Cognitive and Motor Development in 3- to 6-Year-Old Children Born to Mothers with Hyperglycaemia First Detected in Pregnancy in an Urban African Population

OBJECTIVES

Hyperglycaemia first detected in pregnancy (HFDP), on the rise in urban sub-Saharan Africa (SSA), may negatively impact foetal neurodevelopment, with potential long-term cognitive consequences for the child. Data on this association from SSA is lacking, and we aimed to investigate the association in 3- to 6-year-old children in Soweto, South Africa.

METHODS

In this comparative study, we compared cognitive skills measured with the Herbst Early Childhood Development Criteria test in 95 children born to mothers with HFDP and 99 participants unexposed to maternal HFDP. Fine and gross motor skills were secondary outcomes. Ordinal regression analysis with known confounders was performed for children born at-term.

RESULTS

Of children exposed to HFDP born at-term, 24.3% scored 'high' and 25.7% scored 'low' in the cognitive subsection of the test, as opposed to 37.7% and 12.9% in the HFDP-unexposed group, respectively. In ordinal regression, exposed participants had a significantly lower odds of scoring in a higher cognitive category when adjusting for maternal confounders and socio-economic status (OR 0.33, 95% CI 0.15-0.74, p = 0.007). No difference was found in gross motor development between the two groups; differences in fine motor development were attenuated after adjustment for maternal pregnancy factors and household socioeconomic status (OR 0.62, 95% CI 0.28-1.37, p = 0.239).

CONCLUSIONS FOR PRACTICE

Exposure to HFDP was negatively associated with cognitive development at preschool age. Optimising maternal (preconception) health and early childhood cognitive stimulation could help more children reach their developmental potential.

HIV treatment is associated with a two-fold higher probability of raised triglycerides: Pooled Analyses in 21 023 individuals in sub-Saharan Africa

BACKGROUND

Anti-retroviral therapy (ART) regimes for HIV are associated with raised levels of circulating triglycerides (TG) in western populations. However, there are limited data on the impact of ART on cardiometabolic risk in sub-Saharan African (SSA) populations.

METHODS

Pooled analyses of 14 studies comprising 21 023 individuals, on whom relevant cardiometabolic risk factors (including TG), HIV and ART status were assessed between 2003 and 2014, in SSA. The association between ART and raised TG (>2.3 mmol/L) was analysed using regression models.

FINDINGS

Among 10 615 individuals, ART was associated with a two-fold higher probability of raised TG (RR 2.05, 95% CI 1.51-2.77, I2=45.2%). The associations between ART and raised blood pressure, glucose, HbA1c, and other lipids were inconsistent across studies.

INTERPRETATION

Evidence from this study confirms the association of ART with raised TG in SSA populations. Given the possible causal effect of raised TG on cardiovascular disease (CVD), the evidence highlights the need for prospective studies to clarify the impact of long term ART on CVD outcomes in SSA.

High prevalence of "non-dipping" blood pressure and vascular stiffness in HIV-infected South Africans on antiretrovirals

BACKGROUND

HIV-infected individuals are at increased risk of tissue inflammation and accelerated vascular aging ('inflamm-aging'). Abnormal diurnal blood pressure (BP) rhythms such as non-dipping may contribute to an increased risk of cardiovascular and cerebrovascular events in HIV infected individuals. However, little data exists on ambulatory blood pressure (ABP) and measures of vascular stiffness in the black African HIV infected population.

METHODS

This is a cross-sectional analysis of otherwise well, HIV infected outpatients on ART for >5 years. Study assessments included: 24hr ABP monitoring, pulse wave velocity (PWV) and central aortic systolic pressure (CASP) using a AtCor Medical Sphygmocor device, fasting lipogram, oral glucose tolerance test, high-sensitivity C-reactive protein (hsCRP) and anthropometric data. Patients completed a questionnaire of autonomic symptoms. CD4+ counts and viral loads were obtained from the National Laboratory results system.

RESULTS

Sixty seven black participants were included in the analysis of whom 91% (n = 61) were female with a mean age of 42.2 ± 8.6 years. The median duration on ART was 7.5 years (IQR = 6-10), 84% were virally supressed and the median CD4 count was 529.5cells/mm3 (IQR = 372.0-686.5). The majority (67%) were classified as overweight and 76% had an increased waist circumference, yet only 88% of participants were normotensive. A hsCRP level in the high cardiovascular risk category was found in 68% of participants. The prevalence of non-dipping BP was 65%. Interestingly, there was no association on multivariable analysis between dipping status and traditional risk factors for non-dipping BP, such as: obesity, autonomic dysfunction and older age.

CONCLUSION

This relatively young cross-sectional sample of predominantly normotensive, but overweight black women on effective ART >5 years showed: a high prevalence of non-dipping BP, inflammation and vascular stiffness. Causality cannot be inferred but cardiovascular risk reduction should be emphasized in these patients.

Salivary Cortisol and Cortisone do not Appear to be Useful Biomarkers for Monitoring Hydrocortisone Replacement in Addison's Disease

Salivary cortisol has been used to monitor hydrocortisone replacement in patients with Addison's disease (AD). Since salivary cortisol is metabolised to salivary cortisone, it may be an adjunctive analyte to assess adequacy of hydrocortisone replacement in patients with AD. We aimed to characterise the exposure of salivary cortisol and cortisone in patients and healthy controls. We measured salivary cortisol and cortisone by liquid chromatography-tandem mass spectrometry and constructed a day curve (08:00 until 24:00 h) with 16 time points in 25 AD patients taking their usual hydrocortisone dose and in 26 healthy controls. The median (interquartile range) area under the curve (AUC) for cortisol was not different for patients, compared with controls [55.63 (32.91-151.07) nmol*min*l^-1 vs. 37.49 (27.41-52.00) nmol*min*l^-1; p=0.098, respectively], whereas the peak cortisol C_max was higher in patients [32.61 (5.75-146.19) nmol/l vs. 8.96 (6.96-12.23) nmol/l; p=0.013], compared with controls. The AUC for cortisone [23.65 (6.10-54.76) nmol*min*l^-1 vs. 227.73 (200.10-280.52) nmol*min*l^-1; p≤ 0.001, respectively], and peak cortisone C_max was lower in patients than in controls [11.11 (2.91-35.85) nmol/l vs. 33.12 (25.97-39.95) nmol/l; p=0.002]. The AUC for salivary cortisol and salivary cortisone were not correlated with any measures of hydrocortisone dose. The time-course and AUC of salivary cortisol were similar between Addison's patients and healthy controls. Patients had substantially lower salivary cortisone AUC, compared to healthy controls. Salivary cortisol AUC and pharmacokinetics were not related to hydrocortisone dose and thus are not likely useful markers for the adequacy of hydrocortisone replacement.

The need for an integrated approach for chronic disease research and care in Africa

With the changing distribution of infectious diseases, and an increase in the burden of non-communicable diseases, low- and middle-income countries, including those in Africa, will need to expand their health care capacities to effectively respond to these epidemiological transitions. The interrelated risk factors for chronic infectious and non-communicable diseases and the need for long-term disease management, argue for combined strategies to understand their underlying causes and to design strategies for effective prevention and long-term care. Through multidisciplinary research and implementation partnerships, we advocate an integrated approach for research and healthcare for chronic diseases in Africa.

H3Africa multi-centre study of the prevalence and environmental and genetic determinants of type 2 diabetes in sub-Saharan Africa: study protocol

The burden and aetiology of type 2 diabetes (T2D) and its microvascular complications may be influenced by varying behavioural and lifestyle environments as well as by genetic susceptibility. These aspects of the epidemiology of T2D have not been reliably clarified in sub-Saharan Africa (SSA), highlighting the need for context-specific epidemiological studies with the statistical resolution to inform potential preventative and therapeutic strategies. Therefore, as part of the Human Heredity and Health in Africa (H3Africa) initiative, we designed a multi-site study comprising case collections and population-based surveys at 11 sites in eight countries across SSA. The goal is to recruit up to 6000 T2D participants and 6000 control participants. We will collect questionnaire data, biophysical measurements and biological samples for chronic disease traits, risk factors and genetic data on all study participants. Through integrating epidemiological and genomic techniques, the study provides a framework for assessing the burden, spectrum and environmental and genetic risk factors for T2D and its complications across SSA. With established mechanisms for fieldwork, data and sample collection and management, data-sharing and consent for re-approaching participants, the study will be a resource for future research studies, including longitudinal studies, prospective case ascertainment of incident disease and interventional studies.

