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Papers by Paul Rheeder

Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy, 2021

Purpose: Gestational diabetes mellitus (GDM) is a growing public health concern. GDM affects appr... more Purpose: Gestational diabetes mellitus (GDM) is a growing public health concern. GDM affects approximately 14% of pregnancies globally, and without effective treatment, is associated with short-and long-term complications in mother and child. Lower serum adiponectin (ADIPOQ) concentrations and aberrant DNA methylation have been reported during GDM. The aim of this study was to investigate the association between the ADIPOQ −11377C>G and −11391G>A, and methylenetetrahydrofolate reductase (MTHFR) 677C>T polymorphisms and GDM in a population of black South African women. Materials and Methods: DNA was isolated from the peripheral blood of 447 pregnant women with (n=116) or without (n=331) GDM, where after ADIPOQ (rs266729 and rs17300539) and MTHFR (rs1801133) polymorphisms were genotyped using TaqMan Quantitative Real-Time PCR analysis. Results: Women with GDM had a higher body mass index (p=0.012), were more insulin resistant (p<0.001) and had lower adiponectin levels (p=0.013) compared to pregnant women with normoglycemia. Genotypic, dominant and recessive genetic models showed no association between ADIPOQ rs266729 and rs17300539 and MTHFR rs1801133 polymorphisms and GDM. Intriguingly, the risk G allele of ADIPOQ rs266729 was associated with higher fasting glucose and insulin concentrations, while the T allele in MTHFR rs1801133 was associated with higher fasting insulin concentrations only. Conclusion: ADIPOQ rs266729 and rs17300539 and MTHFR rs1801133 polymorphisms are not associated with GDM in a population of black South African women. These findings suggest that these single nucleotide polymorphisms (SNPs) do not individually increase GDM risk in the African population. However, the role of these SNPs in possible genegene or gene-environment interactions remain to be established.

International Journal of Molecular Sciences

Increasing evidence implicate altered DNA methylation in the pathophysiology of gestational diabe... more Increasing evidence implicate altered DNA methylation in the pathophysiology of gestational diabetes mellitus (GDM). This exploratory study probed the association between GDM and peripheral blood DNA methylation patterns in South African women. Genome-wide DNA methylation profiling was conducted in women with (n = 12) or without (n = 12) GDM using the Illumina Infinium HumanMethylationEPIC BeadChip array. Functional analysis of differentially methylated genes was conducted using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. A total of 1046 CpG sites (associated with 939 genes) were differentially methylated between GDM and non-GDM groups. Enriched pathways included GDM-related pathways such as insulin resistance, glucose metabolism and inflammation. DNA methylation of the top five CpG loci showed distinct methylation patterns in GDM and non-GDM groups and was correlated with glucose concentrations. Of these, one CpG site mapped to the calmod...

African Journal of Primary Health Care & Family Medicine

Background: Middle and lower income countries are challenged with a double burden of disease: whi... more Background: Middle and lower income countries are challenged with a double burden of disease: while still coping with the onslaught of Human Immunodeficiency Virus (HIV) and increasing levels of tuberculosis (TB), there is a considerable increase in the level of noncommunicable diseases (NCDs). The poor are especially disadvantaged and are at an increased risk for NCDs. Adequate healthcare resources for this environment can only be allocated once the extent and exact nature of the problem is determined.Aim and setting: The aim of this study was to collect demographic and NCD-related data in the poorest community of the poorest province of South Africa in order to determine the extent of the problem and advise on allocation of resources accordingly.Methods: Data were collected via a household primary health screening process, which included taking anthropometric measurements, blood pressure and blood glucose and referring to clinics for further testing and treatment where necessary.R...

International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics, 2018

To investigate the performance of the Roche Accuchek Active glucometer in diagnosing gestational ... more To investigate the performance of the Roche Accuchek Active glucometer in diagnosing gestational diabetes mellitus (GDM) versus the gold-standard laboratory test. In a prospective cohort observational study at a primary healthcare clinic in Johannesburg, South Africa, pregnant women, excluding known diabetics, were recruited between 2013 and 2016. A 75-g 2-hour oral glucose tolerance test (OGTT) was scheduled at 24-28 gestational weeks. Glucose was measured in venous blood (laboratory) and capillary blood (glucometer). GDM was diagnosed via FIGO criteria. Diagnostic accuracy was evaluated by calculating the sensitivity, specificity, and coefficient of variance (CV) of the glucometer test, and by Bland-Altman plots. Data from 529 women were analyzed. Of these, 141 (26.7%) and 79 (14.9%) were diagnosed with GDM by laboratory and glucometer measurements, respectively. The CV of the glucometer ranged from 15% to 17%. Bland-Altman plots showed a positive bias of the glucometer results at...

