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- ItemAn 8-year retrospective study of adult and paediatric Burkitt’s lymphoma at Tygerberg Hospital, South Africa(AOSIS, 2020-04-30) Musekwa, Ernest; Chapanduka, Zivanai C.; Bassa, Fatima; Kruger, MarianaBackground: Burkitt lymphoma(BL) is a high grade non-Hodgkin lymphoma, which may be underdiagnosed in South Africa, due to a high burden of infectious diseases such as HIV and TB which may present with similar clinical features. Aim: To describe demographics and clinico-pathological characteristics of patients diagnosed with BL. Setting: Tygerberg Hospital (TBH), South Africa between 2007-2014. Methods: We performed a retrospective descriptive and survival analysis of patients diagnosed with BL at TBH between 01 January 2007 and 31 December 2014 with at least 24-month follow-up. Data was collected from the Tygerberg Lymphoma Study Group database and the South African Children Cancer Study Group Tumour Registry. Results: There were 73 patients with BL, of whom 68 were admitted to TBH and whose data was further analysed. The majority of patients were adults (74%). There was a female predominance in adults and a male predominance in children (p = 0.002). Various regimens were used in adults while a single treatment protocol was used in children. The proportion of patients with HIV and advanced BL was higher in adults than in children. The 2-year overall survival of the treatment group was 45%. The outcome of patients with BL in adults (34%) was poorer than that of children (69%) (p = 0.022). HIV negative patients had a non-significant survival advantage (57%) over HIV positive patients with 41% 2-year overall survival (p = 0.2876). Conclusion: This study demonstrates a better cure rate in children treated for BL compared to adults, with HIV-infection being a risk factor for poor outcome.
- ItemAdenosine deaminase estimations in the differentiation of pleural effusions(Health & Medical Publishing Group, 1982-10) Maritz, F. J.; Malan, C.; Le Roux, I.Adenosine deaminase (ADA) estimations were performed on the pleural fluid from 368 effusions. The mean (±SD) ADA concentration in tuberculous effusions was 92.11 ± 37.05 U/l, and these values were found to be highly statistically different from the 23.3 ± 13.15 U/l in secondary malignant tumours of the pleura, the 34.86 ± 14.2 U/l in mesotheliomas, and the 23.81 ± 15.07 U/l in pulmonary embolism. The ADA values of 64.3 ± 44.95 UlI in lymphoproliferative disorders were less significantly different. No statistical difference could be found between values in the tuberculous group and the ADA levels of 97.57 ± 82 U/l found in para-infective effusions, but these could be distinguished from each other by microscopic examination of the pleural fluid. The importance of ADA estimations in the diagnosis and differentiation of tuberculous effusions is discussed and the role of microscopy is emphasized.
- ItemThe agreement between fasting glucose and markers of chronic glycaemic exposure in individuals with and without chronic kidney disease : a cross-sectional study(BMC (part of Springer Nature), 2020-01-30) George, Cindy; Matsha, Tandi E.; Korf, Marizna; Zemlin, Annalise E.; Erasmus, Rajiv T.; Kengne, Andre P.Background: To assess whether the agreement between fasting glucose and glycated proteins is affected by chronic kidney disease (CKD) in a community-based sample of 1621 mixed-ancestry South Africans. Methods: CKD was defined as an estimated glomerular filtration rate < 60 ml/min/1.73 m2. Fasting plasma glucose and haemoglobin A1c (HbA1c) concentrations were measured by enzymatic hexokinase method and highperformance liquid chromatography, respectively, with fructosamine and glycated albumin measured by immunoturbidimetry and enzymatic method, respectively. Results: Of those with CKD (n = 96), 79, 16 and 5% where in stages 3, 4 and 5, respectively. Those with CKD had higher levels of HbA1c (6.2 vs. 5.7%; p < 0.0001), glycated albumin (15.0 vs. 13.0%; p < 0.0001) and fructosamine levels (269.7 vs. 236.4 μmol/l; p < 0.0001), compared to those without CKD. Higher fasting glucose levels were associated with higher HbA1c, glycated albumin and fructosamine, independent of age, gender, and CKD. However, the association with HbA1c and glycated albumin differed by CKD status, at the upper concentrations of the respective markers (interaction term for both: p ≤ 0.095). Conclusion: Our results suggest that although HbA1c and glycated albumin perform acceptably under conditions of normoglycaemia, these markers correlate less well with blood glucose levels in people with CKD who are not on dialysis.
