Screening for diabetes mellitus in learners residing in the Belhar, Delft and Mfuleni communities of Cape Town, Western Cape, South Africa

Background Historically, children and adolescents have been diagnosed with type 1 diabetes mellitus and it was thought that type 2 diabetes mellitus occurred only in adults. There are increasing reports of type 2 diabetes in children globally, with some as young as eight years old being affected. The average age of diagnosis in this group was 13 years. This has been attributed to the “epidemic” of overweight and obesity currently being observed in both developed and developing countries. There is a paucity of data on the incidence and prevalence of type 2 diabetes mellitus in children compared with that for adults. Most studies reported to date have been clinic based. The few population-based studies that were carried out between 1965 and 1995 have shown a several-fold increase in the incidence rates of type 2 diabetes mellitus. The prevalence of diabetes mellitus in South Africa has risen dramatically in the past two decades, with the highest prevalence rates being found in the adult population of Indian origin, followed by the African, Coloured (mixed ancestry) and White population groups.Objectives This study was undertaken to screen 10 to 16-year-old learners residing in three urban areas of Cape Town, South Africa for diabetes mellitus.Methods Fasting and casual blood glucose levels were measured using a commercial glucometer in 338 randomly selected schoolchildren aged from 10 to 16 from the urban communities of Belhar, Delft and Mfuleni in Cape Town. Early morning urine samples were also tested for the presence of glucose using dipsticks. Anthropometric measurements were carried out using standard procedures. A structured questionnaire on physical activity, demographics and diabetic status was administered to all participants. Overweight and obesity were estimated according to The International Obesity Task Force (IOTF) criteria.Results A total of 15.7% of the learners were overweight and 6.2% were obese; 11.5% of the learners had a first-degree relative with diabetes and 29.9% had a second-degree relative with diabetes. Mean fasting and casual glucose values of 4.26 ± 0.63 mmol/l and 4.58 ± 0.79 mmol/l (pConclusionThese results suggest that population screening of children may not be viable, despite the increase in the prevalence of diabetes mellitus amongst various racial groups in South Africa.For full text, click here: SA Fam Pract 2006;48(6):16-16

Potential for medical error: Incorrectly completed request forms for thyroid function tests limit pathologists’ advice to clinicians

Background. Various publications have highlighted the significance of laboratory errors in the pre- and post-analytical phases and their impact on results. Thyroid-stimulating hormone (TSH) is a first-line thyroid function test and, if abnormal, reflex thyroxine (T4) or tri-iodothyronine (T3) testing is requested, depending on clinical and medication data provided. Interpretative comments are added to all TFTresults.Objectives. In view of the paucity of articles describing such errors, we audited laboratory request forms requesting thyroid function tests (TFT), received from primary care clinics and regional hospitals at our laboratory.Design. We assessed 482 laboratory request forms for TFT from primary health care clinics for specific parameters. Results. A total of 482 forms were analysed. Medication/s used by the patient (74.5%) and doctor’s contact number (65.1%) were the most commonly incomplete parameters. Of the 123 patients with medication details, 62 (50.4%) were on thyroxine.Conclusions. There are few studies examining the frequencyand impact of incomplete laboratory forms on laboratory errors, and even fewer studies examining interpretative comments accompanying clinical biochemistry results. We studied how pre-analytical errors in completing request forms may lead to incorrect interpretative comments and inappropriate reflex testing, and so influence the quality of the post-analytical phase

High prevalence of diabetes mellitus and metabolic syndrome in a South African coloured population: Baseline data of a study in Bellville, Cape Town