Journal of diabetes research, 2017

We aimed to develop a prediction model for the diagnosis of gestational diabetes and to evaluate ... more We aimed to develop a prediction model for the diagnosis of gestational diabetes and to evaluate the performance of published prediction tools on our population. We conducted a cohort study on nondiabetic women < 26 weeks gestation at a level 1 clinic in Johannesburg, South Africa. At recruitment, participants completed a questionnaire and random basal glucose and HbA1c were evaluated. A 75 g 2-hour OGTT was scheduled between 24-28 weeks gestation, as per FIGO guidelines. A score was derived using multivariate logistic regression. Published scoring systems were tested by deriving ROC curves. In 554 women, RBG, BMI, and previous baby ≥ 4000 g were significant risk factors included for GDM, which were used to derive a nomogram-based score. The logistic regression model for prediction of GDM had 0.143, Somer's Dxy rank correlation 0.407, and Harrell's c-score 0.703. HbA1c did not improve predictive value of the nomogram at any threshold (e.g,. at probability > 10%, 25.6% ...

South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde, 2002

To examine the association between measures of obesity and features of the metabolic syndrome in ... more To examine the association between measures of obesity and features of the metabolic syndrome in treated black female hypertensive subjects. Cross-sectional study. An urban primary health care centre in Mamelodi, Pretoria. Women with hypertension and without known diabetes mellitus or secondary causes of hypertension. In total 124 women participated, with a mean age of 56.9 years (standard deviation (SD) 11.0) and mean body mass index (BMI) of 34.1 kg/m2 (SD 8.1). Blood pressure, glucose, insulin and lipid levels. Waist circumference and waist-hip ratio were more strongly associated with insulin, uric acid, glucose and triglycerides than was BMI. Statistically significant associations were found between waist circumference and low high-density lipoprotein HDL cholesterol (standardised regression coefficient -0.006, standard error of the mean (SEM) 0.002), log triglycerides (0.007, SEM 0.003), uric acid (0.002, SEM 0.001) and log insulin (0.012, SEM 0.003). BMI was only significantly...

SADJ : journal of the South African Dental Association = tydskrif van die Suid-Afrikaanse Tandheelkundige Vereniging, 2012

The National Cancer Registry (NCR) of South Africa publishes the pathology-based cancer incidence... more The National Cancer Registry (NCR) of South Africa publishes the pathology-based cancer incidence in the country and is the main cancer data source. The data published by the NCR have been used extensively in the development of the draft national guidelines for cancer prevention and control as well as for cancer research. The list of contributing pathology laboratories is fairly inclusive. Data from the NCR and the University of Limpopo, Department of Oral Pathology for the five years 1997-2001 were combined and then filtered for sites in the oral and oropharyngeal region. Age-Standardised Incidence Rates (ASIR) and the Cumulative Lifetime Risk (LR) for males and females in the different population groups were determined. Comprehensive reporting of oral and oropharyngeal cancer incidence will influence the allocation of government resources for prevention and treatment of oral cancers.

Cardiovascular journal of Africa

We sought to determine whether taking oral erythromycin prior to SPECT myocardial perfusion imagi... more We sought to determine whether taking oral erythromycin prior to SPECT myocardial perfusion imaging with Tc99m-sestamibi would reduce the amount of interfering extra-cardiac activity and improve the image quality. A total of 96 patients who were routinely referred for myocardial perfusion imaging were randomly assigned to one of two groups. Patients in group A received 500 mg of non-enterically coated erythromycin orally one hour prior to image acquisition (45 patients). Patients in group B received diluted lemon juice which comprises the current standard of care in our department (51 patients). A two-day protocol was followed and study participants received the same intervention on both days. Planar images of both the stress and rest images were assessed visually by three experienced nuclear medicine physicians for the presence of interfering extracardiac activity. Physicians were blinded to the detail of the protocol and independently assessed the images. The qualitative results f...

South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde, 2005

Incidence of stroke is increasing in sub-Saharan Africa and stroke prevention is an essential com... more Incidence of stroke is increasing in sub-Saharan Africa and stroke prevention is an essential component of successful stroke management. General practitioners (GPs) are well placed to manage stroke risk factors. To design appropriate strategies for risk factor reduction we need to know the risk factor prevalence in each of the population groups attending GPs. The aim of this study was to establish the prevalence of stroke risk factors in the South African general practice population. We conducted a multicentre, observational study of patients attending general practice in South Africa. Two hundred general practices were randomly selected from lists provided by pharmaceutical representatives. Each GP approached 50 consecutive patients aged 30 years and older. Patients completed an information sheet and the GP documented the patient's risk factors. The resulting sample is relevant if not necessarily representative in a statistical sense. A total of 9 731 questionnaires were return...

