Impacts of the COVID-19 pandemic on deprivation-level differences in cardiovascular hospitalisations: a comparison of England and Denmark using the OpenSAFELY platform and National Registry Data.

Objectives: To examine the impact of the COVID-19 pandemic on deprivation-related inequalities in hospitalisations for cardiovascular disease (CVD) conditions in Denmark and England between March 2018 and December 2021.

Design: Time-series studies in England and Denmark.

Setting: With the approval of National Health Service England, we used English primary care electronic health records, linked to secondary care and death registry data through the OpenSAFELY platform and nationwide Danish health registry data.

The combined impact of migraine and gestational diabetes on long-term risk of premature myocardial infarction and stroke: A population-based cohort study.

Objective: To examine the combined impact of migraine and gestational diabetes mellitus (GDM) on the risks of premature (persons aged ≤60 years) major adverse cardiovascular and cerebrovascular events (MACCE) based on a composite endpoint of fatal and non-fatal myocardial infarction (MI) and stroke.

Background: Migraine and GDM are risk factors for cardiovascular disease. It is unknown how the combination of migraine and GDM may affect cardiovascular disease risk.

Excess Mortality Calculations to Assess the Impact of the COVID-19 Pandemic: Concepts and Methodological Issues.

We discuss some intriguing methodological aspects of excess mortality analyses, which have been widely used to describe the impact of the COVID-19 pandemic. We describe the main ways of presenting excess mortality: as a mortality rate (incidence rate) or as a percentage increase (relative risk or rate ratio). We discuss what should be regarded as the null value of excess mortality (i.

Correction: Migraine and risk of premature myocardial infarction and stroke among men and women: A Danish population-based cohort study.

[This corrects the article DOI: 10.1371/journal.pmed.

Report on the Joint Workshop on the Relations between Health Inequalities, Ageing and Multimorbidity, Iceland, May 3-4, 2023.

This paper is a summary of key presentations from a workshop in Iceland on May 3-4, 2023 arranged by Aarhus University and with participation of the below-mentioned scientists. Below you will find the key messages from the presentations made by: Professor Jan Vandenbroucke, Department of Clinical Epidemiology, Aarhus University, Emeritus Professor, Leiden University; Honorary Professor, London School of Hygiene & Tropical Medicine, UKProfessor, Chair Henrik Toft Sørensen, Department of Clinical Epidemiology, Aarhus University and Aarhus University Hospital, DenmarkProfessor David H. Rehkopf, Director, the Stanford Center for Population Health Sciences, Stanford University, CA.

Combined Impact of Migraine and Pregnancy-Induced Hypertension on Long-term Risk of Premature Myocardial Infarction and Stroke.

Background And Objectives: Migraine and pregnancy-induced hypertension (PIH) are known to increase cardiovascular risk on their own. However, evidence is limited on the combined impact of migraine and PIH on risk of cardiovascular disease. The aim of this study was to examine the combined impact of migraine and PIH on risk of premature (age 60 years and younger) major adverse cardiovascular and cerebrovascular events (MACCE), a composite end point consisting of myocardial infarction, stroke, or death due to one of these diseases.

Thromboembolic events, bleeding, and mortality in patients with cerebral venous thrombosis: a nationwide cohort study.

Cerebral venous thrombosis (CVT) predominantly affects young to middle-aged women. Scarce data exist regarding the long-term prognosis. We examined the clinical course of patients with CVT overall and according to their age and sex.

SARS-CoV-2 antibody persistence after five and twelve months: A cohort study from South-Eastern Norway.

Objectives: To assess total antibody levels against Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS CoV-2) spike protein up to 12 months after Coronavirus Disease (COVID-19) infection in non-vaccinated individuals and the possible predictors of antibody persistence.

Methods: This is the first part of a prospective multi-centre cohort study.

Participants: The study included SARS-CoV-2 real-time polymerase chain reaction (RT-PCR) positive and negative participants in South-Eastern Norway from February to December 2020.

Tipping Points - Do the Prognostic Values of Multimorbidity and Functional Status Vary with Age?

Aging of the population is a pressing challenge for healthcare systems and knowledge of a patient's prognosis is a key to shaping effective interventions. As the prevalence of multimorbidity strongly increases with age, the prognostic value of multiple disease diagnoses for survival among older people may diminish, whereas other measures of health, such as functional status (defined as a measure of an individual's ability to perform activities of daily living), may become more important. In this commentary, the impact of age on the prognostic value of multimorbidity is discussed, with the aim of identifying relevant alternative risk indicators for different age groups.

[Covid-19: excess deaths should be the outcome measure].