- ItemAlfal-Fetoproteien in neonatale geelsug(HMPG, 1978-08) Malan Christina; Donald, P. R.; Odendaal , H. J.; Shanley , B. C.The relationship between the concentration of alphal-fetoprotein (AFP) in cord blood and neonatal jaundice has been examined in 259 neonates. Cord blood AFP varies inversely with gestational age, as does the incidence of severe jaundice. Among babies born at term a higher mean AFP concentration in cord blood was found in the group which subsequently developed marked hyperbilirubinaemia. On average, the full-term babies with a cord blood AFP level above 130 mg/l developed more pronounced jaundice than the rest. We conclude that cord blood AFP concentrations reflect the maturity of the liver in both premature and full-term infants. It is a better criterion than the estimation of gestational period by physical examination of the baby.
- ItemApplication of advanced molecular technology in the diagnosis and management of genetic disorders in South Africa(Health & Medical Publishing Group, 2016) Kotze, M. J.Background. Genetic testing has evolved from a niche speciality for diagnosis of rare disorders and carrier screening to subtyping of complex medical conditions for targeted treatment. Genes causing monogenic disorders are well characterised, but risk management of multifactorial and polygenic disorders guided from the genetic background remains a challenge. Objective. This study describes the use of a pathology-supported genetic testing (PSGT) strategy designed to facilitate the move from single- to multi-gene testing and next-generation sequencing (NGS). Methods. In contrast to direct-to-consumer genetic testing, PSGT requires preselection of patients and data integration to determine current and future risk implications. To enable this process, a genomics database resource generated at the interface between the laboratory and clinic is available for clinical interpretation. Results. The PSGT approach led to the development of testing algorithms for improved clinical management of patients with cancer and other complex disorders with a genetic component. Local evidence is presented to demonstrate the application of PSGT for assessment of clinical relevance in patients with rare germline variants and functional polymorphisms underlying shared disease pathways. Conclusion. PSGT is ideally suited to serve as a screening step for microarray analysis and whole genome/exome sequencing as the next frontier in personalised medicine. Use of these advanced molecular technologies to match genotype with phenotype provides a resource for diagnosis and discovery over a lifetime.
- ItemAssessing clustering of metabolic syndrome components available at primary care for Bantu Africans using factor analysis in the general population(BioMed Central, 2013-06) Nasila Sungwacha, John; Tyler, Joanne; Longo-Mbenza, Benjamin; Lasi On'Kin, Jean Bosco Kasiam; Gombet, Thierry; Erasmus, Rajiv T.ABSTRACT: To provide a step-by-step description of the application of factor analysis and interpretation of the results based on anthropometric parameters(body mass index or BMI and waist circumferenceor WC), blood pressure(BP), lipid-lipoprotein(triglycerides and HDL-C) and glucose among Bantu Africans with different numbers and cutoffs of components of metabolic syndrome(MS). This study was a cross-sectional, comparative, and correlational survey conducted between January and April 2005, in Kinshasa Hinterland, DRC. The clustering of cardiovascular risk factors was defined in all, MS group according to IDF(WC, BP, triglycerides, HDL-C, glucose), absence and presence of cardiometabolic risk(CDM) group(BMI,WC, BP, fasting glucose, and post-load glucose). RESULTS:Out of 977 participants, 17.4%( n = 170), 11%( n = 107), and 7.7%(n = 75) had type 2 diabetes mellitus(T2DM), MS, and CDM, respectively. Gender did not influence on all variables. Except BMI, levels of the rest variables were significantly higher in presence of T2DM than non-diabetics. There was a negative correlation between glucose types and BP in absence of CDM. In factor analysis for all, BP(factor 1) and triglycerides-HDL(factor 2) explained 55.4% of the total variance. In factor analysis for MS group, triglycerides-HDL-C(factor 1), BP(factor 2), and abdominal obesity-dysglycemia(factor 3) explained 75.1% of the total variance. In absence of CDM, glucose (factor 1) and obesity(factor 2) explained 48.1% of the total variance. In presence of CDM, 3 factors (factor 1 = glucose, factor 2 = BP, and factor 3 = obesity) explained 73.4% of the total variance. CONCLUSION: The MS pathogenesis may be more glucose-centered than abdominal obesity-centered in not considering lipid-lipoprotein , while BP and triglycerides-HDL-C could be the most strong predictors of MS in the general population. It should be specifically defined by ethnic cut-offs of waist circumference among Bantu Africans.