Male and female hypogonadism are highly prevalent in South Africans with Addison's disease

Hypogonadism may complicate Addison's disease (primary hypoadrenalism), but prevalence and metabolic sequelae of hypogonadism in Addison's disease are poorly described. We recruited patients from the South African Addison's disease national registry who received stable replacement doses of hydrocortisone and had no acute illness. Male biochemical testosterone deficiency was defined as an early morning basal testosterone<9.9 nmol/l and premature ovarian failure (POF) when menopause occurred before 40 years of age. Cardiometabolic risk variables were measured in males only. Male hypogonadism prevalence was 33% (14/42), and 10 patients had newly diagnosed hypogonadism. Two untreated patients had elevated FSH or LH (>10 or 12 IU/l). Testosterone deficiency did not correlate with age, disease duration or hydrocortisone dose. Untreated male hypogonadal subjects had a higher (mean ± standard deviation) BMI compared to eugonadal subjects 29.2 ± 4.9 kg/m(2) vs. 24.7 ± 3.4 kg/m(2) (p=0.01) and a higher median (interquartile range) high-sensitive-CRP 6.4 (2.5-14.0) mg/l vs. 1.45 (0.6-2.8) mg/l (p=0.002). There were no differences between the 2 groups in lipids, lipoproteins and fasting glucose. The median (interquartile range) DHEAS was lower in the hypogonadal 0.31 (0.27-0.37) μmol/l, compared with the eugonadal group 0.75 (0.50-1.51) μmol/l (p=0.005). POF was documented in 11% of female patients. Male testosterone deficiency was highly prevalent in this cohort and was primarily due to secondary hypogonadism. Only BMI and hs-CRP were increased in untreated male hypogonadal subjects. Male and female hypogonadism appears to be a common complication of Addison's disease and may contribute to its morbidity.

Glucocorticoid receptor gene expression in adipose tissue and associated metabolic risk in black and white South African women

BACKGROUND

Black women have lower visceral adipose tissue (VAT) but are less insulin sensitive than white women; the mechanisms responsible are unknown.

OBJECTIVE

The study aimed to test the hypothesis that variation in subcutaneous adipose tissue (SAT) sensitivity to glucocorticoids might underlie these differences.

METHODS

Body fatness (dual energy X-ray absorptiometry) and distribution (computerized tomography), insulin sensitivity (SI, intravenous and oral glucose tolerance tests), and expression of 11β-hydroxysteroid dehydrogenase-1 (11HSD1), hexose-6-phosphate dehydrogenase and glucocorticoid receptor-α (GRα), as well as genes involved in adipogenesis and inflammation were measured in abdominal deep SAT, superficial SAT and gluteal SAT (GLUT) depots of 56 normal-weight or obese black and white premenopausal South African (SA) women. We used a combination of univariate and multivariate statistics to evaluate ethnic-specific patterns in adipose gene expression and related body composition and insulin sensitivity measures.

RESULTS

Although 11HSD1 activity and mRNA did not differ by ethnicity, GRα mRNA levels were significantly lower in SAT of black compared with white women, particularly in the GLUT depot (0.52±0.21 vs 0.91±0.26 AU, respectively, P<0.01). In black women, lower SAT GRα mRNA levels were associated with increased inflammatory gene transcript levels and abdominal SAT area, and reduced adipogenic gene transcript levels, VAT/SAT ratio and SI. Abdominal SAT 11HSD1 activity associated with increased VAT area and decreased SI in white, but not in black women.

CONCLUSIONS

In black SA women, downregulation of GRα mRNA levels with obesity and reduced insulin sensitivity, possibly via increased SAT inflammation, is associated with reduced VAT accumulation.

Increased cardiovascular risk in South African patients with Addison's disease

Patients with Addison's disease (AD) are believed to be at risk for cardiovascular disease (CVD). South Africa, like the rest of the developing world is experiencing an increase in CVD and patients with AD may be at double the risk of their peers. We wished to explore AD patients' CVD risk factors. A cross-sectional nationwide study in South Africa of patients with AD was conducted. A cohort of 147 patients with AD and 147 healthy control subjects were matched by age, gender, ethnicity, and BMI as far as was possible. Lipoproteins and highly-sensitive C-reactive-protein (hs-CRP) were the main outcome measures. AD patients had significantly higher triglycerides; (p=0.001), lower HDLC (p<0.001), higher hs-CRP (p<0.001), and more small dense LDL; (p=0.002) than controls. Nonesterified fatty acids were lower in patients (p<0.001). Approximately 65% [95% confidence interval (CI 55.6-72.4%)] had hypercholesterolaemia, 75% (CI 64.8-81.2%) had low HDLC, and 75% (CI 68.0-84.1%) had a higher LDLC. Thirteen percent of AD patients had diabetes mellitus, but none of the risk factors differed from the nondiabetics. Only HDLC correlated positively with daily hydrocortisone dose (r=0.32; p=0.005). In conclusion dyslipidaemia is common in South African AD patients; CVD risk assessment and intervention are probably warranted in the management of these patients.

Investigation of glucocorticoid receptor polymorphisms in relation to metabolic parameters in Addison's disease

BACKGROUND

Uncertainty exists whether glucocorticoid receptor (GCR) polymorphisms play a role in steroid-related side effects in Addison's disease (AD) patients on hydrocortisone. The polymorphisms Bcll and N363S appear to increase sensitivity to cortisol, while the ER22/23EK polymorphism has been associated with resistance to cortisol.

METHOD

One hundred and forty seven AD patients, and gender, and ethnicity-matched controls were recruited in South Africa. Three polymorphisms in the GCR were studied, using PCR followed by restriction fragment length analysis. Associations with BMI, lipids, glucose and inflammatory markers were investigated.

RESULTS

In both patients and controls, the Bcll polymorphism occurred more frequently in whites than in other ethnic groups studied but was not associated with any of the metabolic parameters tested. The ER22/23EK polymorphism was associated with an increased BMI in both patients (29.4 vs 24.7  kg/m²) and control subjects (26.3 vs 24.2  kg/m²). The ER22/23EK polymorphism was also associated with lower LDL cholesterol in control subjects (3.46 vs 3.93  mmol/l) and in patients (3.52 vs 4.10  mmol/l). N363S was associated with increased BMI in controls 29.9  kg/m² vs wild type 24.8  kg/m². Median hydrocortisone doses were greater in patients heterozygous for either ER22/23EK 30.0  mg or N363S 25.0  mg polymorphisms than in wild type patients 20.0  mg (both comparisons).

CONCLUSION

Alterations in lipids, BMI and hydrocortisone dose were associated with two polymorphisms. Further larger studies are warranted to corroborate these findings.

Salivary cortisol day curves in Addison's disease in patients on hydrocortisone replacement

Using salivary cortisol (SC) measurements, cortisol exposure in Addison's disease patients on hydrocortisone replacement was determined and compared with healthy controls. Cortisol pharmacokinetics was assessed in 31 patients with Addison's disease on replacement hydrocortisone doses (median daily dose 20 mg; range 5-50 mg) and 30 healthy control subjects. Saliva samples (n=16) were collected between 08:00 and 00:00 h in 1 day, using a passive drool technique. Cortisol exposure was evaluated by noncompartmental approach. In the patients, cortisol exposure was significantly higher than in controls: median inter-quartile range (IQR) peak cortisol (C(max)) 174.5 (59.3-837.0) vs. 6.50 (4.7-19.3) nmol/l, p=0.0001; area under the curve (AUC) 390.1 (177.1-928.9) vs. 21.4 (14.6-28.4) minutes*nmol/l, p=0.0001, trough cortisol level (C(min)) 0.49 (0.49-0.96) vs. 0.49 (0.49-0.49) nmol/l, p=0.02, occurring at 480.0 (0.1-660.0) vs. 405.0 (180.0-570.0) min, p=0.56. First peak cortisol was 174.5 (53.0-754.7) vs. 6.27 (3.90-8.47) nmol/l, p=0.0001 and second peak cortisol 18.90 (5.22-76.9) vs. 3.12 (1.76-4.79) nmol/l, p=0.0001. The time to first peak cortisol differed between the 2 groups, 30 (30-75) vs. 0.1 (0.1-30) minutes; p=0.0001. At doses studied, hydrocortisone replacement therapy results in cortisol pharmacokinetics being markedly different from endogenous cortisol profiles in healthy control subjects. Addison's disease patients had significantly higher SC levels compared to healthy control subjects.