Objective. The coloured population has the second-highest prevalence of diabetes in South Africa. However, the data were based on a study conducted almost 20 years ago in a peri-urban coloured population of the Western Cape. We aimed to determine the prevalence of diabetes mellitus and metabolic syndrome in an urban coloured population in South Africa.Design. In a cross-sectional survey, 642 participants aged .31 years were drawn from an urban community of Bellville South, Cape Town, from mid-January 2008 to March 2009. Type 2 diabetes was assessed according to the WHO criteria, and metabolic syndrome was based on the International Diabetes Federation (IDF), ATP III and 2009 Joint Interim Statement (JIS) definition.Results. The crude prevalence of 28.2% (age-adjusted 26.3%, 95% confidence interval (CI) 22.0 - 30.3) for type 2 diabetes was: 4.4% (age-adjusted 3.2%, 95% CI 1.6 - 4.9) for impaired fasting glycaemia, and 15.3% (age-adjusted 15.0%, 95% CI 11.4 - 18.6) for impaired glucose tolerance. Undiagnosed type 2 diabetes was present in 18.1% (age-adjusted 16.8%, 95% CI 13.3 - 20.4). The crude prevalence of metabolic syndrome was higher with the JIS definition (62.0%) than the IDF (60.6%), and the National Cholesterol Education Program (NCEP) ATP III (55.4%). There was good overall agreement between the MetS criteria, k=0.89 (95% CI 0.85 - 0.92).Conclusion. The prevalence of diabetes has increased hugely in the coloured community, and the high prevalence of undiagnosed diabetes portends that cardiovascular diseases might grow to epidemic proportions in the near future in South Africa

Association of the ENPP1 rs997509 polymorphism with obesity in South African mixed ancestry learners

Background: The Ectonucleotide Pyrophosphatase Phosphodiesterase1 (ENPP1) polymorphisms have been associated with metabolic traits. There is no data on the effect of ENPP1 in South African children or adults. Objective: To investigate the role of K121Q (rs1044498), rs997509 and rs9402349 in obesity and other components of the metabolic syndrome. Design: A case-control study. Subjects: Sixty four obese and 64 lean mixed ancestry learners. Setting: Western Cape, South Africa. Main outcome measure: The EN PP1 rs997509T allele is independently associated with obesity in children of mixed ancestry from South Africa. Results: The T allele frequency of the rs997509 differed significantly between obese and controls, p=0.0100 and increased the risk of being obese, p = 0.0238. Furthermore, the estimated effect of the T allele was an increase of 8.6 cm in waist circumference, 10.2 kg in weight and a corresponding 4.9 kg/m2 in BMI. Individuals carrying both the 121Q and the T allele of rs997509 were more associated with obesity (odds ratio = 3.85, 95% CI: 1.13 to 13.09) whilst those carrying the C allele of rs997509 in the presence of 121Q were likely to be lean with odds ratio of obesity 0.41 (95% CI: 0.19 to 0.87). Conclusion: Our findings suggest that ENPP1 polymorphisms may contribute to different metabolic characteristics, all of which are associated with insulin resistance in mixed ancestry children of South Africa. However, a larger study is required to confirm findings of this study.East African Medical Journal Vol. 87 No. 8 August 201

Latent class analysis: an innovative approach for identification of clinical and laboratory markers of disease severity among COVID-19 patients admitted to the intensive care unit

Objective: The aim of this study was to identify clinical and laboratory phenotype distribution patterns and their usefulness as prognostic markers in COVID-19 patients admitted to the intensive care unit (ICU) at Tygerberg Hospital, Cape Town. Methods and results: A latent class analysis (LCA) model was applied in a prospective, observational cohort study. Data from 343 COVID-19 patients were analysed. Two distinct phenotypes (1 and 2) were identified, comprising 68.46% and 31.54% of patients, respectively. The phenotype 2 patients were characterized by increased coagulopathy markers (D-dimer, median value 1.73 ng/L vs 0.94 ng/L; p < 0.001), end-organ dysfunction (creatinine, median value 79 µmol/L vs 69.5 µmol/L; p < 0.003), under-perfusion markers (lactate, median value 1.60 mmol/L vs 1.20 mmol/L; p < 0.001), abnormal cardiac function markers (median N‐terminal pro‐brain natriuretic peptide (NT-proBNP) 314 pg/ml vs 63.5 pg/ml; p < 0.001 and median high‐sensitivity cardiac troponin (Hs-TropT) 39 ng/L vs 12 ng/L; p < 0.001), and acute inflammatory syndrome (median neutrophil-to-lymphocyte ratio 15.08 vs 8.68; p < 0.001 and median monocyte value 0.68 × 109/L vs 0.45 × 109/L; p < 0.001). Conclusion: The identification of COVID-19 phenotypes and sub-phenotypes in ICU patients could help as a prognostic marker in the day-to-day management of COVID-19 patients admitted to the ICU