- ItemAssessment of the association of plant- based diets with cardiovascular disease risk profile in Africa: a systematic review and meta-analysis protocol(BMJ Publishing, 2020-06) Lopes, Tatum; Zemlin, Annalise E.; Erasmus, Rajiv T.; Faber, Mieke; Kengne, Andre P.Introduction Cardiovascular disease (CVD) is currently the leading cause of death worldwide. In Africa where infectious diseases are still the leading cause of death, the contribution of non-communicable diseases led by CVDs has significantly increased in recent years. The rise of CVDs in Africa is attributed at least in part to the adoption of sedentary behaviours and unhealthy eating habits, which are linked with urbanisation and westernisation of cultures. Dietary attributes associated with CVD risk have been less investigated in Africa. However, evidence from developed nations has reported a protective effect of healthy dietary patterns such as plant-based diets (PBDs) on cardiometabolic health. The current protocol is for a review aiming to assess existing evidence on the association of PBDs with CVD risk profile in African populations. Methods and analysis This protocol was developed following the 2015 guidelines of the Preferred Reporting Items for Systematic Review and Meta-analysis Protocols. We will conduct a comprehensive search of the literature for published studies on PBDs in relation to CVD risk profile in African populations. Observational studies published between January 1990 and December 2019 will be screened. A search strategy using keywords and medical subject headings terms will be applied across multiple scientific databases including PubMed-Medline, Scopus and EBSCOhost and the African Journals Online platform. Manual searches of reference lists from relevant articles will be performed. Citations will be traced using the ISI Web of Science to further identify eligible studies. Grey literature will also be screened for relevant abstracts from conference proceedings, and experts in the field will be contacted where appropriate. Two investigators will independently screen all the titles and abstracts to determine which records are eligible for full-text review. Subsequently, two investigators will review the eligible full text using the selection criteria. A third investigator will be consulted to resolve any discrepancies. Data will be extracted from studies that are eligible for the review. Meta-analysis will be performed for studies with similar or comparable methods and reported outcome measures. This will be performed overall, and by major study-level characteristics. Heterogeneity in the estimates across studies will be assessed and quantified with the use of Cochrane Q and I2 statistics, respectively. Publication biases will be investigated through funnel plots and Egger test of bias. Relevant sensitivity analyses will be performed to confirm the robustness of the findings
- ItemC-reactive protein. Properties and biological action with particular reference to systemic lupus erythematosus(Health and Medical Publishing Group (HMPG), 1985) Macfarlane C. M.A dramatic increase in serum C-reactive protein levels occurs in response to specific bacterial infection or tissue damage. This protein forms part of the acute-phase response, and it appears to function as an independent but relatively nonspecific part of the immune response. It has many properties in common with specific IgG. Absence of an adequate C-reactive protein response may play a role in the pathogenesis of systemic lupus erythematosus.
