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PURPOSE: Individuals with severe liver disease are more vulnerable to severe COVID-19, but the association between chronic hepatitis B virus (HBV) infection and severe COVID-19 remains unclear. This study evaluates this relationship.

METHODS: We analysed nationwide Swedish data from national databases and healthcare registers, identifying laboratory-confirmed COVID-19 cases from February 2020 to April 2021. Chronic HBV infection was classified into cases with and without cirrhosis. Multivariable logistic regression assessed the association between HBV and severe COVID-19, adjusting for demographics, comorbidities, vaccination, and socioeconomic factors.

RESULTS: Among 1,057,174 COVID-19 cases, 2,902 had chronic HBV infection, which was associated with increased risk of severe COVID-19 (adjusted odds ratio [aOR] 1.242, 95% confidence interval [CI] 1.097-1.403). This risk was significantly higher in HBV individuals with cirrhosis (aOR 2.463, CI 1.546-3.892) compared to those without cirrhosis (aOR 1.183, CI 1.039-1.343). While overall COVID-19 mortality was not significantly elevated in the HBV cohort, patients with cirrhosis showed a higher, though nonsignificant, mortality risk (aOR 2.350, CI 0.921-5.203).

CONCLUSION: This nationwide study highlights an increased risk of severe COVID-19 in individuals with chronic HBV, particularly those with cirrhosis. Geographic and socioeconomic factors further influence outcomes. These findings underscore the need to consider HBV status in COVID-19 risk assessments. Future studies should explore these associations in the context of evolving SARS-CoV-2 variants and widespread vaccination.

Introduction: Little is known of the long-term prognosis of patients with acute ischaemic stroke in the absence of standard modifiable stroke risk factors (SMoRFs). In acute coronary syndromes, patients without modifiable risk factors have a higher mortality rate. We analysed data from the Swedish Stroke Register to determine survival of patients without SMoRFs following an ischaemic stroke.

Patients and methods: We identified adult patients with first-presentation acute ischaemic stroke between 2010 and 2020. Patients were considered to possess a SMoRF if they had one of: hypertension, diabetes, hyperlipidaemia, atrial fibrillation or an active smoking history. We compared mortality in patients with and without SMoRFs following first-presentation ischaemic stroke using cox regression models. We also assessed the combined endpoint death and dependency (mRS 3–6) at 3 months via logistic regression models.

Results: Of 152,588 patients with ischaemic stroke, hypertension (58.7%) and atrial fibrillation (27.3%) were the most common risk factors. 34,019 patients (22.3%) had no SMoRFs. After a first-presentation ischaemic stroke, patients without SMoRFs had a lower risk of death than patients with one or more SMoRFs (HR 0.58 [95% CI 0.57–0.59]). The absence of SMoRFs was associated with lower odds of death and dependency at 3 months in logistic regression models (OR 0·60 [95% CI 0.58–0.62]).

Conclusion: One in five patients with acute ischaemic stroke had no standard modifiable stroke risk factors. These patients have lower risk of death compared to patients with one or more SMoRFs.

Background and Aims: This study aimed to investigate the association between normal BP, (blood pressure [BP] 120–129/80–84 mmHg), and high normal BP, (BP 130–139/85–89 mmHg), compared to optimal BP, and risk of atrial fibrillation (AF).

Methods: A population-based cohort study was performed including inhabitants of Västerbotten County, Sweden, aged 30–60 years without AF at inclusion who participated in health examinations in 1988–2014. Approximately 40% of participants had ≥ 2 health examinations. The health examination included a questionnaire and measurement of BP, weight, height, and glucose. Cox regression with time-updated covariates was used to estimate the association between BP and AF risk. Restricted cubic spline analyses were performed.

Results: The cohort included 109,697 persons with 162,982 observations and a mean follow-up of 13.6 years. Incident AF was diagnosed in 5260 participants. We found an increased risk of incident AF associated with normal BP (hazard ratio [HR] 1.13, 95% confidence interval [CI] 1.01–1.27) and high normal BP (HR 1.23, 95% CI 1.10–1.38) compared to optimal BP after multivariable adjustment. Systolic BP and diastolic BP in 10 mmHg increments were associated with risk of incident AF, with HRs of 1.11 (95% CI 1.10–1.13) and 1.13 (95% CI 1.09–1.16), respectively, in multivariable models. A restricted cubic spline analysis indicated that the AF risk increased gradually with increasing systolic and diastolic BP.

Conclusion: Individuals with both normal BP and high normal BP have an increased risk of developing incident AF. The risk of AF increased gradually with increasing systolic and diastolic BP.

Aims: Doctors have an increased risk of SARS-CoV-2 infection caused by exposure to contagious patients. We aimed to identify which clinical specialities among medical doctors had the highest occupation-related risk of testing positive for SARS-CoV-2, utilizing data for all publicly employed medical doctors in Sweden.