Worldwide trends in diabetes since 1980: a pooled analysis of 751 population-based studies with 4.4 million participants

BACKGROUND: One of the global targets for non-communicable diseases is to halt, by 2025, the rise in the age-standardised adult prevalence of diabetes at its 2010 levels. We aimed to estimate worldwide trends in diabetes, how likely it is for countries to achieve the global target, and how changes in prevalence, together with population growth and ageing, are affecting the number of adults with diabetes. METHODS: We pooled data from population-based studies that had collected data on diabetes through measurement of its biomarkers. We used a Bayesian hierarchical model to estimate trends in diabetes prevalence—defined as fasting plasma glucose of 7·0 mmol/L or higher, or history of diagnosis with diabetes, or use of insulin or oral hypoglycaemic drugs—in 200 countries and territories in 21 regions, by sex and from 1980 to 2014. We also calculated the posterior probability of meeting the global diabetes target if post-2000 trends continue. FINDINGS: We used data from 751 studies including 4 372 000 adults from 146 of the 200 countries we make estimates for. Global age-standardised diabetes prevalence increased from 4·3% (95% credible interval 2·4–7·0) in 1980 to 9·0% (7·2–11·1) in 2014 in men, and from 5·0% (2·9–7·9) to 7·9% (6·4–9·7) in women. The number of adults with diabetes in the world increased from 108 million in 1980 to 422 million in 2014 (28·5% due to the rise in prevalence, 39·7% due to population growth and ageing, and 31·8% due to interaction of these two factors). Age-standardised adult diabetes prevalence in 2014 was lowest in northwestern Europe, and highest in Polynesia and Micronesia, at nearly 25%, followed by Melanesia and the Middle East and north Africa. Between 1980 and 2014 there was little change in age-standardised diabetes prevalence in adult women in continental western Europe, although crude prevalence rose because of ageing of the population. By contrast, age-standardised adult prevalence rose by 15 percentage points in men and women in Polynesia and Micronesia. In 2014, American Samoa had the highest national prevalence of diabetes (>30% in both sexes), with age-standardised adult prevalence also higher than 25% in some other islands in Polynesia and Micronesia. If post-2000 trends continue, the probability of meeting the global target of halting the rise in the prevalence of diabetes by 2025 at the 2010 level worldwide is lower than 1% for men and is 1% for women. Only nine countries for men and 29 countries for women, mostly in western Europe, have a 50% or higher probability of meeting the global target. INTERPRETATION: Since 1980, age-standardised diabetes prevalence in adults has increased, or at best remained unchanged, in every country. Together with population growth and ageing, this rise has led to a near quadrupling of the number of adults with diabetes worldwide. The burden of diabetes, both in terms of prevalence and number of adults affected, has increased faster in low-income and middle-income countries than in high-income countries. FUNDING: Wellcome Trust

Comparison of patients with severe COVID-19 admitted to an intensive care unit in South Africa during the first and second wave of the COVID-19 pandemic

BACKGROUND: The second wave of coronavirus disease 2019 (COVID‑19), dominated by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Beta variant, has been reported to be associated with increased severity in South Africa (SA). OBJECTIVES: To describe and compare clinical characteristics, management and outcomes of COVID‑19 patients admitted to an intensive care unit (ICU) in SA during the first and second waves. METHODS: In a prospective, single-centre, descriptive study, we compared all patients with severe COVID‑19 admitted to ICU during the first and second waves. The primary outcomes assessed were ICU mortality and ICU length of stay (LOS). RESULTS: In 490 patients with comparable ages and comorbidities, no difference in mortality was demonstrated during the second compared with the first wave (65.9% v. 62.5%, p=0.57). ICU LOS was longer in the second wave (10 v. 6 days, p<0.001). More female admissions (67.1% v. 44.6%, p<0.001) and a greater proportion of patients were managed with invasive mechanical ventilation than with non-invasive respiratory support (39.0% v. 14%, p<0.001) in the second wave. CONCLUSIONS: While clinical characteristics were comparable between the two waves, a higher proportion of patients was invasively ventilated and ICU stay was longer in the second. ICU mortality was unchanged

