Association Between Sensitization and Insulin Resistance Among US Adults Screened for Type 2 Diabetes Mellitus.

Background: Type 2 diabetes mellitus (T2DM) may be a long-term sequela of infection with () by mechanisms that remain to be fully explained. We evaluated the association between sensitization and T2DM and, via mediation analysis, the extent to which it is mediated by insulin resistance and/or β-cell failure.

Methods: Adults were assessed for T2DM by fasting plasma glucose, 2-hour oral glucose tolerance testing, and hemoglobin A; β-cell dysfunction and insulin resistance by homoeostasis model assessment 2; and sensitization by tuberculin skin testing.

Subclinical Myocardial Fibrosis in South African Youth With HIV: Results From the CTAAC-Heart Study.

Background: Few data exist on myocardial fibrosis and inflammation in youth with HIV.

Methods: We performed cardiovascular magnetic resonance (CMR) on a cross section of South African youth: youth with perinatally acquired HIV (YPHIV) undergoing antiretroviral therapy (ART), youth with nonperinatally acquired HIV (YNPHIV) receiving ART, and youth without HIV. Quantile regression models were fit to assess the association between HIV status and CMR outcomes: subclinical fibrosis (late gadolinium enhancement [LGE] mass and fraction, native T1, extracellular volume) and inflammation (native T1, T2 mapping).

Clinical Characteristics and Mechanisms of Acute Myocarditis.

URL: https://www.clinicaltrials.gov; Unique identifier: NCT05335928.

Cardioprotective effects of early versus late initiated antiretroviral treatment in adolescents with perinatal HIV-1 infection.

Whether, and how, cardioprotective effects of antiretroviral treatment (ART) in adolescents with perinatal HIV infection (APHIV) vary with age at treatment initiation is unknown. We used magnetic resonance imaging to compare cardiac status between APHIV initiated on ART at < 5 years of age (early ART, n = 37) and ≥ 5 years of age (delayed ART, n = 34) versus HIV-uninfected peers (n = 21), reporting z-score mean differences adjusted for confounders. Relative to HIV-uninfected adolescents, APHIV with early ART had higher left ventricular (LV) global circumferential strain (GCS) [adjusted mean (95%CI) z-score: 0.

Scan With Me: A Train-the-Trainer Program to Upskill MRI Personnel in Low- and Middle-Income Countries.

Purpose: Access to MRI in low- and middle-income countries (LMICs) remains among the poorest in the world. The lack of skilled MRI personnel exacerbates access gaps, reinforcing long-standing health disparities. The Scan With Me (SWiM) program aims to sustainably create a network of highly skilled MRI technologists in LMICs who will facilitate the transfer of MRI knowledge and skills to their peers and contribute to the implementation of highly valuable imaging protocols for effective clinical and research use.

A study protocol to characterise pathophysiological and molecular markers of rheumatic heart disease and degenerative aortic stenosis using multiparametric cardiovascular imaging and multiomics techniques.

Introduction: Rheumatic heart disease (RHD), degenerative aortic stenosis (AS), and congenital valve diseases are prevalent in sub-Saharan Africa. Many knowledge gaps remain in understanding disease mechanisms, stratifying phenotypes, and prognostication. Therefore, we aimed to characterise patients through clinical profiling, imaging, histology, and molecular biomarkers to improve our understanding of the pathophysiology, diagnosis, and prognosis of RHD and AS.

Greater Disease Severity and Worse Clinical Outcomes in Patients Hospitalised with COVID-19 in Africa.

Background: COVID-19 cardiovascular research from Africa is limited. This study describes cardiovascular risk factors, manifestations, and outcomes of patients hospitalised with COVID-19 in the African region, with an overarching goal to investigate whether important differences exist between African and other populations, which may inform health policies.

Methods: A multinational prospective cohort study was conducted on adults hospitalised with confirmed COVID-19, consecutively admitted to 40 hospitals across 23 countries, 6 of which were African countries.

Distinct T cell polyfunctional profile in SARS-CoV-2 seronegative children associated with endemic human coronavirus cross-reactivity.

SARS-CoV-2 infection in children typically results in asymptomatic or mild disease. There is a paucity of studies on SARS-CoV-2 antiviral immunity in African children. We investigated SARS-CoV-2-specific T cell responses in 71 unvaccinated asymptomatic South African children who were seropositive or seronegative for SARS-CoV-2.

Changing character and waning impact of COVID-19 at a tertiary centre in Cape Town, South Africa.

Background: The emergence of genetic variants of SARS-CoV-2 was associated with changing epidemiological characteristics throughout coronavirus disease 2019 (COVID-19) pandemic in population-based studies. Individual-level data on the clinical characteristics of infection with different SARS-CoV-2 variants in African countries is less well documented.

Objectives: To describe the evolving clinical differences observed with the various SARS-CoV-2 variants of concern and compare the Omicron-driven wave in infections to the previous Delta-driven wave.