South African Family Practice, 2006

This article reports on the prevalence of diabetes in South Africa and gives projections for the ... more This article reports on the prevalence of diabetes in South Africa and gives projections for the epidemic proportions that this disease may take by the year 2030.

Journal of Endocrinology, Metabolism and Diabetes of South Africa, 2008

The prevalence of diabetes for all age groups worldwide was estimated to be 2.8% in the year 2000... more The prevalence of diabetes for all age groups worldwide was estimated to be 2.8% in the year 2000 and is predicted to rise to 4.4% in 2030. The total number of people with diabetes is projected to rise from 171 million in 2000 to 366 million in 2030. 1 Diabetes is complicated by a number of micro-and macrovascular complications including cardiovascular disease, nephropathy, neuropathy and retinopathy. 2,3 Diabetic foot complications contribute significantly to morbidity. Recent data attribute 83% of nontraumatic lower-extremity amputations in the USA to diabetes mellitus. 4 According to the literature 25% of all hospital admissions of patients with diabetes in the USA and UK are for the treatment of infected foot ulcers. Fewer than 14% of patients admitted for diabetic foot complications receive appropriate lower extremity evaluation, and when foot ulcers do develop 1 in 5 of these patients eventually has to undergo an amputation. 5 The rate of secondary amputation of the ipsi-or contralateral limb is as high as 50%. 6 Diabetic foot ulcers have also been recognised as a significant problem in Africa. 7 It is important to recognise that these complications are preventable to a large extent with adequate blood glucose control, regular screening and foot care education. Detection of diabetes-related neuropathy is important, as this nearly always precedes foot ulceration. Patients with a previous history of amputation or foot ulceration are also considered to be at risk for subsequent ulceration. 8 The tertiary care clinic at Pretoria Academic Hospital includes an annual review for diabetes complications as part of its diabetes care plan. This study investigated whether patients with feet at risk for ulceration had better foot care knowledge than patients whose feet were not at risk. Methods Study design This was a cross-sectional descriptive study. Knowledge of foot care in people with diabetes in a tertiary care setting ARTICLE Background. The objective of this study was to investigate levels of foot care knowledge among patients attending the diabetes clinic at Pretoria Academic Hospital by comparing the knowledge of patients with 'at risk' feet (ARF) to those with 'normal/not at risk' feet (NARF) and so assess whether the education effort by the clinic is effective. Methods. Patients attending the clinic completed an interviewer-assisted questionnaire with 11 questions concerning foot care knowledge. A knowledge score for each patient was calculated. Results. Possible scores ranged from 4 to 11 (maximum 11). The mean score for the ARF group was 8.9 (standard deviation (SD) 1.4) (range 4-11) compared with 8.9 (SD 1.4) for the NARF group (range 5-11) (p>0.05). The most substantial difference between the two groups was that the ARF group gave 20% more correct answers than the NARF group with regard to frequency of foot inspection (daily) (p=0.025). Conclusions. Both groups of patients had a reasonable knowledge regarding foot care. The patients at risk were more aware of the need for daily foot inspection.

PLoS ONE, 2014

Background: Although the large majority of persons with diabetes and other non-communicable disea... more Background: Although the large majority of persons with diabetes and other non-communicable diseases (NCDs) lives and dies in low-and middle-income countries, the prevention and treatment of diabetes and other NCDs is widely neglected in these areas. A contributing reason may be that, unlike the impacts of acute and communicable diseases, the demands on resources imposed by diabetes is not superficially obvious, and studies capable of detecting these impacts have not be done. Methods: To ascertain recent use of medical services and medicines and other information about the impact of ill-health, we in 2008-2009 conducted structured, personal interviews with 1,780 persons with diagnosed diabetes (DMs) and 1,770 matched comparison subjects (MCs) without diabetes in Cameroon, Mali, Tanzania and South Africa. We sampled DMs from diabetes registries and, in Cameroon and South Africa, from attendees at outpatient diabetes clinics. To recruit MCs, we asked subjects with diabetes to identify five persons living nearest to them who were of the same sex and approximate age. We estimated diabetes impact on medical services use by calculating ratios and differences between DMs and MCs, testing for statistical significance using two-stage multivariable hurdle models. Findings: DMs consumed 12.95 times more days of inpatient treatment, 7.54 times more outpatient visits, and 5.61 times more medications than MCs (all p,0.001). DMs used an estimated 3.44 inpatient days per person per year, made 10.72 outpatient visits per person per year (excluding traditional healers), and were taking an average of 2.49 prescribed medicines when interviewed. Conclusions: In Sub-Saharan Africa, the relative incremental use of medical care and medicines associated with diagnosed diabetes is much greater than in industrialized countries and in China. Published calculations of the health-system impact of diabetes in Africa are dramatic underestimates. Although non-communicable diseases like diabetes are commonly thought to be minor problems for health systems and patients in Africa, our data demonstrate the opposite.

