sex-dependent effects of risk factors on myocardial blood flow (MBF) and myocardial flow reserve (MFR) in individuals with type 2 diab...

Background: Vitamin K is a cofactor necessary for the biological activity of proteins like Matrix Gla Protein (MGP), which reduce calcification and help preserve lung function. This study aims to determine, first, whether low vitamin K status is associated with chronic obstructive pulmonary disease (COPD), and secondary, whether the level of vitami...

Cardiovascular and infectious diseases both feature among the leading causes of death among men and women in the world. The pathophysiological pathways of infection and cardiovascular disease intersect, and there is a bidirectional relationship between the two. Vaccines are available for the most common infectious diseases affecting older adults, s...

People with HIV (PWH) have a high risk of peripheral artery disease (PAD), and high-sensitivity troponin (hsTnT) and NT-pro B-type natriuretic peptide (NT-proBNP) may be useful biomarkers for PAD in PWH. We assessed associations between hsTnT and NT-proBNP and both prevalent PAD and de novo PAD. Adult PWH were examined at baseline and after 2 years...

This secondary analysis of a randomized clinical trial investigates whether electronic nudging letters to increase influenza vaccination have an effect on COVID-19 vaccination, infection, and hospitalization.

Background Extensive preclinical research aims to develop novel therapeutics for myocardial fibrosis (MF), a condition marked by collagen accumulation that impairs cardiac function. MF is particularly relevant in heart failure with preserved ejection fraction (HFpEF), a growing clinical challenge with limited treatment options. However, current met...

Background The optimal antithrombotic strategy following transcatheter aortic valve replacement (TAVR) remains controversial. Objectives The authors aimed to determine the safety and efficacy of various antithrombotic regimens in patients without an indication for anticoagulation following TAVR. Methods We conducted a systematic search in PubMed,...

Background Influenza infection has been associated with multiple cardiac complications including acute heart failure and myocardial infarction. The FluHeart study aims to uncover the potential effect of influenza infection on cardiac structure and function as assessed by echocardiography during hospitalization. Methods This prospective cohort stud...

BACKGROUND Use of anabolic androgenic steroids (AASs) is associated with increased mortality, and case reports have suggested that some of these deaths are due to cardiovascular disease. However, the epidemiology of cardiovascular disease in AAS users is still relatively unexplored. This study aimed to measure the incidence of cardiovascular diseas...

Background Iron deficiency (ID) is common in patients with atrial fibrillation/flutter (AF), but its prognostic implications and optimal diagnostic criteria, particularly in those with and without heart failure (HF), remain unclear. This study assessed the associations between different ID definitions and clinical outcomes in patients with AF. Met...

Importance Cardiovascular disease is the leading cause of death in the US. However, it remains unclear how the burden of cardiovascular events in the US compares with that of other high-income countries with distinct health care systems like Denmark, both overall and by income. Objective To compare cardiovascular hospitalization rates (acute myoca...

Background Patient-reported outcomes (PRO) and self-swab studies may offer to improve monitoring of infectious diseases. The DANFLU-2 HomeSwab PRO study aimed to assess the practicality of self-administered swabs and digital PRO tracking to monitor influenza-like illness (ILI). Methods As part of a sub-study of the DANFLU-2 trial, participants wer...

Importance. Cardiovascular and renal consequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been studied intensively in high-risk groups, but the consequences of mild infection for the general population, particularly beyond the acute phase of infection, remain unclear. Objective. To examine long-term associatio...

Background Myocardial work is a novel measure of potential value for diagnosing coronary artery disease (CAD). It may therefore be useful in patients with chronic kidney disease (CKD), in whom the diagnostic work‐up can be challenging. Methods This was a cross‐sectional study of patients with CKD (G1‐5, nondialysis‐dependent). Cardiac computed tom...

Chronic medical conditions caused by the inadequate adaptation of the body to modern lifestyles, such as physical inactivity and unhealthy diets, are on the rise. This study assessed whether a comprehensive lifestyle intervention, including high volumes of supervised exercise, could improve health outcomes. Eight volunteers with lifestyle‐related d...

Cardiac remodelling is a key determinant of worse cardiovascular outcome in patients with heart failure (HF) and reduced ejection fraction (HFrEF). It affects both the left ventricle (LV) structure and function as well as the left atrium (LA) and the right ventricle (RV). Guideline recommended medical therapy for HF, including angiotensin‐convertin...

Importance Influenza vaccination in patients with acute myocardial infarction (AMI) reduces major adverse cardiac events and is strongly recommended in clinical practice guidelines. Effective strategies to improve vaccination are needed in these high-risk patients. Objective To evaluate whether electronically delivered behavioral nudges improve in...