Site-specific differences in bone mineral density in black and white premenopausal South African women

SUMMARY

We examined ethnic differences in bone mineral density (BMD) and the contribution of body composition, lifestyle and socioeconomic factors in South African women. Femoral neck and total hip BMD were higher, but lumbar spine BMD was lower in black women, with body composition, lifestyle and socioeconomic status (SES) factors contributing differently in ethnic groups.

INTRODUCTION

There is a paucity of data on the relative contribution of body composition, lifestyle factors and SES, unique to different ethnic groups in South Africa, to BMD. We examined differences in femoral neck (FN), total hip (TH) and lumbar spine (LS) BMD between black and white premenopausal South African women and the associations between BMD and body composition, lifestyle factors and SES in these two ethnic groups.

METHODS

BMD and body composition were measured in 240 black (27 ± 7; 18-45 years) and 187 white (31 ± 8; 18-45 years) women using dual-energy X-ray absorptiometry. Questionnaires were administered to examine SES, physical activity and dietary intake.

RESULTS

After co-varying for age, FN and TH were higher in black than white women (FN 0.882 ± 0.128 vs. 0.827 ± 0.116 g/cm(2), P < 0.001; TH 0.970 ± 0.130 vs. 0.943 ± 0.124 g/cm(2), P = 0.018). When adjusting for ethnic differences in body composition, LS was higher in white than black women. In black women, fat-free soft tissue mass, SES and injectable contraceptive use explained 33-42% of the variance in BMD at the hip sites and 22% at the LS. In white women, fat-free soft tissue mass and leisure activity explained 24-30% of the variance in BMD at the hip sites, whereas fat mass, leisure activity and oral contraceptive use explained 11% of the variance at the LS.

CONCLUSION

FN and TH BMD were higher, but LS BMD was lower in black than white South African women with body composition, lifestyle and SES factors contributing differently to BMD in these women.

Abnormal glucose metabolism in non-diabetic patients presenting with an acute stroke: prospective study and systematic review

BACKGROUND

Non-diabetic patients presenting with an acute stroke often have hyperglycaemia. In most populations it is unknown whether the hyperglycaemia is transient and due to the acute stress response or whether it represents undiagnosed abnormal glucose metabolism.

AIM

To evaluate the prevalence and predictors of persistent hyperglycaemia in non-diabetic patients with an acute stroke.

DESIGN

Prospective observational study.

METHODS

Non-diabetic patients over 40 years old with an acute stroke were enrolled over a 2-year period. On admission patients were evaluated with an HbA(1c) and a 75 g oral glucose tolerance test (OGTT). The OGTT was repeated 3 months later. A meta-analysis was performed to interpret our results in the context of published data.

RESULTS

One hundred and seven patients were analysed. On admission 26 (24%) patients had diabetes, 39 (37%) had impaired glucose tolerance and 42 (39%) had normal glucose tolerance. Forty-four (68%) patients with hyperglycaemia on admission were re-investigated at least 3 months after discharge. Of these, 6 (14%) had diabetes, 12 (27%) had impaired glucose tolerance and 26 (59%) had normal glucose tolerance. A 2-h post-load glucose value >or=10 mmol/l predicted persistent hyperglycaemia with 72.2% sensitivity, 65.4% specificity and a positive predictive value and negative predictive value of 59.1 and 77.3%, respectively. A meta-analysis of prevalence data of impaired glucose metabolism in non-diabetic individuals 3 months after having had an acute stroke revealed a combined prevalence of 58% (95% confidence interval 25.4-90.5%).

CONCLUSION

In this study hyperglycaemia in the setting of an acute stroke was transient in the majority of patients.

Metabolic syndrome and alanine aminotransferase: a global perspective from the NAVIGATOR screening population

AIMS

Non-alcoholic fatty liver disease (NAFLD) is associated with features of the metabolic syndrome (MetS) and may be an expression of the syndrome within the liver. Using screening data from the Nateglinide And Valsartan in Impaired Glucose Tolerance Outcomes Research (NAVIGATOR) study (n = 42 149), we examined whether alanine aminotransferase (ALT), a biomarker for NAFLD, clustered with features of MetS and whether the clusters differed across global geographic regions.

METHODS

Exploratory factor analysis using principle components analysis was applied to data drawn from the NAVIGATOR screening population (n = 41 111). Demographic data, anthropomorphic measurements and blood pressure (BP) collected during the screening visit, as well as blood samples analysed for ALT, total cholesterol, triglycerides, high-density lipoprotein, low-density lipoprotein, and fasting and 2-h glucose measures after an oral glucose tolerance test were used for our analysis.

RESULTS

Two factors, interpreted as lipid (Factor 1), and BP/obesity (Factor 2) were identified, explaining approximately 50% of the variance in the overall population. Similar patterns of aggregation were reproducible across all geographic regions except Asia, where fasting glucose loaded more consistently on Factor 1. ALT loaded with mean arterial pressure, fasting glucose and waist circumference except in Asia, where it loaded only with mean arterial pressure and waist circumference.

CONCLUSIONS

ALT aggregated with components of MetS, and the pattern of aggregation of ALT with other features of MetS was similar across regions except Asia, possibly indicating a different pathophysiology for NAFLD in Asia. Predictive models of NAFLD may need to be adjusted for regional and ethnic differences.

Diabetes in Africa: epidemiology, management and healthcare challenges

Diabetes is an increasing problem in sub-Saharan Africa. Type 2 diabetes, the most common form, is becoming more prevalent owing to rising rates of obesity, physical inactivity and urbanisation. Type 1 diabetes exists in two major forms in the region: type 1A or autoimmune and type 1B or ketosis-prone type 2 diabetes. At present there are scanty epidemiological data on either. The current morbidity of diabetes is primarily due to the high rates of microvascular complications, while macrovascular complications, once rare, are becoming more common, particularly in the urban setting. Further, despite the HIV epidemic, the total number of people with diabetes in the region is expected to grow because of changing demography. A concerted multisectoral effort will be critical to ensuring improvement in healthcare delivery for people with diabetes in the region.

Early life and current determinants of bone in South African children of mixed ancestral origin

BACKGROUND

The influence of early life factors on the bone mineral density of children has been identified, however the contribution of these determinants may vary.

AIM

The study investigated determinants of bone mineral content (BMC) in South African children of mixed ancestral origin.

SUBJECTS AND METHODS

Early life data including birth weight, maternal alcohol consumption and smoking during pregnancy were collected on 9-year-old children of mixed ancestral origin (n = 64). Grip strength was measured, and physical activity, housing density and dietary data were collected. Whole body BMC (WB BMC), fat-free soft tissue and fat tissue were measured using dual energy X-ray absorptiometry.

RESULTS

Maternal alcohol consumption during pregnancy was associated with WB BMC, however after adjusting for possible confounders, this was no longer significant. When combined with gender, gestational age and maternal BMC in a multiple regression, maternal alcohol consumption during pregnancy could explain 20% of the variance in the WB BMC, however when current height was included in the model, the contribution of the other factors was insignificant. There was however a significant correlation between current height and birth weight (r = 0.34; p < 0.01) and alcohol consumption during pregnancy (r = 0.34; p < 0.05). A model consisting of current factors such as age, weight, gender, grip strength and calcium intake was able to explain 81.5% of the variance. Housing density was negatively correlated with WB BMC (r =-0.11; p = 0.05).

CONCLUSION

These data suggest that although early life factors may contribute indirectly to the bone mass of children of mixed ancestral origin, the contribution of current factors is greater. In addition, environmental factors such as housing density have a direct effect on bone mass, independent of body size.

Hyperglycaemic emergency admissions to a secondary-level hospital - an unnecessary financial burden

BACKGROUND AND OBJECTIVES

Diabetes affects approximately 1 million South Africans. Hospital admissions, the largest single item of diabetes expenditure, are often precipitated by hyperglycaemic emergencies. A recent survey of a 200- bed hospital, serving approximately 1.3 million Cape Town residents, showed that hyperglycaemic emergencies comprised 25.6% of high-care unit admissions. A study was undertaken to determine the reasons for, and financial cost of, these admissions.

METHODS

All hyperglycaemic admissions during a 2-month period (1 September - 31 October 2005) were surveyed prospectively. Admissions were classified using the American Diabetes Association classification of hyperglycaemic emergencies. Demographic data, and the reason for, duration of and primary outcome of admission, were recorded. The following costs per admission were calculated using publicsector pricing: (i) total costs; (ii) patient-specific costs; (iii) nonpatient- specific costs; and (iv) capital costs.