Homologous Ad26.COV2.S vaccination results in reduced boosting of humoral responses in hybrid immunity, but elicits antibodies of similar magnitude regardless of prior infection.

The impact of previous SARS-CoV-2 infection on the durability of Ad26.COV2.S vaccine-elicited responses, and the effect of homologous boosting has not been well explored.

The Determinants of Elevated Pathobiological Determination of Atherosclerosis in Youth Risk Score in Perinatally HIV-Infected Adolescents in South Africa.

Background: Youth living with perinatally acquired HIV infection (YLPHIV) are at risk of developing atherosclerotic cardiovascular disease.

Methods: We determined the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) coronary arteries (CA) and abdominal aorta (AA) risk scores among YLPHIV who are ≥15 years old in Cape Town Adolescent and Antiretroviral Cohort. PDAY score was calculated using non-high-density lipoprotein, high-density lipoprotein cholesterol, hyperglycemia, hypertension, obesity, and smoking; a score ≥1 was considered elevated.

Comparing Cardiovascular Outcomes and Costs of Perindopril-, Enalapril- or Losartan-Based Antihypertensive Regimens in South Africa: Real-World Medical Claims Database Analysis.

Introduction: Differences in class or molecule-specific effects between renin-angiotensin-aldosterone system (RAAS) inhibitors have not been conclusively demonstrated. This study used South African data to assess clinical and cost outcomes of antihypertensive therapy with the three most common RAAS inhibitors: perindopril, losartan and enalapril.

Methods: Using a large, South African private health insurance claims database, we identified patients with a hypertension diagnosis in January 2015 receiving standard doses of perindopril, enalapril or losartan, alone or in combination with other agents.

Myocardial extracellular volume fraction is positively associated with activated monocyte subsets among cART-treated persons living with HIV in South Africa.

Background: Despite treatment with combination antiretroviral therapy (cART), persons living with HIV (PLWH) are at higher risk of cardiac structural abnormalities that may presage clinical heart failure, including myocardial fibrosis. This study assessed whether circulating cellular and soluble protein markers of immune activation cross-sectionally associate with myocardial fibrosis among cART-treated PLWH in South Africa.

Methods: Participants were enrolled in Khayelitsha township near Cape Town, SA.

Infection pre-Ad26.COV2.S-vaccination primes greater class switching and reduced CXCR5 expression by SARS-CoV-2-specific memory B cells.

Neutralizing antibodies strongly correlate with protection for COVID-19 vaccines, but the corresponding memory B cells that form to protect against future infection are relatively understudied. Here we examine the effect of prior SARS-CoV-2 infection on the magnitude and phenotype of the memory B cell response to single dose Johnson and Johnson (Ad26.COV2.

Simulating Subject-Specific Aortic Hemodynamic Effects of Valvular Lesions in Rheumatic Heart Disease.

Rheumatic heart disease (RHD) is a neglected tropical disease despite the substantial global health burden. In this study, we aimed to develop a lower cost method of modeling aortic blood flow using subject-specific velocity profiles, aiding our understanding of RHD's consequences on the structure and function of the ascending aorta. Echocardiography and cardiovascular magnetic resonance (CMR) are often used for diagnosis, including valve dysfunction assessments.

Bringing MRI to low- and middle-income countries: Directions, challenges and potential solutions.

The global disparity of magnetic resonance imaging (MRI) is a major challenge, with many low- and middle-income countries (LMICs) experiencing limited access to MRI. The reasons for limited access are technological, economic and social. With the advancement of MRI technology, we explore why these challenges still prevail, highlighting the importance of MRI as the epidemiology of disease changes in LMICs.

Left ventricular remodeling and its correlates among adolescents with perinatally acquired HIV in South Africa.

Background: Left ventricular (LV) remodeling and its transitions from compensatory adaptations to LV dysfunction have not been examined in adolescents with perinatally acquired HIV infection (PHIV). We used cardiovascular magnetic resonance (CMR) in a cross-sectional study to characterize PHIV-related progressive LV remodeling in adolescents in South Africa.

Methods: Adolescents with PHIV on antiretroviral treatment and their HIV uninfected peers completed 3 T CMR examination.

Distinct T cell functional profiles in SARS-CoV-2 seropositive and seronegative children associated with endemic human coronavirus cross-reactivity.

SARS-CoV-2 infection in children typically results in asymptomatic or mild disease. There is a paucity of studies on antiviral immunity in African children. We investigated SARS-CoV-2-specific T cell responses in 71 unvaccinated asymptomatic South African children who were seropositive or seronegative for SARS-CoV-2.

Homologous Ad26.COV2.S vaccination results in reduced boosting of humoral responses in hybrid immunity, but elicits antibodies of similar magnitude regardless of prior infection.

The impact of previous SARS-CoV-2 infection on the durability of Ad26.COV2.S vaccine-elicited responses, and the effect of homologous boosting has not been well explored.