Background Despite evidence demonstrating that influenza vaccination is associated with reduced risk of cardiovascular events and all-cause mortality in individuals with diabetes mellitus (DM), vaccine uptake remains suboptimal. Objectives The purpose of this study was to assess the effectiveness of electronically delivered nudges on influenza vac...

Background: Hospitalizations due to heart failure (HF) are costly and detrimental to patient health. The HeartLogic (HL) algorithm has been found to be predictive of impending HF decompensation. Purpose: To present characteristics of the Danish nationwide DANLOGIC-HF population and preliminary findings on the performance of the HL algorithm. Method...

Introduction: Aging is associated with changes in left ventricular (LV) structure and function, and with increasing incidence of heart failure. However, little is known about longitudinal changes in LV systolic function in late life. Aim: To quantify changes in systolic function in late life. Methods: Among 2,779 participants in the community-based...

Background: Social determinants, such as educational attainment level (EAL), are indicators of socioeconomic status and have been shown to be inversely related with adverse health outcomes. However, the association between EAL and risk of cardio-pulmonary events in heart failure (HF) and myocardial infarction (MI) survivors has not been extensively...

Aims Iron deficiency (ID) is prevalent in chronic heart failure (HF) but lacks a consensus definition. This study evaluates the prevalence and the prognostic impact of ID using different criteria on all‐cause and cardiovascular mortality, as well as first hospitalization for HF in patients with new‐onset chronic HF. Methods In this nationwide regi...

Aims Heart failure ( HF ) is a leading cause of hospitalization, and sex differences in care have been described. We assessed sex‐specific clinical outcomes and healthcare resource utilization following hospitalization for HF. Methods and results This was an exploratory analysis of patients hospitalized for HF across 10 Canadian hospitals in the P...

Background: Cardiovascular complications are the leading cause of mortality in sickle cell anemia (SCA) patients. While cardiac diastolic dysfunction (DD) is a well-documented mechanism contributing to heightened morbidity and mortality, the unique hemodynamic conditions inherent to SCA pose challenges to the application of standard diastolic evalu...

Background Selected echocardiographic measures of cardiac structure and function are known to be associated with mortality in patients with Heart Failure with reduced Left Ventricular (LV) Ejection Fraction (HFrEF). Whether the predictive ability of measures of cardiac structure and function remain after implantation of an Implantable Cardioverter...

Background Left ventricular (LV) strain rate measures provide detailed information regarding LV contraction and filling pressures. These include global systolic strain rate (GSRs), early and late diastolic strain rates (GSRe and GSRa), and ratio of transmitral early filling velocity to GSRe (E/GSRe). Purpose To investigate the prognostic value of...

Background Left atrial (LA) volume dilatation is associated with stroke in the general population. Two-dimensional echocardiography (2DE) is commonly used to measure LA size but is known to underestimate LA volumes compared to three-dimensional echocardiography (3DE). It is unknown whether this difference has clinical significance. Purpose We hypo...

Background The role of the left atrium (LA) is increasingly recognized as a predictor of cardiovascular health outcomes. This study aimed to investigate the prognostic value of LA strain in relation to cardiovascular (CV) death in patients with heart failure (HF) with reduced ejection fraction (HFrEF). Methods In this retrospective cohort analysis...

Background Left ventricular mechanical dyssynchrony (LVMD) has shown to predict many cardiovascular outcomes including ventricular arrhythmias. Our hypothesis is that LVMD can reveal early atrial dysfunction. Purpose The aim of this study was to investigate whether LVMD can be used to predict atrial fibrillation (AF) and adverse outcomes following...

Background Left atrial (LA) strain measured by three-dimensional (3D) echocardiography (3DE) is a novel way of evaluating LA function. The prognostic value of LA strain by 3DE in incident heart failure (HF) and cardiovascular (CV) death has not previously been documented. Purpose We south to investigate whether 3D LA strain measures were associate...

Background Hypertension is associated with cardiac structural and functional changes, with left ventricular hypertrophy and diastolic dysfunction as strong predictors of adverse cardiac events. Limited data exist on how cardiovascular (CV) risk factors accelerate left ventricular (LV) mass and diastolic dysfunction over time in older hypertensive p...

Background Influenza virus may cause severe infection in patients with heart failure. It is accepted that influenza infection is associated with increased morbidity and mortality in patients with heart failure. However, less is known about the excess burden of morbidity and mortality caused by influenza infection in patients with heart failure at a...