CardioVascular Journal of Africa, 2010

Introduction: Estimates of left atrial size in patients with suspected cardiac disease play an im... more Introduction: Estimates of left atrial size in patients with suspected cardiac disease play an important role in predicting prognosis and events, as well as treatment decisions. Two methods are commonly used to estimate left atrial size: chest radiography and cardiac ultrasound. This study aims to determine the test characteristics by comparing the use of radiographs to cardiac ultrasound (the gold-standard test). Methods: Data from patients older than 18 years admitted to Steve Biko Academic Hospital during 2000-2003 who had both chest radiographs and cardiac ultrasound were included in this cross-sectional, retrospective analysis. Chest radiographs were classified into three quality classes, and the sub-carinal angle (SCA) and sub-angle distance (SAD) were measured twice in all available radiographs by two observers. Intra-and inter-observer variability (three methods) as well as the predictive value of the carinal angle and sub-angle distance measurements were determined using logistic regression (with left atrial enlargement-determined by ultrasound as comparator). Results: Data for 159 patients were available (154 cardiac ultrasounds and 178 chest radiographs). Intra-observer variability for chest radiograph measurements was low with almost perfect concordance (p = 0.000). Inter-observer variability was higher for supine radiographs. Using logistic regression, a linear model was identified which was statistically significant only for erect radiographs. While goodnessof-fit analysis showed that the model fits the data, performance characteristics were poor, with high sensitivity and low specificity, and an area under the ROC curve of 0.62-0.63, depending on type of radiograph and measurement (SCA or SAD). Linearity in the logit of the dependent variable was assessed, and found to be present at the extremes of SCA measurements for the supine radiograph data and in the first three quartiles for erect radiograph data. A nonlinear model determined by fractional polynomial analysis did not perform significantly better than the original linear model. Cutoff values for the SCA of 72° and 84° (erect and supine radiographs, respectively) were found to give the best compromise between sensitivity and specificity. The corresponding cutoff values for SAD were 24.1 and 26.9 mm. Conclusion: Assessment of either SCA or SAD to determine left atrial size was equivalent and repeatable, both with the same observer and between two observers (less so for supine radiographs). While this measure was precise, it was found not to be very accurate. Therefore, chest radiographs are not reliable in predicting left atrial enlargement.

Curationis, 2002

Although there is general agreement that patient satisfaction is an integral component of service... more Although there is general agreement that patient satisfaction is an integral component of service quality, there is a paucity of South African research on reliable and valid satisfaction measures and the effects of health status on satisfaction. A 25-item patient satisfaction scale was developed and tested for evaluating the quality of health care for black diabetic outpatients. It was hypothesised that: (1) the underlying dimensions of patient satisfaction were interpersonal and organisational; and (2) patients in poor health would be less satisfied with the quality of their care than patients in good health. The questionnaire was administered to 263 black outpatients from Pretoria Academic Hospital and Kalafong Hospital. Factor analysis was conducted on the patient satisfaction scale and three factors, accounting for 71 % of the variance, were extracted.