- ItemCase report : an index of suspicion in hyponatraemia(Hrvatsko društvo za medicinsku biokemiju, 2019) Barkhuizen, Marizna; Hoffmann, Mariza; Zöllner, Ekkehard W. A.; Erasmus, Rajiv T.; Zemlin, Annalise E.Serum indices can give valuable information and should be interpreted as a result. Lipaemia can influence results through different mechanisms, an important one being the electrolyte exclusion effect. A case of pseudohyponatraemia due to this is reported. A 15-year-old female with type 2 diabetes was seen for follow-up. Her biochemistry results revealed severe hyponatraemia of 118 mmol/L. Her capillary glucose concentration was 13.7 mmol/L with a corrected sodium of 122 mmol/L. A lipaemic index of 3+ (absolute value 1320) was noted, which was not flagged by the laboratory information system, as it was below the critical lipaemia limit for sodium determination. Repeated analysis of the same sample using a direct ion selective electrode method, the serum sodium concentration was 134 mmol/L (sodium corrected for glucose = 138 mmol/L). A triglyceride concentration was requested, which was severely raised (100.1 mmol/L). The electrolyte exclusion effect is an analytical phenomenon that causes falsely low electrolyte concentrations in the presence of severe lipaemia or hyperproteinaemia when using indirect analytical methods. These methods are used on many modern-day automated chemistry analysers and should be considered in a patient with asymptomatic hyponatraemia.
- ItemA century of trends in adult human height(eLife Sciences Publications, 2016) NCD Risk Factor Collaboration (NCD-RisC)ENGLISH SUMMARY : Being taller is associated with enhanced longevity, and higher education and earnings. We reanalysed 1472 population-based studies, with measurement of height on more than 18.6 million participants to estimate mean height for people born between 1896 and 1996 in 200 countries. The largest gain in adult height over the past century has occurred in South Korean women and Iranian men, who became 20.2 cm (95% credible interval 17.5–22.7) and 16.5 cm (13.3–19.7) taller, respectively. In contrast, there was little change in adult height in some sub-Saharan African countries and in South Asia over the century of analysis. The tallest people over these 100 years are men born in the Netherlands in the last quarter of 20th century, whose average heights surpassed 182.5 cm, and the shortest were women born in Guatemala in 1896 (140.3 cm; 135.8–144.8). The height differential between the tallest and shortest populations was 19-20 cm a century ago, and has remained the same for women and increased for men a century later despite substantial changes in the ranking of countries.
- ItemChronic kidney disease in sub-Saharan Africa(Elsevier, 2019) Matsha, Tandi E.; Erasmus, Rajiv T.No abstract available.
- ItemChronic kidney diseases in mixed ancestry South African populations : prevalence, determinants and concordance between kidney function estimators(BioMed Central, 2013-04) Matsha, Tandi E.; Yako, Yandiswa Y.; Rensburg, Megan A.; Hassan, Mogamat S.; Kengne, Andre P.; Erasmus, Rajiv T.ABSTRACT: Population-based data on the burden of chronic kidney disease (CKD) in sub-Saharan Africa is still very limited. We assessed the prevalence and determinants of CKD, and evaluated the concordance of commonly advocated estimators of glomerular filtration rate (eGFR) in a mixed ancestry population from South Africa. Methods Participants were a population-based sample of adults selected from the Bellville-South community in the metropolitan city of Cape Town. eGFR was based on the Cockroft-Gault (CG), Modification of Diet in Kidney Disease (MDRD) and CKD Epidemiology Collaboration (CKD-EPI) equations (with and without adjustment for ethnicity). Kidney function staging used the Kidney Disease Outcome Quality Initiative (KDOQI) classification. Logistic regressions and kappa statistic were used to investigate determinants of CKD and assess the agreement between different estimators. Results The crude prevalence of CKD stage 3–5 was 14.8% for Cockcroft-Gault, 7.6% and 23.9% respectively for the MDRD with and without ethnicity correction, and 7.4% and 17.3% for the CKD-EPI equations with and without ethnicity correction. The highest agreement between GFR estimators was between MDRD and CKD-EPI equations, both with ethnicity correction, Kappa 0.91 (95% CI: 0.86-0.95), correlation coefficient 0.95 (95% CI: 0.94-0.96). In multivariable logistic regression models, sex, age and known hypertension were consistently associated with CKD stage 3–5 across the 5 estimators. Conclusions The prevalence of CKD stages greater than 3 is the highest reported in Africa. This study provides evidence for support of the CKD-EPI equation for eGFR reporting and CKD classification.