RESULTS

Sepsis (36%), non-compliance with therapy (32%) and a new diagnosis of diabetes (11%) were the predominant reasons for admission of 53 hyperglycaemic emergency cases. Mean duration of hospital stay was 4 days, with an in-hospital mortality of 7.5%. Mean cost per admission was R5 309. Clinical staff (25.8%), capital (25.6%) and overhead (34%) costs comprised 85.4% of expenditure.

DISCUSSION AND RECOMMENDATIONS

Hyperglycaemic admissions, costing more than R5 300 per patient, represent a health burden that has remained unchanged over the past 20 years. Urgently required primary care preventive strategies include early diagnosis of diabetes, timely identification and treatment of precipitating causes, specifically sepsis, and education to improve compliance.

Association between insulin-like growth factor-1, insulin-like growth factor-binding protein-1 and leptin levels with nutritional status in 1–3-year-old children, residing in the central region of Limpopo Province, South Africa

The present study evaluated levels of growth factors and their associations with nutritional status with emphasis on stunting in children at 1 and 3 years of age. A follow-up study on a birth cohort (n 219) of children from villages in the central region of the Limpopo Province was undertaken. Of the original cohort, 156 and 162 could be traced and assessed at ages 1 and 3 years, respectively. Data collected included socio-demographic characteristics, anthropometric measurements, dietary intake and fasting blood (collected from 116 and 145 children at 1 and 3 years, respectively) for growth factor analysis (insulin-like growth factor (IGF)-1, IGF binding protein (BP)-1, IGFBP-3, leptin, glucose and insulin). At 1 year it was found that stunted children had lower leptin levels while their IGFBP-1 levels were higher than that in normal children. These differences were, however, not observed at 3 years. Furthermore at 1 year the biochemical parameters were more related to length measures whereas at 3 years the parameters were more associated with weight measures. The observed stunting in this group of children may be a result of chronic undernutrition resulting in long-term growth faltering which is already evident at 1 year. Thus the observed phenomenon might be an adaptive mechanism adopted by children's metabolic processes as they grow up in an environment with inadequate essential nutrients due to poor weaning practices and consumption of a diet of poor quality, resulting in them gaining more weight at the expense of linear growth.

A 10-year retrospective analysis of pregnancy outcome in pregestational Type 2 diabetes: comparison of insulin and oral glucose-lowering agents

AIMS

To review the use of oral glucose-lowering agents (OGLA) in pregnant women with Type 2 diabetes mellitus.

METHODS

Retrospective analysis of outcomes and their predictors in singleton pregnancies > or = 24 weeks managed at Groote Schuur hospital, Cape Town, South Africa from 1991 to 2000. There were 379 pregnancies, subdivided into three groups according to therapy: OGLA alone, converted from OGLA to insulin, insulin alone or converted from diet alone to insulin. The OGLA used were metformin and glibenclamide.

RESULTS

Mean glycated haemoglobin (HbA(1c)) was similar at booking and throughout pregnancy in all groups. In the OGLA alone, converted from OGLA to insulin and insulin alone/converted from diet alone to insulin groups, fetal anomaly rates were comparable: 5.7%, 2.0% and 0.0%, P = 0.2, respectively; whereas perinatal mortality rates (per 1000 births) were: 125, 28, 33, P = 0.003, respectively. Booking HbA(1c) was independently associated with fetal anomaly [odds ratio (OR) 1.48; 95% confidence interval (CI) 1.11, 1.97; P = 0.006]. The specific OGLA used in the first trimester was not associated with the occurrence of fetal anomaly. Last HbA(1c) (OR 1.65; 95% CI 1.16, 2.42; P = 0.005) and fetal anomaly (OR 15.18; 95% CI 2.43, 93.37; P = 0.005) were independently associated with perinatal mortality. Conversion from OGLA to insulin was protective for perinatal mortality compared with OGLA alone treatment (OR 0.220; 95% CI 0.061, 0.756; P = 0.024). No perinatal mortality was observed in women on metformin alone.

CONCLUSIONS

These data suggest that metformin and glibenclamide are not teratogenic but that it is advisable to replace OGLA, in particular glibenclamide, with insulin when women book for pregnancy care to reduce perinatal mortality rates.

Prevalence of gestational diabetes mellitus and the effect of weight on measures of insulin secretion and insulin resistance in third-trimester pregnant rural women residing in the Central Region of Limpopo Province, South Africa

AIMS

To examine the prevalence of gestational diabetes in third-trimester pregnant women as well as to assess their insulin secretion and insulin resistance (IR).

METHODS

Third-trimester pregnant women (n= 262) attending antenatal care at local clinics in the central region of the Limpopo Province underwent a 2-h oral glucose tolerance test (OGTT) with blood collected at 0, 30 and 120 min. Glucose and insulin were measured.

RESULTS

The prevalence of gestational impaired glucose tolerance (GIGT) and gestational diabetes mellitus (GDM) was 8.8% (7.3% GIGT; 1.5% GDM). Women with GIGT/GDM were significantly older and had more children compared with women with a normal response to the OGTT. Homeostasis model assessment(HOMA)-IR and fasting insulin were lower in the GIGT/GDM group compared with the normal group, as were measures of insulin secretion (HOMA B-cell function and insulinogenic index). Furthermore, women with body mass index (BMI)> or =30.0 kg/m2 were significantly older and had higher parity, systolic and diastolic blood pressure measurements than those with BMI 25.0-29.9 kg/m2 and BMI < 25.0 kg/m2. However,increased BMI was not associated with an increased risk of GIGT/GDM.

CONCLUSION

The present study shows that there is a high prevalence of GIGT/GDM, with most women having IGT. The GIGT/GDM present in these women is characterized by increased insulin sensitivity accompanied by reduced pancreatic B-cell function. Additionally, heavier women appear to have increased first phase insulin secretion, suggesting the presence of insulin resistance.

Glucocorticoid metabolism within superficial subcutaneous rather than visceral adipose tissue is associated with features of the metabolic syndrome in South African women

OBJECTIVE

Glucocorticoid hyperactivity in adipose tissue, due to up-regulation of local glucocorticoid reactivation by 11beta-hydroxysteroid dehydrogenase-1 (11HSD1) or of glucocorticoid receptors (GR), may underpin susceptibility to the metabolic syndrome. This hypothesis has been tested extensively in subcutaneous adipose tissue (SAT) but inadequately in visceral adipose tissue (VAT). The aim of the study was therefore to examine expression of 11HSD1, GRalpha and hexose-6-phosphate dehydrogenase (H6PDH), which supplies cofactor for 11HSD1, in abdominal adipose tissue compartments and to characterize their relation to metabolic syndrome parameters.

DESIGN AND SUBJECTS

A cross-sectional study including 26 premenopausal South African women.

MEASUREMENTS

Biopsies were taken for measurement of mRNA levels by real-time polymerase chain reaction (RT-PCR) and 11HSD1 activity from VAT, and deep and superficial SAT compartments during elective surgery. Prior to surgery, blood pressure, blood lipid profile, body composition [by dual X-ray absorptiometry (DEXA) scan], body fat distribution [by computed tomography (CT) scan], and glucose tolerance were determined.

RESULTS

11HSD1 activity (P < 0.01) was higher in VAT than SAT, but 11HSD1 and GRalpha mRNA levels were not statistically different between compartments. 11HSD1 mRNA levels in superficial SAT correlated with VAT volume (R = 0.57, P < 0.01), insulin sensitivity calculated from the oral glucose tolerance test (OGTT) (R = -0.52, P < 0.016) and blood pressure (R = 0.48, P < 0.016). Apart from a correlation between deep SAT 11HSD1 activity and blood pressure (R = 0.72, P < 0.01), glucocorticoid action in deep SAT and VAT depots was not significantly associated with any metabolic syndrome parameters.

CONCLUSION

Increased capacity for glucocorticoid regeneration in superficial SAT but not VAT is associated with visceral adiposity and other features of the metabolic syndrome in women.

Barriers to initiating insulin therapy in patients with type 2 diabetes mellitus in public-sector primary health care centres in Cape Town

BACKGROUND

The majority of patients with type 2 diabetes mellitus in Cape Town who attend primary care community health centres (CHCs) have unsatisfactory glycaemic control. Insulin is rarely prescribed despite its being indicated for type 2 diabetic patients with inadequate metabolic control on maximum oral glucose-lowering agent (OGLA) therapy.

OBJECTIVE

The study examined barriers to initiating insulin therapy in poorly controlled type 2 diabetes patients on maximum OGLAs in CHCs in the Cape Town metropolis.