Methods: Data regarding positive SARS-CoV-2 test results and employment for publicly employed doctors in Sweden were divided into three observation periods: 1) 1 February to 31 December 2020, 2) 1 January to 30 June 2021 and 3) 1 July 2021 to 31 March 2022. Individuals were stratified according to occupation clinic and compared with clinical occupations with little to no patient contact. The risk of testing positive for SARS-CoV-2 was estimated using Cox proportional hazards regression, with sex, age and vaccination status as covariates.

Results: The study cohort included all publicly employed doctors in Sweden: 35,028 individuals. In the first period, Infectious Disease doctors had the highest incidence of SARS-CoV-2 positive tests, with an incidence of 20.2 %, compared with 8.7 % in the reference group, and an adjusted hazard ratio of 2.5 (95% confidence interval 2.02–3.04), which decreased during period 2–3. Doctors in Geriatric Medicine had an elevated risk throughout the whole study period.

Conclusions: Our study shows an association between working in a speciality that involves caring for contagious COVID-19 patients, which raises concerns about infection control measures and routines being insufficient to prevent occupational infection in future pandemics.

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.

Background: Macrophages are involved in kidney transplants. The aim of the study was to investigate if changes exist in the levels of glomerular macrophage index (GMI) between two consecutive kidney transplant biopsies, and if so to determine their potential impact on graft survival.

Methods: Two consecutive biopsies were performed on the same renal graft in 623 patients. GMI was categorized into three GMI classes: ≤1.8 Low, 1.9–4.5 Medium, and ≥4.6 High. This division yielded nine possible switches between the first and second biopsies (Low-Low, Low-Medium, etc.). Cox-regressions were used and hazard ratios (HR) with 95% confidence interval (CI) are presented.

Results: The worst graft survival was observed in the High-High group, and the best graft survival was observed in the Low-Low and High-Low groups. Compared to the High-High group, a reduction of risk was observed in nearly all other decreasing groups (reductions between 65% and 80% of graft loss). After adjustment for covariates, the risk for graft-loss was lower in the Low-Low (HR = 0.24, CI 0.13–0.46), Low-Medium (HR = 0.25, CI 0.11–0.55), Medium-Low (HR = 0.29, CI 0.11–0.77), and the High-Low GMI (HR = 0.31, CI 0.10–0.98) groups compared to the High-High group as the reference.

Conclusions: GMI may change dynamically, and the latest finding is of most prognostic importance. GMI should be considered in all evaluations of biopsy findings since high or increasing GMI levels are associated with shorter graft survival. Future studies need to consider therapeutic strategies to lower or maintain a low GMI. A high GMI besides a vague histological finding should be considered as a warning sign requiring more frequent clinical follow up.

Globally, stroke is the third-leading cause of mortality and disability combined, and one of the costliest diseases in society. More accurate predictions of stroke outcomes can guide healthcare organizations in allocating appropriate resources to improve care and reduce both the economic and social burden of the disease. We aim to develop and evaluate the performance and explainability of three supervised machine learning models and the traditional multinomial logistic regression (mLR) in predicting functional dependence and death three months after stroke, using routinely-collected data. This prognostic study included adult patients, registered in the Swedish Stroke Registry (Riksstroke) from 2015 to 2020. Riksstroke contains information on stroke care and outcomes among patients treated in hospitals in Sweden. Prognostic factors (features) included demographic characteristics, pre-stroke functional status, cardiovascular risk factors, medications, acute care, stroke type, and severity. The outcome was measured using the modified Rankin Scale at three months after stroke (a scale of 0-2 indicates independent, 3-5 dependent, and 6 dead). Outcome prediction models included support vector machines, artificial neural networks (ANN), eXtreme Gradient Boosting (XGBoost), and mLR. The models were trained and evaluated on 75% and 25% of the dataset, respectively. Model predictions were explained using SHAP values. The study included 102,135 patients (85.8% ischemic stroke, 53.3% male, mean age 75.8 years, and median NIHSS of 3). All models demonstrated similar overall accuracy (69%-70%). The ANN and XGBoost models performed significantly better than the mLR in classifying dependence with F1-scores of 0.603 (95% CI; 0.594-0.611) and 0.577 (95% CI; 0.568-0.586), versus 0.544 (95% CI; 0.545-0.563) for the mLR model. The factors that contributed most to the predictions were expectedly similar in the models, based on clinical knowledge. Our ANN and XGBoost models showed a modest improvement in prediction performance and explainability compared to mLR using routinely-collected data. Their improved ability to predict functional dependence may be of particular importance for the planning and organization of acute stroke care and rehabilitation.