- ItemChronic kidney diseases in mixed ancestry South African populations : prevalence, determinants and concordance between kidney function estimators(BioMed Central, 2013-04) Matsha, Tandi E.; Yako, Yandiswa Y.; Van Rensburg, Megan; Hassan, Mogamat S.; Kengne, Andre P.; Erasmus, Rajiv T.Background: Population-based data on the burden of chronic kidney disease (CKD) in sub-Saharan Africa is still very limited. We assessed the prevalence and determinants of CKD, and evaluated the concordance of commonly advocated estimators of glomerular filtration rate (eGFR) in a mixed ancestry population from South Africa. Methods: Participants were a population-based sample of adults selected from the Bellville-South community in the metropolitan city of Cape Town. eGFR was based on the Cockroft-Gault (CG), Modification of Diet in Kidney Disease (MDRD) and CKD Epidemiology Collaboration (CKD-EPI) equations (with and without adjustment for ethnicity). Kidney function staging used the Kidney Disease Outcome Quality Initiative (KDOQI) classification. Logistic regressions and kappa statistic were used to investigate determinants of CKD and assess the agreement between different estimators. Results: The crude prevalence of CKD stage 3–5 was 14.8% for Cockcroft-Gault, 7.6% and 23.9% respectively for the MDRD with and without ethnicity correction, and 7.4% and 17.3% for the CKD-EPI equations with and without ethnicity correction. The highest agreement between GFR estimators was between MDRD and CKD-EPI equations, both with ethnicity correction, Kappa 0.91 (95% CI: 0.86-0.95), correlation coefficient 0.95 (95% CI: 0.94-0.96). In multivariable logistic regression models, sex, age and known hypertension were consistently associated with CKD stage 3–5 across the 5 estimators Conclusions: The prevalence of CKD stages greater than 3 is the highest reported in Africa. This study provides evidence for support of the CKD-EPI equation for eGFR reporting and CKD classification.
- ItemCirculating miR-30a-5p and miR-182-5p in prediabetes and screen-detected diabetes mellitus(Dove Press, 2020-12) Weale, Cecil Jack; Matshazi, Don M.; Davids, Saarah F. G.; Raghubeer, Shanel; Erasmus, Rajiv T.; Kengne, Andre Pascal; Davison, Glenda Mary; Matsha, Tandi E.Background: microRNAs (miRNAs) have been touted as potential diagnostic and prognostic biomarkers for various diseases. The aim of the present study was to evaluate the diagnostic value of miR-30a-5p and miR-182-5p for prediabetes and screen-detected type 2 diabetes mellitus (T2DM). Methods: The study included 1270 participants (207 prediabetes, 94 screen-detected diabetes and 969 normotolerant) from the Vascular and Metabolic Health (VMH) study. Whole blood levels of miR-30a-5p and miR-182-5p were quantitated by RT-qPCR. Multivariable logistic regressions were used to relate miRNAs with prediabetes or T2DM and receiver operating characteristic (ROC) curves were used to evaluate the ability of each miRNA to diagnose these conditions. Results: Both miRNAs were significantly highly expressed in individuals with prediabetes or T2DM (both ≥3.2-fold, and p<0.001). We also observed significant under-expression in T2DM relative to prediabetes for miR-182-5p (0.49-fold, p=0.001). Age, sex and BMI-adjusted partial correlation coefficient analysis revealed a significant correlation between the two miRNAs across glucose tolerance statuses (r≥0.932, p<0.001). In normotolerant individuals, both miRNAs showed a negative correlation with waist circumference and positive correlation with HDL-cholesterol whilst in T2DM they correlated positively with hip circumference, 2-hour insulin, HDL- and LDL-cholesterol. Multivariable logistic regressions revealed both miRNAs to be consistently and continuously associated with prediabetes or T2DM (OR≥1.18, 95% 95% CI: 1.10-1.28, p<0.001), while only miR-182-5p associated with a reduced prevalence of T2DM relative to prediabetes (OR: 0.89, 95% CI: 0.83-0.96, p=0.003). In ROC analyses, miR-182-5p almost outperformed HbA1c in diagnosing prediabetes; area under the curve 0.74 vs 0.69. Conclusion: Our findings demonstrate that miR-30a-5p and miR-182-5p are associated with dysglycaemia and could potentially predict prediabetes, particularly miR-182-5p.