METHODS

Five focus group discussions and 10 in-depth semistructured individual interviews were conducted with 46 medical officers working at the CHCs. The discussions and interviews were transcribed and common themes were identified and categorised.

RESULTS

Doctor, patient, and system barriers to initiating insulin therapy were identified. Doctors' barriers include lack of knowledge, lack of experience with and use of guidelines related to insulin therapy, language barriers between doctor and patients, and fear of hypoglycaemia. Patient barriers were mistaken beliefs about insulin, non-compliance, lack of understanding of diabetes, use of traditional herbs, fear of injections, and poor socioeconomic conditions. System barriers were inadequate time, lack of continuity of care and financial constraints.

CONCLUSION

Suggestions for overcoming barriers include further education of doctors on insulin initiation and the use of standardised guidelines. In addition, a patient-centred approach with better communication between doctors and patients, which may be achieved by reorganising aspects of the health system, may improve patient knowledge, address mistaken beliefs, improve compliance and help overcome barriers. Further research is needed to investigate these recommendations and assess patients' and nurses' perceptions on initiating insulin therapy.

Barriers to initiating insulin therapy in patients with type 2 diabetes mellitus in public-sector primary health care centres in Cape Town

BACKGROUND

The majority of patients with type 2 diabetes mellitus in Cape Town who attend primary care community health centres (CHCs) have unsatisfactory glycaemic control. Insulin is rarely prescribed despite its being indicated for type 2 diabetic patients with inadequate metabolic control on maximum oral glucose-lowering agent (OGLA) therapy.

OBJECTIVE

The study examined barriers to initiating insulin therapy in poorly controlled type 2 diabetes patients on maximum OGLAs in CHCs in the Cape Town metropolis.

METHODS

Five focus group discussions and 10 in-depth semistructured individual interviews were conducted with 46 medical officers working at the CHCs. The discussions and interviews were transcribed and common themes were identified and categorised.

RESULTS

Doctor, patient, and system barriers to initiating insulin therapy were identified. Doctors' barriers include lack of knowledge, lack of experience with and use of guidelines related to insulin therapy, language barriers between doctor and patients, and fear of hypoglycaemia. Patient barriers were mistaken beliefs about insulin, non-compliance, lack of understanding of diabetes, use of traditional herbs, fear of injections, and poor socioeconomic conditions. System barriers were inadequate time, lack of continuity of care and financial constraints.

CONCLUSION

Suggestions for overcoming barriers include further education of doctors on insulin initiation and the use of standardised guidelines. In addition, a patient-centred approach with better communication between doctors and patients, which may be achieved by reorganising aspects of the health system, may improve patient knowledge, address mistaken beliefs, improve compliance and help overcome barriers. Further research is needed to investigate these recommendations and assess patients' and nurses' perceptions on initiating insulin therapy.

Adult BMI and fat distribution but not height amplify the effect of low birthweight on insulin resistance and increased blood pressure in 20-year-old South Africans

AIMS/HYPOTHESIS

We examined whether associations between low birthweight and adult chronic cardio-metabolic disease were dependent upon birthweight alone, or on interactions with BMI, fat accumulation either generally or abdominally, or attained height in young South African adults.

METHODS

Blood pressure (BP), lipids, glucose tolerance, insulin sensitivity and secretion (homeostasis model) were measured in 20-year-olds (n = 132) born at full term and with birthweights on or below the tenth centile (underweight for gestational age [UFA]) or between the 25th and 75th centiles for gestational age (appropriate weight for gestational age, [AFA]). Sex-specific median measurements of BMI, waist circumference, percentage body fat and height defined current anthropometric status, providing four groups for each measure: UFA-low or UFA-high and AFA-low or AFA-high.

RESULTS

The UFA-high BMI group was more insulin-resistant than both low BMI groups (p < 0.04), but not the AFA-high BMI group. In contrast, plasma triglycerides and systolic BP were higher in the UFA-high than in all other groups (all p < 0.04). When characterised by body fatness, both high percentage (%) body fat groups had higher fasting [insulin] than low percentage (%) body fat groups (p < 0.03), and higher [total cholesterol] and [LDL cholesterol] than the UFA-low percentage (%) body fat group (p < 0.05). The UFA-high group had higher systolic and diastolic BP than all other groups (all at least p < 0.03). A similar pattern was observed when groups were characterised by waist circumference; however, current height status had no effect.

CONCLUSIONS/INTERPRETATION

These data indicate that the "fetal origins" expression of the chronic disease phenotype is not dependent on birthweight alone, but on its interaction with subsequent fat accumulation, though not on attained height, in this cohort of young adults.

Effects of a lipase inhibitor (Orlistat) on cholecystokinin and appetite in response to a high-fat meal

OBJECTIVE

To examine the short-term effects of a lipase inhibitor (Orlistat) on physiological and behavioural measures of appetite in response to a high-fat meal.

DESIGN

Randomised, single blind, placebo-controlled, crossover trial.

SUBJECTS

A total of 19 healthy nonobese male subjects.

PROCEDURES

After an overnight fast, subjects ingested a test meal of 2940 kJ (60% fat, 30% CHO, 10% protein) with Orlistat (120 mg) or a placebo, separated by 2 weeks. Appetite, as assessed by a standard line scale, and plasma cholecystokinin (CCK) concentrations were measured prior to and every hour after the test meal for 4 h. Thereafter, subjects ingested a quantified, but self-selected portion of a standardised lunch (15% protein, 37% fat and 45% CHO), before completing a final line scale questionnaire.

RESULTS

The CCK response to the test meal was negatively correlated with BMI in both the Orlistat and placebo trials (R=-0.69 and -0.65, P<0.01). Orlistat administration did not significantly alter the CCK response to the test meal (6.30+/-3.27 vs 7.36+/-3.94 pM min, for Orlistat and placebo, P=0.193). Similarly, the line scale measures of appetite and subsequent intake (520+/-205 vs 554+/-197 g, P=0.48) were not different between the trials.

CONCLUSION

Orlistat administration did not alter short-term physiological or behavioural measures of satiety in response to a high-fat meal in healthy, nonobese subjects. The CCK response to a test meal may be partly determined by BMI.

Experiences and guidelines for footcare practices of patients with diabetes mellitus

The former Transkei is a predominantly rural region of the Eastern Cape Province. The poor infrastructure in this area results in inaccessibility of the available health services. The majority is ill equipped to deliver optimum diabetes care. There is an increase of lower limb amputations and lack of knowledge among patients with diabetes mellitus in the former Transkei. These complications can be prevented by patient education on self-management and appropriate footcare procedures. This qualitative study was conducted to explore and describe the experiences and footcare practices of diabetic patients who live in the rural areas of Transkei. A sample of 15 participants was drawn from Umtata Hospital Diabetic Clinic register through predetermined selection criteria. The sample consisted of five men aged 49-74 years, and ten women aged 30-64 years. Five patients (two men and three women) had foot ulcers or an amputation, while ten patients had no obvious foot problems. Indepth phenomenological interviews were conducted with all 15 patients. Interviews were tape recorded in Xhosa, transcribed, and translated into English for analysis. Direct observation of footcare was done with eight patients from the sample. Content analysis of the phenomenological interviews was facilitated by a protocol; and a checklist guided direct observation of footcare. A debate took place among the three coders to come to a consensus about the themes that emerged from their individual analyses. Guba's model of trustworthiness was utilised to ensure that the findings of this study reflect the truth. Ethical considerations were based on the guidelines cited by the Democratic Nursing Organisation of South Africa (1998: 2.3.1-2.3.4) and the South African Medical Research Council (1993: 32-44). Findings revealed predominantly negative experiences in the internal and external environments of the persons with diabetes mellitus; as well as poor footcare knowledge and practices. The recommendations relate to improving diabetes mellitus as well as their footcare knowledge and skills through education; promoting adherence to treatment regimens; providing emotional support; improving their self-image; changing health beliefs; improving the quality of care in public health facilities; and increasing awareness among employers of persons with diabetes mellitus.

The epidemic of obesity in South Africa: a study in a disadvantaged community

OBJECTIVE

The objective of this study was: 1) to determine the anthropometric profile of adults in Mamre, a small town in South Africa, which has a population of mixed ancestry ("colored" people of Afro-Euro-Malay-Khoisan ancestry); and 2) to determine the change in this profile between 1989 and 1996.

DESIGN

Cross-sectional surveys conducted in random samples of adults in 1989 and 1996.