During the covid-19 pandemic there were large differences in excess deaths between high income countries, as shown in a study recently published in BMJ. The number of excess deaths gives a better estimate of the effects of covid-19 on mortality than the number of reported deaths from covid-19. This comment explains why and shows the consequences for the interpretation of Dutch mortality data.

Arguments about face masks and Covid-19 reflect broader methodologic debates within medical science.

There has perhaps been no issue as contentious in Covid-19 as face masks. The most contentious scientific debate has been between those who argue that "there is no scientific evidence", by which they mean that there are no randomized controlled trials (RCTs), versus those who argue that when the evidence is considered together, "the science supports that face coverings save lives". It used to be a 'given' that to decide whether a particular factor, either exogenous or endogenous, can cause a particular disease, and in what order of magnitude, one should consider all reasonably cogent evidence.

Community-Acquired Bacteremia after Age 50 and Subsequent Incidence of a Cancer Diagnosis: A Danish Population-Based Cohort Study.

Background: Community-acquired bacteremia (CAB) with may signal occult cancer. This might differ between phylogenetic groups.

Methods: We conducted a population-based cohort study in northern Denmark (1994-2013) to examine whether CAB after age 50 is associated with incident cancer.

A Test-Negative Design with Additional Population Controls Can Be Used to Rapidly Study Causes of the SARS-CoV-2 Epidemic.

Testing of symptomatic persons for infection with severe acute respiratory syndrome coronavirus-2 is occurring worldwide. We propose two types of case-control studies that can be carried out jointly in test settings for symptomatic persons. The first, the test-negative case-control design (TND) is the easiest to implement; it only requires collecting information about potential risk factors for Coronavirus Disease 2019 (COVID-19) from the tested symptomatic persons.

Educational note: types of causes.

We explore the different types of causes that are commonly investigated by epidemiologists. We first distinguish between causes which are events (including actions) and causes which are states. Second, we distinguish between modifiable and non-modifiable states.

Test-Negative Designs: Differences and Commonalities with Other Case-Control Studies with "Other Patient" Controls.

Test-negative studies recruit cases who attend a healthcare facility and test positive for a particular disease; controls are patients undergoing the same tests for the same reasons at the same healthcare facility and who test negative. The design is often used for vaccine efficacy studies, but not exclusively, and has been posited as a separate type of study design, different from case-control studies because the controls are not sampled from a wider source population. However, the design is a special case of a broader class of case-control designs that identify cases and sample "other patient" controls from the same healthcare facilities.

COSMOS-E: Guidance on conducting systematic reviews and meta-analyses of observational studies of etiology.

Background: To our knowledge, no publication providing overarching guidance on the conduct of systematic reviews of observational studies of etiology exists.

Methods And Findings: Conducting Systematic Reviews and Meta-Analyses of Observational Studies of Etiology (COSMOS-E) provides guidance on all steps in systematic reviews of observational studies of etiology, from shaping the research question, defining exposure and outcomes, to assessing the risk of bias and statistical analysis. The writing group included researchers experienced in meta-analyses and observational studies of etiology.

From ideas to studies: how to get ideas and sharpen them into research questions.

Where do new research questions come from? This is at best only partially taught in courses or textbooks about clinical or epidemiological research. Methods are taught under the assumption that a researcher already knows the research question and knows which methods will fit that question. Similarly, the real complexity of the thought processes that lead to a scientific undertaking is almost never described in published papers.

Effect modification, interaction and mediation: an overview of theoretical insights for clinical investigators.

We revisited the three interrelated epidemiological concepts of effect modification, interaction and mediation for clinical investigators and examined their applicability when using research databases. The standard methods that are available to assess interaction, effect modification and mediation are explained and exemplified. For each concept, we first give a simple "best-case" example from a randomized controlled trial, followed by a structurally similar example from an observational study using research databases.

Exposure Opportunity: The Advantages of Including Men in Analyses of Female-Related Risk Factors.

Intuitively, researchers do not include subjects who do not have the opportunity to be exposed, such as men in studies on oral contraceptives (OCs). We aimed to explore in which situations it is nevertheless beneficial to do so. We considered the effect of including men in case-control analyses of 8 different hypothetical data sets on the effect of OC use and venous thrombosis.

Confounding in observational studies based on large health care databases: problems and potential solutions - a primer for the clinician.

Population-based health care databases are a valuable tool for observational studies as they reflect daily medical practice for large and representative populations. A constant challenge in observational designs is, however, to rule out confounding, and the value of these databases for a given study question accordingly depends on completeness and validity of the information on confounding factors. In this article, we describe the types of potential confounding factors typically lacking in large health care databases and suggest strategies for confounding control when data on important confounders are unavailable.