- ItemComparison of equations for estimating glomerular filtration rate in screening for chronic kidney disease in asymptomatic black Africans : a cross sectional study(BioMed Central, 2017-12-20) Omuse, Geoffrey; Maina, Daniel; Mwangi, Jane; Wambua, Caroline; Kanyua, Alice; Kagotho, Elizabeth; Amayo, Angela; Ojwang, Peter; Erasmus, RajivBackground: Several equations have been developed to estimate glomerular filtration rate (eGFR). The common equations used were derived from populations predominantly comprised of Caucasians with chronic kidney disease (CKD). Some of the equations provide a correction factor for African-Americans due to their relatively increased muscle mass and this has been extrapolated to black Africans. Studies carried out in Africa in patients with CKD suggest that using this correction factor for the black African race may not be appropriate. However, these studies were not carried out in healthy individuals and as such the extrapolation of the findings to an asymptomatic black African population is questionable. We sought to compare the proportion of asymptomatic black Africans reported as having reduced eGFR using various eGFR equations. We further compared the association between known risk factors for CKD with eGFR determined using the different equations. Methods: We used participant and laboratory data collected as part of a global reference interval study conducted by the Committee of Reference Intervals and Decision Limits (C-RIDL) under the International Federation of Clinical Chemistry (IFCC). Serum creatinine values were used to calculate eGFR using the Cockcroft-Gault (CG), re-expressed 4 variable modified diet in renal disease (4v–MDRD), full age spectrum (FAS) and chronic kidney disease epidemiology collaboration equations (CKD-EPI). CKD classification based on eGFR was determined for every participant. Results: A total of 533 participants were included comprising 273 (51.2%) females. The 4v–MDRD equation without correction for race classified the least number of participants (61.7%) as having an eGFR equivalent to CKD stage G1 compared to 93.6% for CKD-EPI with correction for race. Only age had a statistically significant linear association with eGFR across all equations after performing multiple regression analysis. The multiple correlation coefficients for CKD risk factors were higher for CKD-EPI determined eGFRs. Conclusions: This study found that eGFR determined using CKD-EPI equations better correlated with a prediction model that included risk factors for CKD and classified fewer asymptomatic black Africans as having a reduced eGFR compared to 4v–MDRD, FAS and CG corrected for body surface area.