PARTICIPANTS

The subjects were 684 women and 529 men in 1989, and 546 women and 430 men in 1996, aged 15 and older.

MAIN OUTCOME MEASURES

The following measurements were recorded: height, weight, and circumference of waist, hips, and mid-upper arm.

RESULTS

Based on data from the 1996 survey, 32% of women are obese (body mass index [BMI] > or = 30) at ages 25-44 years, rising to 49% at ages 45-64 years. A much lower prevalence of obesity is seen in men: 14% at ages 35-64 years. Obesity levels significantly increased in women between the two surveys (P=.015): up from 44% in 1989 to 49% in 1996 at ages 45-64 years. There was an increase in the prevalence of overweight (BMI 25-29.9) in men, though not in obesity. Mean BMI increased by about 3% in women and 2% in men between 1989 and 1996.

CONCLUSIONS

This study conducted among people of mixed ancestry living in a disadvantaged community in South Africa shows that half of middle-aged women are obese. A rising trend in BMI was seen in adults of both sexes between 1989 and 1996. This trend may be explained by factors associated with rural-urban transition, including electrification, reduced physical activity, and increasing availability of energy-dense food.

Community-based tobacco control program: the Mamre study, a demonstration project

OBJECTIVES

To assess the feasibility of a 5-year community-based tobacco control program in the community of Mamre in South Africa, while measuring the smoking and quitting rates at the beginning and end of this demonstration project.

METHODS

A tobacco intervention program was developed at low cost in collaboration with the community, and involved a wide range of activities targeting people of all ages, especially those at risk for cardiovascular disease. Community members were trained to deliver smoking cessation programs and specific advice to smokers. Cross-sectional surveys were conducted in 1989 in a random sample of 1238 people, aged 15 years and older, prior to the 5-year demonstration project, and again in 1996 among 974 people at the end of the project. Demographic data and smoking and quitting patterns were collected by interviewer-administered questionnaires. Trained field workers used standardized procedures for recording blood pressure, height, and weight.

RESULTS

The community participated with enthusiasm in the activities surrounding smoking cessation and the annual World No Smoking Day. The smoking rate decreased significantly between the two surveys (OR 1996/1989 = 0.82; 95% CI of 0.69-0.99), and the quitting rate increased significantly during the 5-year intervention period compared to the 5 years prior to the baseline survey (OR 1996/1989 = 0.74; 95% CI of 0.57-0.98). Men who participated in the program but continued to use tobacco in 1996 smoked more cigarettes than those who smoked in 1989. People who quit during the intervention period tended to be older, hypertensive, and obese; they consumed no alcohol, and noticed the health warnings posted in the community if they were older and had 10 or more years of education.

CONCLUSIONS

A low-cost community-based tobacco control program was successfully implemented in the Mamre community. The program was received enthusiastically, built tobacco cessation skills, and significantly reduced the community's smoking rate compared to that before the demonstration project.

Insulin sensitivity measured by the minimal model: no associations with fasting respiratory exchange ratio in trained athletes

The aim of this study was to examine the role of fasting insulin concentrations and tissue insulin sensitivity on whole-body substrate oxidation in 61 well-trained subjects. Subjects underwent a frequently sampled intravenous glucose tolerance test (FSIVGT) after a 10- to 12-hour overnight fast. Minimal model analysis was used to determine insulin sensitivity (S(i)). A week later, fasting (10- to 12-hour) respiratory exchange ratio (RER) was measured at rest and during exercise at 25%, 50%, and 70% of peak power output (W(peak)). Prior to these measurements, training volume, dietary intake, and muscle fiber composition, substrate concentrations, and enzyme activities were determined. The average fasting plasma insulin concentration was 7.3 +/- 2.4 microU/mL (4.0 to 10.5 microU/mL), and the mean S(i) was 14.0 +/- 6.1 x (10(-4) min(-1) x microU(-1) x mL(-1)) (2.6 to 26.3 x 10(-4) min(-1) x microU(-1) x mL(-1)). There was no significant correlation between fasting plasma insulin concentration and S(i) (r = -.14, P =.336) or between these measurements and fasting RER, measured at rest and during exercise at 25%, 50%, and 70% W(peak). Only VO(2max) and the proportion of type 1 muscle fibers were significantly correlated with S(i) (r =.30, P =.045 and r =.34, P =.026, respectively), and waist-to-hip ratio (WHR) was significantly correlated with fasting plasma insulin concentration (r =.35, P =.006). In conclusion, S(i) and fasting plasma insulin concentration were not associated with fasting RER at rest and during exercise of increasing intensity in trained athletes who have high S(i).

Waist circumference predicts clustering of cardiovascular risk factors in older South Africans

OBJECTIVE AND DESIGN

A cross-sectional analytical study to determine the cardiovascular risk factor profile of older residents of fishing villages on the West Coast of South Africa, and to determine which anthropometric measures are associated with risk factors.

SUBJECTS

A convenient community-based sample of 152 subjects of mixed ancestry aged 55 years and over was recruited door-to-door using an address list of age-eligible subjects provided by the local public health care clinics.

METHODS

Cardiovascular relationships were investigated between (i) number of risk factors (hypertension, hypercholesterolaemia, diabetes) and body mass index (BMI), waist-to-hip ratio (WHR), and waist circumference; and (ii) continuous cardiovascular risk factor variables and physical activity, smoking, dietary intake, and 24-hour urinary sodium and potassium concentrations.

RESULTS

The prevalence of hypertension ( > or =160/95 mmHg) was 74.3% (95% CI: 67.2 - 81.4%). Neither 24-hour urinary sodium nor potassium concentrations was associated with blood pressure (BP). Past, but not present, moderate-intensity physical activity, particularly that associated with occupation, was negatively associated with systolic BP (r = -0.24, P < 0.05). The prevalence of diabetes and hypercholesterolaemia (serum cholesterol > or = 6.5 mmol/l) was 24.6% (95% CI: 17.2 - 32%) and 40% (95% CI: 31.8 - 48.2%), respectively. The percentage of subjects with 0, 1, or 2 or more cardiovascular risk factors was 13.4%, 44.1% and 42.5%, respectively. Subjects with a waist circumference > or = 92 cm had a significantly higher number of cardiovascular risk factors than those with a waist circumference < 92 cm ( chi(2) = 9.29, P < 0.01), and this association remained significant even after controlling for age, sex and smoking (P < 0.05). Neither BMI tertiles according to sex, nor a BMI cut-point > or =30, was significantly associated with a clustering of risk factors.

CONCLUSION

In a sample of older South Africans of mixed ancestry at high risk of cardiovascular disease, waist circumference measuring > or = 92 cm predicts clustering of risks factors, independently of BMI. This simple, population-specific reference value may provide a useful screening tool to identify at-risk individuals for targeted prevention for coronary heart disease and associated metabolic disorders.

Contribution of growth hormone-releasing hormone and somatostatin to decreased growth hormone secretion in elderly men

OBJECTIVE

The pathophysiology of the decline in circulating growth hormone (GH) concentrations that may occur with ageing remains elusive. We have investigated the potential contributions of decreased endogenous GH-releasing hormone (GHRH) and increased somatostatin secretion to this phenomenon.

DESIGN AND METHODS

The strategy used was to stimulate GH secretion in 8 young (20-24 years old, body mass index (BMI) 22.8 +/- 2.8 kg/m2) and 8 elderly (68-82 years old, BMI 23.4 +/- 1.6 kg/m2) male subjects on separate occasions by means of: (i) intravenous bolus 0.5 microgram/kg D-Ala2 GHRH(1-29)-NH2 alone; (ii) 0.5 microgram/kg GHRH after pre-treatment with two oral doses of 50 mg atenolol (to inhibit somatostatin secretion); (iii) 1.25 mg oral bromocriptine alone (to increase endogenous GHRH and/or inhibit somatostatin); (iv) 50 mg oral atenolol plus 1.25 mg oral bromocriptine; and (v) 0.5 microgram/kg GHRH after pre-treatment with 1.25 mg oral bromocriptine.