Aim: Speech difficulties are common in children with cleft palate, but research on foreign-born children is limited. This study aimed to compare speech outcomes, surgery and speech intervention in 5-year-old foreign-born and Swedish-born children with cleft palate with or without cleft lip.

Methods: This retrospective study analysed data from the Swedish cleft lip and palate registry for children born between 2009 and 2016 using Pearson's Chi-squared test and binary logistic regression.

Results: Among 160 foreign-born (106 boys, 54 girls) and 847 Swedish-born (479 boys, 368 girls) 5-year-olds, foreign-born children had significantly lower rates of sufficient velopharyngeal competence (77% vs. 86%), age-appropriate consonant production (28% vs. 60%), and speech without non-oral speech errors (70% vs. 86%). Differences remained after adjustment for cleft type, gender and additional diagnosed conditions. After further adjustments for age at completed primary palatal surgery, differences in age-appropriate consonant production and speech without non-oral speech errors remained significant. Foreign-born children underwent completed primary palatal surgery at older ages and received more secondary palatal surgery and speech intervention than Swedish-born peers.

Conclusion: Foreign-born children showed poorer speech outcomes than Swedish-born peers, despite more secondary palatal surgery and speech intervention. Age at completed primary palatal surgery could partly explain these differences.

Introduction: SARS-CoV-2 infection causes acute COVID-19 and may result in post-COVID syndrome (PCS). We aimed to investigate how clinicians diagnose PCS and identify associated clinical and demographic characteristics.

Methods: We analysed multiregistry data of all SARS-CoV-2 test-positive individuals in Sweden (n=1 057 174) between 1 February 2020 and 25 May 2021. We described clinical characteristics that prompt PCS diagnosis in outpatient and inpatient settings. In total, there were 6389 individuals with a hospital inpatient or outpatient diagnosis for PCS. To understand symptomatology, we examined individuals diagnosed with PCS at least 3 months after COVID-19 onset (n=6389) and assessed factors associated with PCS diagnosis.

Results: Mechanical ventilation correlated with PCS (OR 114.7, 95% CI 105.1 to 125.3) compared with no outpatient/inpatient contact during initial COVID-19. Dyspnoea (13.4%), malaise/fatigue (8%) and abnormal pulmonary diagnostic imaging findings (4.3%) were the most common features linked to PCS. We compared clinical features of PCS with matched controls (COVID-19 negative, n=23 795) and COVID-19 severity-matched patients (COVID-19 positive, n=25 556). Hypertension associated with PCS cohort (26.61%) than in COVID-19-negative (OR 17.16, 95% CI 15.23 to 19.3) and COVID-19-positive (OR 9.25, 95% CI 8.41 to 10.16) controls, although most individuals received this diagnosis before COVID-19. Dyspnoea was the second most common feature in the PCS cohort (17.2%), and new to the majority compared with COVID-19-negative (OR 54.16, 95% CI 42.86 to 68.45) and COVID-19-positive (OR 18.7, 95% CI 16.21 to 21.57) controls.

Conclusions: Our findings highlight factors Swedish physicians associate with PCS.

BACKGROUND: When more patients with congenital heart disease reach adult age, increased incidence of long-term complications, including ischemic stroke, are expected. The aim of this study was to analyze cumulative incidence of ischemic stroke, associated factors, and case fatality in adult congenital heart disease.

METHODS AND RESULTS: The study is based on Swedish national registers on congenital heart disease and stroke. Patients with congenital heart disease were followed between 2001 and 2018 for first-ever ischemic stroke events (ischemic stroke due to patent foramen ovale excluded). Factors possibly associated with ischemic stroke were analyzed using Cox regression models. Out of 8914 adult patients with congenital heart disease, 108 suffered ischemic stroke over a mean period of 7.6±4.7 years. The mean age at ischemic stroke was 53.8 years, and the cumulative incidence was 0.15% at 1 year, 0.5% at 5 years, and 1.5% at 10 years. In multivariable analysis, age (hazard ratio [HR], 1.04 [95% CI, 1.03-1.06]), diabetes (HR, 2.9 [95% CI, 1.3-6.4]), ejection fraction <50% (HR, 1.9 [95% CI, 1.1-3.4]), atrial septal defect (HR, 3.0 [95% CI, 1.03-8.5]), and aortic valve lesions (HR, 4.8 [95% CI, 1.6-14.1]) were associated with increased risk. Among those with ischemic stroke, approximately half were on antithrombotic treatment (anticoagulants or antiplatelets) before admission. Case fatality was 6.5%.

CONCLUSIONS: The cumulative incidence of ischemic stroke was 1.5% after 10 years. In adult congenital heart disease, the type of heart lesion, diabetes, ejection fraction <50%, and age were important factors associated with ischemic stroke. Despite a relatively young age, mortality is a significant threat. At time of the ischemic stroke event, approximately half of the patients were on antithrombotic treatment.