Background B-lines by lung ultrasound (LUS) are associated with left ventricular (LV) dysfunction and may be useful for diagnostics in resource-limited settings. Purpose To assess the incidence of LV dysfunction in the general population of the Amazon Basin and to evaluate the diagnostic potential of LUS. We defined LV dysfunction as LV ejection f...

Background Cystic fibrosis (CF) is an autosomal recessive disease affecting multiple organs. Emerging evidence indicates an elevated risk of cardiovascular complications in people with CF (pwCF), with some studies implicating CF-related cardiomyopathy as an underlying mechanism. Whether screening for cardiac symptoms and N-terminal pro B-type natri...

Background The use of glucagon-like peptide-1 receptor agonsists (GLP-1 RA) continues to rise and is increasingly important in the treatment of type-2 diabetes mellitus (T2DM). Though the use of GLP-1 RA continues to increase, persistence and adherence to therapy remains suboptimal. Purpose We aimed to assess the level of adherence and persistence...

Background Chronic obstructive pulmonary disease (COPD) is common and strongly associated with cardiovascular disease, but the pathophysiology has not been fully elucidated. Purpose We aimed to investigate cardiac structure and function in patients with COPD compared to a matched general population. Methods In a prospective cohort study, 796 pati...

Background Cystic fibrosis (CF) is an autosomal recessive disease affecting multiple organs, however the extent of cardiac involvement in CF is yet to be determined. The remarkable therapeutic advancements with new highly effective CF transmembrane conductance regulator (CFTR) modulator treatment and subsequent increase in life expectancy substanti...

Background Morbidity and mortality from influenza and cardiovascular disease occur frequently in persons with chronic kidney disease (CKD). Limited data exist on the effectiveness of high-dose influenza vaccination in persons with CKD. Purpose To assess the relative effectiveness of high-dose quadrivalent influenza vaccine (QIV-HD) vs. standard-do...

Background Frailty is a major risk factor for adverse cardiovascular events. Influenza vaccination has been shown to protect against cardiovascular fatal and nonfatal events. However, limited data exist on the added benefit of high-dose versus standard-dose influenza vaccination according to frailty status. Purpose We sought to assess the relative...

Background Emerging evidence indicates the coexistence pulmonary fibrosis and emphysema in patients with Chronic Obstructive Pulmonary Disease (COPD). The effect of pulmonary fibrosis on cardiac structure and function in COPD patients remains unclear. Purpose This study aimed to examine the association between the degree of pulmonary fibrosis iden...

Introduction Iron deficiency (ID) is prevalent in chronic heart failure (HF) but lacks a consensus definition. Purpose This study evaluates the prevalence of ID and its association with all-cause mortality and first hospitalization for HF, using current European Society of Cardiology (ESC) guidelines, transferrin saturation (TSAT) <20%, ferritin <...

Background Lipoprotein(a) [Lp(a)] is a genetically determined risk factor for myocardial infarction and aortic valve stenosis, and elevated Lp(a) levels are associated with increased risk of heart failure. While part of this heart failure risk is mediated through atherosclerotic and valvular disease, other pathological pathways may also contribute...

Background Human Immunodeficiency Virus (HIV) has become a treatable, chronic condition, but people with HIV still face an elevated risk of cardiovascular disease, including heart failure. Purpose To assess echocardiographic alterations in left ventricular (LV) function in a contemporary cohort of well-treated people with HIV compared to the gener...

Background The results of the DANFLU-1 trial indicated that high-dose quadrivalent influenza vaccines (HDQIV) as compared to standard-dose quadrivalent influenza vaccines (SDQIV) may reduce the incidence of death and hospitalization with pneumonia or influenza in older adults. Whether this effect differs by the presence of cardiovascular disease is...

Background Circadian variations have been shown to affect antibody response following vaccination. We sought to evaluate whether time of day of vaccination (ToV) modified the relative effectiveness of high-dose (QIV-HD) vs. standard-dose (QIV-SD) quadrivalent influenza vaccination, and further whether ToV was independently associated with hospitali...

Background Heart failure (HF) a leading cause of hospitalization, and sex differences in care have been described. Purpose We assessed sex-specific clinical outcomes and healthcare resource utilization following hospitalization for HF. Methods This was an exploratory analysis of patients hospitalized for HF across 10 Canadian hospitals enrolled i...

Background Annual influenza vaccination is recommended for individuals with chronic kidney disease (CKD); however, guideline adherence is suboptimal potentially related to lack of awareness of vaccine availability and effectiveness. Purpose This prespecified analysis of the NUDGE-FLU-CHRONIC trial investigated the effectiveness of digital behavior...