RESULTS

The elderly men had a significantly lower peak and area under curve (AUC) GH response to intravenous GHRH when compared with 8 young men (peak 3.1 +/- 1.0 ng/ml v. 21.6 +/- 5.0 ng/ml, AUC 205 +/- 56 ng/ml/min v. 1,315 +/- 295 ng/ml/min, P < 0.05). Pre-treatment with atenolol before GHRH administration produced no significant increase in peak and AUC GH response in both groups, which remained lower in the elderly men than in their young counterparts (peak 5.5 +/- 1.8 ng/ml v. 29.3 +/- 7.0 ng/ml, AUC 327 +/- 90 ng/ml/min v. 2,017 +/- 590 ng/ml/min, P < 0.05). Bromocriptine alone did not cause a significant rise in GH concentration in either elderly or young subjects (peak 3.1 +/- 1.1 v. 8.8 +/- 3.2 ng/ml, P > 0.05). When atenolol was administered before bromocriptine, both groups responded but the elderly subjects had a significantly greater peak and AUC response (peak 3.6 +/- 0.7 v. 10.7 +/- 2.1 ng/ml; AUC 191 +/- 39 v. 533 +/- 125 ng/ml/min, P < 0.05). Bromocriptine given before GHRH failed to potentiate GHRH action on GH release in either group. Of 5 elderly men who underwent further evaluation of GH secretory ability, 2 subjects had GH levels > 10 ng/ml, either basally or after intravenous GHRH. The remaining 3 had an initially impaired GH response to bolus intravenous GHRH. After 100 micrograms GHRH subcutaneously twice daily for up to 2 weeks the GH responses to intravenous bolus GHRH (0.5 microgram/kg) were reassessed. One exhibited a normal response (> 10 ng/ml) after 1 week of daily GHRH treatment, another had a near-normal response after 2 weeks (9.7 ng/ml), while the third still had an impaired response by the end of the 2-week treatment period (3.2 ng/ml).

CONCLUSIONS

The restoration of endogenous GH secretion in these elderly subjects by means of GHRH priming, and the failure of manipulation of somatostatinergic tone to restore a normal GH response to GHRH suggests that somatotroph atrophy due to a reduction in endogenous GHRH secretion is the principal cause of the diminished GH secretion with ageing.

Acromegaly in the developing world--a 20-year teaching hospital experience

A retrospective analysis was conducted to examine the long-term outcome of surgery, by a single pituitary surgeon and radiotherapy for acromegaly at Groote Schuur Hospital, Cape Town, using modern criteria for the definition of cure. Seventy-two patients (F/M ratio 1.3:1), aged 16-74 years, were eligible for inclusion. The mean follow-up period was 8.3 years. Macroadenomas were present in 79%, microadenomas in 15% and tumour size was not documented in 6%. Pretreatment GH levels were, > or = 40 m U/l in 56 patients. Postoperatively, 21% of patients were cured, 40% controlled and 40% had hypopituitarism. After radiotherapy (mean follow-up 8.7 years) 43% were cured, 66% controlled and 78% had hypopituitarism. At follow-up 37% of patients traced had died. The most common cause of death was vascular disease. The poor surgical results may be attributed to late presentation in the developing world setting, as evidenced by tumour size and invasiveness, and the degree of GH elevation. Emphasis on early diagnosis of non-invasive tumours is necessary to improve the cure rate and reduce mortality,

Ambivalence of primary health care professionals towards the South African guidelines for hypertension and diabetes

BACKGROUND

Consensus-derived guidelines for hypertension and diabetes management were introduced by the National Department of Health to improve quality of care. However, the incorporation of guidelines into clinical practice is largely dependent on the attitudes of health professionals.

OBJECTIVE

To audit the responses and examine the attitudes of health professionals in primary care towards the diabetes and hypertension care guidelines.

DESIGN

Qualitative focus group, in-depth discussions and clinic observations.

SETTING

Four community health centres (CHCs) in the Western Cape.

SUBJECTS

Fifteen doctors and 10 professional nurses.

METHODS

The responses of health professionals to the guidelines were audited. Their attitudes were evaluated at a single pilot CHC using focus group discussions and in-depth interviews. Semi-structured interviews based on these themes were conducted at 3 other CHCs. Clinic consultations were observed to validate the responses.

RESULTS

The guidelines were not systematically implemented at local CHCs and individual doctors consulted the guidelines infrequently. Several themes were identified as barriers to the application of the guidelines, including the consultation process by which the guidelines were developed, time constraints, scepticism about durability of the guidelines, conflict with local practices, health system problems, and patient beliefs.

CONCLUSION

The usefulness of passive dissemination of guidelines to health professionals in primary care should be reviewed as several attitudinal barriers to implementation may exist. Guidelines may be adopted more readily if these barriers are addressed.

Impaired glucose tolerance and elevated blood pressure in low birth weight, nonobese, young south african adults: early programming of cortisol axis

Low birth weight is associated with increased cardiovascular and metabolic disorders in adult life, although the mechanisms of this effect remain uncertain. There is one report of increased morning plasma cortisol levels in an elderly low birth weight cohort, but whether this is primary or secondary to other aspects of the phenotype is unclear. We investigated the association between low birth weight and glucose intolerance, blood pressure, and dyslipidemia in young, nonobese adults from a community undergoing the health transition with a high prevalence of both noncommunicable diseases and low birth weight. Additionally, we investigated whether altered basal and stimulated cortisol levels as a marker of hypothalamic-pituitary-adrenal responsiveness or cortisol metabolism were associated with low birth weight in these young adults. Twenty-year-old, historically disadvantaged, urbanized South Africans (n = 137) with birth weights either below the 10th percentile [underweight for age (UFA)] or between the 25th and 75th percentiles [appropriate for gestational age (AFA)] had anthropometry, blood pressure, lipid levels, and glucose tolerance measured. In a subset (n = 62), 0900 h plasma cortisol concentrations, cortisol responses to 1 microg ACTH, and urinary glucocorticoid metabolites were measured. The mothers of UFA infants were themselves lighter and had a lower body mass index (P: = 0. 0016). At age 20 yr, although the UFA group was still smaller and lighter, with a lower body mass index, they had higher fasting plasma glucose levels (P: = 0.047), and a greater proportion demonstrated glucose intolerance (11.9% vs. 0%; P: < 0.01). The UFA group also had higher systolic [UFA, 126.0 +/- 13.3 (+/-SD); AFA, 122.0 +/- 11.7 mm Hg; P: = 0.007] and diastolic (72.3 +/- 8.4 vs. 69. 5 +/- 8.7 mm Hg; P: = 0.02) blood pressures, after covarying for current weight and gender. Plasma cortisol levels determined at 0900 h were higher in the UFA group (484.9 +/- 166.3 vs. 418.6 +/- 160.6 nmol/L) and showed a greater plasma cortisol response to low dose ACTH stimulation (area under the curve for cortisol: UFA, 77,238 +/- 19,511; AFA, 66,597 +/- 16,064 nmol/L.min; P: = 0.04). In conclusion, the link between low birth weight and adult glucose intolerance and blood pressure elevation occurs in young adults in a high risk, disadvantaged population despite a lack of full catch-up growth. Moreover, cortisol axis activation is an early feature in the process linking low birth weight with adult cardiovascular and metabolic disease and is not dependent upon adult obesity or full catch-up growth, at least in this population undergoing the health transition.

Primary hypoadrenalism assessed by the 1 microg ACTH test in hospitalized patients with active pulmonary tuberculosis

Primary hypoadrenalism, assessed by 250 microg ACTH stimulation, is uncommon in patients with active pulmonary tuberculosis (PTB). Since 1 microg ACTH produces an equivalent +30 min cortisol response to 250 microg in control subjects, the 250 microg dose is supraphysiological and may lack sensitivity for the diagnosis of hypoadrenalism. Furthermore, the impact of coexistent HIV infection on the prevalence of primary hypoadrenalism in PTB is uncertain. We thus determined the cortisol response to an intravenous bolus of 1 microg ACTH in 21 controls, 18 HIV-positive (BMI 19.5+/-0.9 kg/m(2), albumin 24+/-1.4 g/l, CD4 count 192+/-47/mm(3)) and 22 HIV-negative (BMI 19.3+/-0.8 kg/m(2), albumin 29+/-1 g/l, CD4 count 652+/-76/mm(3)) patients with active PTB. The mean basal cortisol was greater in patients than in controls (559 vs. 373 nmol/l, p=0. 0009). The mean cortisol after 1 microg ACTH stimulation did not, however, differ significantly when comparing either patients and controls or patients who were HIV-positive and -negative (p>0.05). Using the minimum +30 min cortisol derived from the 21 controls as a marker of normal adrenal function (414 nmol/l), a single patient was classified as hypoadrenal. In conclusion, primary hypoadrenalism, as assessed by the 1 microg ACTH test, is uncommon in a cohort of ill, hospitalized patients with active PTB, irrespective of HIV status.