Immunologic and vascular biomarkers of mortality in critical COVID-19 in a South African cohort

Introduction: Biomarkers predicting mortality among critical Coronavirus disease 2019 (COVID-19) patients provide insight into the underlying pathophysiology of fatal disease and assist with triaging of cases in overburdened settings. However, data describing these biomarkers in Sub-Saharan African populations are sparse. Methods: We collected serum samples and corresponding clinical data from 87 patients with critical COVID-19 on day 1 of admission to the intensive care unit (ICU) of a tertiary hospital in Cape Town, South Africa, during the second wave of the COVID-19 pandemic. A second sample from the same patients was collected on day 7 of ICU admission. Patients were followed up until in-hospital death or hospital discharge. A custom-designed 52 biomarker panel was performed on the Luminex® platform. Data were analyzed for any association between biomarkers and mortality based on pre-determined functional groups, and individual analytes. Results: Of 87 patients, 55 (63.2%) died and 32 (36.8%) survived. We found a dysregulated cytokine response in patients who died, with elevated levels of type-1 and type-2 cytokines, chemokines, and acute phase reactants, as well as reduced levels of regulatory T cell cytokines. Interleukin (IL)-15 and IL-18 were elevated in those who died, and levels reduced over time in those who survived. Procalcitonin (PCT), C-reactive protein, Endothelin-1 and vascular cell adhesion molecule-1 were elevated in those who died. Discussion: These results show the pattern of dysregulation in critical COVID-19 in a Sub-Saharan African cohort. They suggest that fatal COVID-19 involved excessive activation of cytotoxic cells and the NLRP3 (nucleotide-binding domain, leucine-rich–containing family, pyrin domain–containing-3) inflammasome. Furthermore, superinfection and endothelial dysfunction with thrombosis might have contributed to mortality. HIV infection did not affect the outcome. A clinically relevant biosignature including PCT, pH and lymphocyte percentage on differential count, had an 84.8% sensitivity for mortality, and outperformed the Luminex-derived biosignature

Prognostic value of biochemical parameters among severe COVID-19 patients admitted to an intensive care unit of a tertiary hospital in South Africa

Background: Data on biochemical markers and their association with mortality rates in patients with severe coronavirus disease 2019 (COVID-19) admitted to intensive care units (ICUs) in sub-Saharan Africa are scarce. An evaluation of baseline routine biochemical parameters was performed in COVID-19 patients admitted to the ICU, in order to identify prognostic biomarkers. Methods: Demographic, clinical, and laboratory data were collected prospectively from patients with PCR-confirmed COVID-19 admitted to the adult ICU of a tertiary hospital in Cape Town, South Africa, between October 2020 and February 2021. Robust Poisson regression methods and the receiver operating characteristic (ROC) curve were used to explore the association of biochemical parameters with severity and mortality. Results: A total of 82 patients (median age 53.8 years, interquartile range 46.4–59.7 years) were enrolled, of whom 55 (67%) were female and 27 (33%) were male. The median duration of ICU stay was 10 days (interquartile range 5–14 days); 54/82 patients died (66% case fatality rate). Baseline lactate dehydrogenase (LDH) (adjusted relative risk 1.002, 95% confidence interval 1.0004–1.004; P = 0.016) and N-terminal pro B-type natriuretic peptide (NT-proBNP) (adjusted relative risk 1.0004, 95% confidence interval 1.0001–1.0007; P = 0.014) were both found to be independent risk factors of a poor prognosis, with optimal cut-off values of 449.5 U/l (sensitivity 100%, specificity 43%) and 551 pg/ml (sensitivity 49%, specificity 86%), respectively. Conclusions: LDH and NT-proBNP appear to be promising predictors of a poor prognosis in COVID-19 patients in the ICU. Studies with a larger sample size are required to confirm the validity of this combination of biomarkers