- ItemThe conundrum of iron in multiple sclerosis – time for an individualised approach(Springer US, 2012-03) Janse Van Rensburg, Susan; Kotze, Maritha J.; Van Toorn, RonaldAlthough the involvement of immune mechanisms in multiple sclerosis (MS) is undisputed, some argue that there is insufficient evidence to support the hypothesis that MS is an autoimmune disease, and that the difference between immune- and autoimmune disease mechanisms has yet to be clearly delineated. Uncertainties surrounding MS disease pathogenesis and the modest efficacy of currently used disease modifying treatments (DMTs) in the prevention of disability, warrant the need to explore other possibilities. It is evident from the literature that people diagnosed with MS differ widely in symptoms and clinical outcome - some patients have a benign disease course over many years without requiring any DMTs. Attempting to include all patients into a single entity is an oversimplification and may obscure important observations with therapeutic consequences. In this review we advocate an individualised approach named Pathology Supported Genetic Testing (PSGT), in which genetic tests are combined with biochemical measurements in order to identify subgroups of patients requiring different treatments. Iron dysregulation in MS is used as an example of how this approach may benefit patients. The theory that iron deposition in the brain contributes to MS pathogenesis has caused uncertainty among patients as to whether they should avoid iron. However, the fact that a subgroup of people diagnosed with MS show clinical improvement when they are on iron supplementation emphasises the importance of individualised therapy, based on genetic and biochemical determinations.
- ItemCoronavirus disease 2019 (COVID-19) and the reninangiotensin system : a closer look at angiotensin-converting enzyme 2 (ACE2)(Sage, 2020-05-01) Zemlin, Annalise E.; Wiese, OwenENGLISH ABSTRACT: Since the first cases of atypical pneumonia linked to the Huanan Seafood Wholesale Market in Wuhan, China were described in late December 2019, the global landscape has changed radically. In March 2020, the World Health Organization (WHO) declared COVID-19 a global pandemic, and at the time of writing this review just over 3 million individuals have been infected with more than 200 000 deaths globally. Numerous countries are in “lockdown”, social distancing is the new norm, even the most advanced healthcare systems are under pressure, and a global economic recession seems inevitable. A novel coronavirus (SARS-CoV-2) was identified as the aetiological agent. From experience with previous coronavirus epidemics, namely the Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) in 2004 and 2012 respectively, it was postulated that the angiotensin-converting enzyme-2 (ACE2) receptor is a possible port of cell entry. ACE2 is part of the renin-angiotensin system (RAS), and is also associated with lung and cardiovascular disorders and inflammation. Recent studies have confirmed that ACE2 is the port of entry for SARS-CoV-2. Male sex, advanced age, and a number of associated comorbidities have been identified as risk factors for infection with COVID-19. Many high-risk COVID-19 patients with comorbidities are on ACE inhibitors and angiotensin receptor blockers, and this has sparked debate about whether to continue these treatment regimes. Attention has also shifted to ACE2 being a target for future therapies or vaccines against COVID-19. In this review, we discuss COVID-19 and its complex relationship with ACE2.
- ItemDifferential prevalence and associations of overweight and obesity by gender and population group among school learners in South Africa : a cross-sectional study(BioMed Central, 2017-07-17) Negash, Sarah; Agyemang, Charles; Matsha, Tandi E.; Peer, Nasheeta; Erasmus, Rajiv T.; Kengne, Andre P.Background: Factors influencing the increasing prevalence of overweight/obesity among children and adolescents in sub-Saharan Africa remain unclear. We assessed the prevalence and determinants of overweight and obesity and effects on cardio-metabolic profile in school learners in the Western Cape, South Africa. Methods: Cross-sectional data were collected from 7 to 18-year-old South African school learners attending 14 schools, randomly selected from 107 government schools in the areas. The learners were selected through stratified random sampling techniques. Logistic regressions were used to assess the determinants of overweight/obesity and its association with cardio-metabolic profile. Results: Among the 1559 participants, the overall prevalence of overweight/obesity was 22.9%. Being a girl (Odds ratio 2.51, 95% CI: 1.92–3.29), or Black African (1.35, 1.04–.75) was associated with increased odds of being overweight/obese. The identified health consequences among the overweight/obese learners differed between the ethnic groups. Overweight/obese coloured (mixed ancestry) learners were more likely to have hypertension (3.27, 1.18–9.08), hypertriglyceridemia (1.94, 0.99–3.78) and low high-density lipoprotein cholesterol (HDL-C) (3.65, 2.33–5.72), overweight/obese Black African learners had higher odds for hypertension (3.62, 1.31–10.04) and low HDL-C (1.56, 1.01–2.40) and overweight/obese White learners were prone to low HDL-C (5.04, 1.35–18.80). Conclusions: Overweight/obesity is highly prevalent among school learners in Western Cape (South Africa), with being female or Black African increasing the odds. That overweight/obesity is also associated with adverse cardio-metabolic risk profile aggravates the problem and suggests worse cardiovascular outcomes in South African young adults in the future.