Maternal diabetes and neonatal outcome

The new definitions and classification of diabetes is discussed. An electronic literature search was done especially for randomized trials in management of maternal diabetes. However, because of the paucity of such trials the modern management we propose is still based on evaluative and retrospective evidence. Problems of type 2 diabetes specifically in the developing world are highlighted. Although the goals of the St Vincent declaration are attainable; in a practical setting (even in excellent centres) we fall far short of achieving perinatal mortality and fetal anomaly rates equivalent to the non-diabetic pregnant population. This is mainly due to lack of excellent pre-conceptional care for the future diabetic mother.

Cardiovascular disease risk factors in 5-year-old urban South African children--the Birth to Ten Study

BACKGROUND

A birth cohort study, the Birth to Ten (BTT) study, commenced in the greater Johannesburg/Soweto metropole in South Africa in 1990. The overall BTT project collected antenatal, birth and early development information on these children as well as information that could help identify factors related to the emergence of risk of cardiovascular diseases (CVDs) in children.

OBJECTIVE

To determine CVD risk profiles and their determinants in 5-year-old children living in an urban environment in South Africa.

METHODS

Demographic and birth characteristics were collected on a sample of 964 5-year-olds whose parents agreed for blood samples to be taken from their children. The children's height and weight were measured using standardised procedures; blood pressure (BP) was measured with a Dinamap Vital Signs Monitor, and a non-fasting blood sample was drawn for lipid determinations. Information on exposure to tobacco smoke and additional health-related data were obtained by interview.

RESULTS

No differences were found between the birth weight and gestational age of the 5-year-old CVD participants and the remainder of the children studied at birth. The systolic BP was significantly different between ethnic groups, with the BP of the black children significantly higher than that of the Indian and white children, while the diastolic BP of black children was also the highest. White children had the highest mean total cholesterol (TC) and low-density lipoprotein cholesterol (LDLC) levels, significantly higher than those in the black community. The coloured children's TC level was also significantly lower than that of the whites, while the LDLC level of the Indian children was significantly higher than that of the blacks. Overall, 64% of the children were exposed to environmental tobacco smoke (ETS), with the white group having the lowest rate (45% exposed to ETS). The coloured children were most frequently exposed to ETS, with 40.6% having primary caregivers who smoked; of these children 42% lived in homes with two or more smokers.

CONCLUSIONS

Tobacco control legislation will protect South Africans against tobacco sales promotions. This will be the first step towards increasing the priority of chronic disease prevention, health promotion and appropriate care for chronic diseases and their risk factors on the South African health policy agenda. The groups of children that were studied carried differing but significant levels of CVD risk. This suggests that the promotion of a healthy lifestyle should start in childhood, and should target the risk factors found in each group.

Application of the new ADA criteria for the diagnosis of diabetes to population studies in sub-Saharan Africa. American diabetes association

AIMS

To examine the implications for epidemiological studies of the American Diabetes Association (ADA) recommendation that the fasting blood glucose at a lowered level becomes the main diagnostic test for diabetes on cross-sectional-based data from sub-Saharan Africa.

METHODS

Data from 11 surveys conducted in rural, peri-urban and urban Cameroon (n = 1804), South Africa (n = 3799) and Tanzania (n = 10013) which measured fasting (ADA criteria) and 2-h blood glucose concentrations during a standard 75 g OGTT (old WHO criteria) were analysed.

RESULTS

The prevalence of diabetes was higher in eight of the 11 surveys when applying the new ADA compared to the old WHO criteria. With the exception of one population (Mara, Tanzania) the absolute difference in prevalence between the two classifications tended to be small (< 2%). There was considerable variation in the categorization of individuals using the ADA and old WHO criteria. The level of agreement between the two ranged from fair to good (Kappa statistic 0.17-0.86). The prevalence of impaired fasting glycaemia (IFG) was lower than that of impaired glucose tolerance (IGT) in 10 of the surveys and the agreement between the two was fair, < or = 0.26 in all the surveys.

CONCLUSIONS

Although the use of the new ADA fasting criteria for prevalence surveys is an attractive and practical option, particularly in Africa, further information is required on the characteristics and prognosis of individuals classified as IFG or diabetic by the fasting criteria, prior to wide adoption of the ADA criteria. Ideally measurement of both fasting and two low glucose concentrations should remain the standard for epidemiological studies.

A structured record to implement the national guidelines for diabetes and hypertension care

BACKGROUND

Guidelines to improve standards of care for hypertension and diabetes were disseminated by the National Department of Health in 1996 but have generally not been implemented by health professional in local primary care. A strategy for the adoption and implementation of the Guidelines was developed in collaboration with health professionals in primary care.

OBJECTIVES

The development of a structured record, with prompts for the management of diabetes and hypertension according to the Guidelines.

SETTING

Three community health centres (CHCs) in the Western Cape.

PARTICIPANTS

Doctors and nurses managing patients with diabetes and hypertension.

METHODS

A draft of the structured record was developed at a single-pilot CHC in the Western Cape. Focus group discussions established the core requirements for a structured record. Process, result and structural indicators in line with the national Guidelines were considered for inclusion in the draft record. This draft record was then piloted at two other CHCs. Comments from semi-structured interviews and pre- and post-test evaluation questionnaires were used to compile the final instrument.

RESULTS

Eleven doctors and 8 nurses participated in the development of the final instrument. Important considerations in the design were a single-page, user-friendly format, tick-boxes to reduce writing, prompts, provision for sequential recording, target setting, and compatibility with the Guidelines. The final instrument was piloted and elicited a favourable overall response.

CONCLUSION

The structured record simplifies the application of the Guidelines and the systematic recording of processes of care. The effectiveness of the Guidelines will be evaluated further in a randomised control trial using the structured record.

Modifiable risk factors for Type 2 diabetes mellitus in a peri-urban community in South Africa

AIMS

To investigate the prevalence of Type 2 diabetes mellitus (DM) and its risk factors in a working class peri-urban community in South Africa.

METHODS

A cross-sectional descriptive study was conducted in 1996, where all persons aged 15 years and older, who were resident in randomly selected houses in Mamre, 55 km from the centre of Cape Town, were sampled. Subjects underwent a 75-g oral glucose tolerance test. Socio-demographic and anthropometric data were obtained and physical activity was assessed using a 7-day activity recall questionnaire. The 1985 WHO criteria were used to define diabetes.

RESULTS

The response rate was 64.5% (n = 974). The participants comprised 56% women, 44% men, mean age 37.6 (range 15-86) years. The crude prevalence of Type 2 DM was 7.1% and impaired glucose tolerance (IGT) 8.0%. The age-adjusted prevalence of Type 2 DM was 10.8% (95% confidence interval (CI) 8.2-13.5%) and IGT 10.2% (95% CI 7.7-12.8%). Regression analysis indicated that age (risk ratio (RR) 7.40, 95% CI 3.45-15.86), waist circumference (RR 4.53, 95% CI 2.04-10.05), low total energy expenditure (RR 1.75, 95% CI 1.07-2.56) and family history of diabetes (RR 2.31, 95% CI 1.42-3.77) were independent risk factors for Type 2 DM, while sex, obesity and regular alcohol consumption were not.

CONCLUSIONS

This previously unstudied community has an intermediate prevalence on the international scale of Type 2 DM, which is linked to potentially modifiable risk factors.

An inverse relation between blood pressure and birth weight among 5 year old children from Soweto, South Africa

STUDY OBJECTIVE

To examine the relation between birth weight and blood pressure at 5 years in a cohort of South African children.

DESIGN

Prospective cohort study.

PARTICIPANTS

849 five year old children.

SETTING

Soweto, a sprawling urban area close to Johannesburg, South Africa, which was a designated residential area for people classified as "black" under apartheid legislation.

MAIN RESULTS

Systolic blood pressure at 5 years was inversely related to birthweight (r = -0.05, p = 0.0007), independent of current weight, height, gestational age, maternal age or socioeconomic status at 5 years. There was no relation between birth weight and diastolic blood pressure. After adjusting for current weight and height, there was a mean decline in systolic blood pressure of 3.4 mm Hg (95% confidence intervals 1.4, 5.3 mm Hg) for every 1000 g increase in birth weight.

CONCLUSIONS

These data from a disadvantaged urbanised community in Southern Africa extend the reported observations of an inverse relation between birth weight and systolic blood pressure. The study adds to the evidence that influences in fetal life and early childhood influence systolic blood pressure. Further research is required to assess whether efforts to reduce the incidence of low birthweight babies will attenuate the prevalence of hypertension in future generations.