Background Emerging evidence suggests that the pathogenesis of atrial fibrillation (AF) is affected by inflammatory processes which contribute to structural and electrical remodeling of the atria, creating a substrate for arrythmia. Aim To assess whether inflammation measured by C-reactive protein (CRP) is associated with readmission for direct cu...

Background Despite evidence demonstrating that influenza vaccination is associated with reduced risk of adverse cardiovascular events and all-cause mortality, influenza vaccine uptake remains suboptimal in persons with diabetes mellitus (DM). Purpose In this prespecified analysis of the NUDGE-FLU-CHRONIC trial we assessed the effectiveness of elec...

Background Inflammation as an underlying cause of cardiac dysfunction has been underscored in recent years. Patients with inflammatory arthritis (IA) are at risk of being exposed to a high degree of chronic and systemic inflammation. It is therefore important to investigate whether high inflammatory burden impacts cardiac structure and function in...

Abuse of androgenic anabolic steroids (AAS) is associated with a range of cardiovascular side effects, summarized in this review. Apart from being linked to cardiovascular risk factors such as hypertension and dyslipidaemia, AAS abuse is associated with coronary atherosclerosis and imparts a pro-coagulative state, predisposing to thromboembolic dis...

Importance Despite strong worldwide guideline recommendations, influenza vaccination rates remain suboptimal among young and middle-aged patients with chronic diseases. Effective scalable strategies to increase vaccination are needed. Objective To investigate whether electronically delivered letter-based nudges informed by behavioral science could...

Background Extra-fine particle inhaled corticosteroids (ICS) improve peripheral airway distribution, but their effect on risk of exacerbations and all-cause mortality in patients with chronic obstructive pulmonary disease (COPD) is unclear. Methods This observational cohort study compares patients with COPD who received extra-fine particle ICS to...

Background Chronic obstructive pulmonary disease (COPD) and asthma can be treated with inhaled corticosteroids (ICS) delivered by low climate impact inhalers (dry powder inhalers) or high climate impact inhalers (pressurized metered-dose inhalers containing potent greenhouse gasses). ICS delivered with greenhouse gasses is prescribed ubiquitously a...

Background and aims Overtesting of low-risk patients with suspect chronic coronary syndrome (CCS) is widespread. The acoustic-based coronary artery disease (CAD) score has superior rule-out capabilities when added to pre-test probability (PTP). FILTER-SCAD tested whether providing a CAD score and PTP to cardiologists was superior to PTP alone in li...

Background: Influenza vaccination reduces the risk of adverse outcomes in patients with cardiovascular disease (CVD). We sought to evaluate whether the presence of CVD modified the relative effectiveness of high-dose (QIV-HD) vs. standard-dose (QIV-SD) quadrivalent influenza vaccine in this prespecified analysis of the DANFLU-1 trial. Methods: DANF...

Aims To assess the level of adherence to glucagon‐like peptide‐1 receptor agonist (GLP‐1RA) treatment using real‐world data and to investigate the sociodemographic and clinical factors associated with discontinuation of GLP‐1RAs. Methods First‐time users of GLP‐1RAs with type 2 diabetes mellitus (T2DM), aged ≥18 years, in the period 2007 to 2020,...

Digital letter interventions have proven effective in increasing influenza vaccination rates. In this trial, we sought to further refine these strategies and investigated whether the effectiveness of the strategies could be sustained across consecutive influenza seasons. We enrolled all eligible Danish citizens 65 years of age or older in a nationw...

Background In Canada, one in seven adults has diabetes (i.e., 2.3 million) and the lifetime risk of developing diabetes is approximately 30% by age 65. Although 30% of patients admitted to the hospital have diabetes, data from inpatient hospitalizations for patients with diabetes are lacking, both in Canada and globally. Objective To validate Inte...

Objectives Whether vaginal estradiol use is associated with an increased risk of recurrent venous thromboembolism (VTE) in women with prior VTE is unknown. We sought to evaluate the association between vaginal estradiol use and recurrent VTE in women with prior VTE. Methods We performed a nationwide nested case–control study among 44 024 women age...

Rationale Long-acting muscarinic antagonists (LAMAs) reduce the risk of acute exacerbations of chronic obstructive pulmonary disease (AECOPD), usually taken once daily in the morning. However, the circadian activity of autonomic regulation suggests that the highest need for anticholinergic therapy may be in the late night/early morning. This is sup...

Background Cardiac time intervals are sensitive markers of myocardial dysfunction that predispose to heart failure (HF). We aimed to investigate the association between cardiac time intervals and HF in patients with acute coronary syndrome (ACS). Methods This study included 386 ACS patients treated with percutaneous coronary intervention (PCI). Pa...