Health SA Gesondheid, 2009

This review article highlights the key factors that need consideration in planning an effective n... more This review article highlights the key factors that need consideration in planning an effective nutrition education programme for adults with type 2 diabetes mellitus in resource-poor settings. Type 2 diabetes is increasing to epidemic levels globally. Low socioeconomic status is associated with poorer health outcomes and a higher economic burden. Individuals with diabetes cite dietary adherence as the most diffi cult self-care area. Effective nutrition education achieves the desired goals and outcomes, which include appropriate change in dietary behaviour, improved glycaemic control, plasma lipid levels, blood pressure and body weight, as well as improved potential mediators (knowledge, skills and attitudes). Elements that contribute to a successful nutrition education programme include interventions tailored to the needs, abilities and socio-cultural context of the target group, the active involvement of the patient, a behaviour-focused approach based on appropriate theory, suitable delivery methods and individual/group approaches. Adequate contact time with an educator (> 10 hours), the educator's competence, provision of social support and follow-up intervention are also crucial. Effectively educating diabetic individuals from resource-poor settings in nutrition is a challenging task. It needs innovative and skilled educators who are sensitive to the unique needs of the target group and who use appropriate approaches to address these needs. OPSOMMING Hierdie artikel beklemtoon die sleutelfaktore wat in oorweging geneem moet word wanneer 'n effektiewe voedingsopleidingprogram vir volwassenes met tipe 2-diabetes uit hulpbron-arm agtergronde beplan word. Tipe 2-diabetes is besig om globaal tot epidemiese vlakke toe te neem. Lae sosio-ekonomiese status word geassosieer met swakker gesondheidsresultate en 'n hoër ekonomiese las. Dieetnakoming word deur persone met diabetes as die moeilikste selfversorgingsgebied uitgewys. Doeltreffende voedingsopleiding bereik die gewenste doelwitte en resultate wat toepaslike veranderings in dieetgedrag, verbeterde glisemiese beheer, verbeterde bloedlipiede, bloeddruk en liggaams-gewig, en verbeterde potensiële bemiddelaars (kennis, vaardighede en houdings), insluit. Elemente wat tot 'n suksesvolle voedingsopleidingprogram bydra, sluit ingrypings in wat geskoei is op die behoeftes, vaardighede en sosiaal-kulturele konteks van die teikengroep, aktiewe betrekking van die pasient, gebruik van 'n benadering wat ingestel is op gedrag en gegrond is op toepaslike teorie, toepaslike metodes van afl ewering en individuele/groepbenaderings, geskikte duur en kontaktyd (> 10 uur), een wat vir sosiale ondersteuning en opvolgintervensie sorg, en deur 'n bedrewe verskaffer bemiddel word. Om diabetiese individue uit hulpbron-arm agtergronde op te lei in voeding is 'n uitdagende taak wat vindingryke en bedrewe opvoeders verg. Hierdie opvoeders moet sensitief wees vir die unieke behoeftes van die teikengroep en toepaslike benaderings volg om genoemde behoeftes aan te spreek. Patient education, also referred to as diabetes self-management education (DSME), is a cornerstone of treatment for diabetes (ADA 2007a:30). Diabetes education is the process of providing the diabetic with the knowledge, skills and motivation that are needed to perform self-care, manage crises and make the lifestyle changes required to successfully manage their condition (Clement 1995:18). An extensive body of literature exists that demonstrates that DSME signifi cantly improves health outcomes (Asha,

Thrombosis and …, 2008

Diabetic subjects have been shownt oh avea ltered fibrin network structures.One proposedmechanism... more Diabetic subjects have been shownt oh avea ltered fibrin network structures.One proposedmechanism forthis is non-enzymaticglycation of fibrinogendue to highbloodglucose.We investigatedwhether glycaemic control would result in altered fibrin networkstructures duetodecreasedfibrinogen glycation. Tw enty uncontrolledtype 2diabetic subjects were treatedwith insulin in ordert oa chieve glycaemic control. Tw enty age-a nd bodymass index(BMI)-matched non-diabetic subjects were included as ar eference group.Purified fibrinogen, isolated from plasma sampleswas usedfor analysis.Therewas asignificant decrease in fibrinogen glycation (6.81 to 5.02mol glucose/mol fibrinogen) with acorresponding decrease in rate of lateralaggregation (5.86 to 4.62) and increasedpermeability(2.45 to 2.85 x 10-8 cm 2)a nd lysisr ate (3.08 to 3.27 µm/min) in the diabetic subjects afterglycaemic control.Thesevariablescorrelated with Keywords Diabetes,fibrin network,fibrinogen glycation,glycaemic control, hyperglycaemia markerso fg lycaemic control. Fibrin clots of non-diabetic subjects had as ignificantly higherr atio of inelastic to elastic deformation than thed iabetic subjects (0.10 vs.0.09).Although there was no difference in median fiber diameterbetween diabetic and non-diabetic subjects,there was asmallincrease in the proportion of thicker fibers in the diabetic samplesa fter glycaemic control.Results from SDS-PAGEindicated no detectable difference in factor XIIIa-crosslinking of fibrin clotsbetween uncontrolled and controlled diabetic samples. Diabetic subjects mayhavealtered fibrin networkf ormation kineticswhich contributes to decreasedp ores ize and lysisr ate of fibrinc lots. Achievement of glycaemiccontroland decreasedfibrinogen glycation levelimprovespermeabilityand lysisratesinapurified fibrinogen model.