- ItemThe discriminatory power of visceral adipose tissue area vs anthropometric measures as a diagnostic marker for metabolic syndrome in South African women(BMC (part of Springer Nature), 2019-11-08) Davidson, Florence E.; Matsha, Tandi E.; Erasmus, Rajiv T.; Kengne, Andre P.; Goedecke, Julia H.Background: A number of studies have shown central adiposity, in particular visceral adipose tissue (VAT) accumulation to be a hallmark of metabolic syndrome (MetS). In clinical practice, waist circumference (WC) is used as a proxy for VAT. Aim: To compare the ability of dual energy x-ray absorptiometry (DXA)-derived VAT area and anthropometric measures of adiposity for diagnosing MetS in a sample of high risk South African women. Methods: MetS was quantified using the Joint Interim Statement (JIS) criteria. Fasting glucose, insulin and lipid profile were measured in 204 post-menopausal women. Anthropometry measures included body mass index (BMI), WC, waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and a body shape index (ABSI). The area under the curve (AUC) was used to assess their performance in detecting any two components of MetS (excluding WC). Optimal WC and VAT area cut-points were derived to compare their performance for diagnosing MetS and to compare to internationally recognised cut-points. Results: The highest AUC for the prediction of MetS was recorded for VAT, followed by WHtR and WC (AUC, 0.767, 0.747 and 0.738 respectively), but these did not differ significantly (all p ≥ 0.192). In contrast, VAT was significantly better than BMI (p = 0.028), hip (p = 0.0004) and ABSI (p < 0.0001). The optimal WC (94.4 cm) and VAT area (174 cm2 based on the Youden’s index method and 175.50 cm2 based on the CTL approach) cut-points performed similarly in detecting MetS. Conclusion: DXA-derived VAT and WC had the same overall performance in discriminating the presence of any 2 MetS components in high risk South African women. These findings support the current recommendations of using WC rather than VAT for MetS risk screening, as it is cheap, accessible and easy to measure.
- ItemDistribution and association of hs-CRP with cardiovascular risk variables of metabolic syndrome in adolescent learners(AOSIS Publishing, 2012-06) Rensburg, Megan A.; Matsha, Tandi; Hoffman, Mariza; Hassan, Mogamat S.; Erasmus, Rajiv T.Objective: Metabolic syndrome (MetS) and its associated cardiovascular risk are on the increase in children. High-sensitivity C-reactive protein (hs-CRP) has emerged as a useful marker for inflammation associated with atherosclerosis and cardiovascular disease. Our aim was to determine the distribution of hs-CRP in an effort to identify the MetS variable that is critical in modulating plasma CRP levels in a population of South African adolescents. Design: A cross-sectional analytical study design was used for this investigation, where the dependent and independent variables were measured simultaneously. Methods: Anthropometric variables, blood pressure, fasting blood glucose and lipids were performed on 324 consenting learners aged 15–18 years from three different ethnic groups (Black, White and Coloured). The National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) for ages 15–18 year olds was used to define MetS. Results: The prevalence of MetS and obesity was 3.7% and 7.1%, respectively. The hs-CRP levels were significantly higher in subjects with a waist-circumference greater than the 90th percentile (p < 0.01) and in obese learners with MetS, but was lower in adolescents with normal weight and MetS. Median hs-CRP levels increased with an increasing number of metabolic abnormalities and exceeded 3 mg/L in 19% of adolescents. Gender and ethnic differences were observed. Conclusion: Our findings suggest that obesity and waist circumference appear to be major mediators of hs-CRP levels in South African adolescents.