N S Levitt

University of Cape Town, Kaapstad, Western Cape, South Africa

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Publications (159)511.19 Total impact

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    ABSTRACT: To determine the metabolic syndrome prevalence by the 2009 harmonised criteria in 25-74-year-old urban Africans in Cape Town.
    European Journal of Preventive Cardiology 09/2014; · 3.90 Impact Factor
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    ABSTRACT: : Globally, the HIV epidemic is evolving. Life expectancy for HIV-infected individuals has been extended because of more effective and more widely available antiretroviral therapy. As a result, chronic noncommunicable diseases (NCDs) have become important comorbid conditions. In particular, HIV-infected persons are increasingly at risk of developing metabolic (diabetes, dyslipidemias), body composition (lipodystrophy, overweight/obesity) and bone mineral density abnormalities. We have summarized the published epidemiological and clinical literature regarding these HIV-NCD comorbidities in low- and middle-income countries (LMICs). We found important gaps in knowledge. Specifically, there are few studies that use standardized methods and metrics; consequently, prevalence or incidence data are not comparable. There are very little or no data regarding the effectiveness or cost-effectiveness of clinical monitoring or therapeutic interventions for metabolic disorders in HIV-infected individuals. Also, although NCDs continue to grow in the HIV-negative population of most LMICs, there are few data comparing the incidence of NCD comorbidities between HIV-infected and HIV-negative populations. To address these gaps, we describe potential research and capacity development priorities for the future.
    Journal of acquired immune deficiency syndromes (1999). 09/2014; 67 Suppl 1:S27-39.
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    ABSTRACT: Health related quality of life (HRQoL) is an important outcome helping to understand the impact of antiretroviral therapy (ART). We examined and compared the HRQoL in relation to ART status among HIV-infected patients in a public sector service in Cape Town, South Africa. In addition, we aimed to examine the relationship between ART status and HRQoL according to CD4 count strata.
    BMC Public Health 07/2014; 14(1):676. · 2.08 Impact Factor
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    ABSTRACT: Human immunodeficiency virus (HIV) and antiretroviral therapy (ART) are associated with renal disease and increased cardiovascular risk. The relationship between HIV and ambulatory blood pressure (ABP) non-dipping status, a risk factor for cardiovascular events and targetorgan damage, has never been assessed in South Africa. Study objectives were to establish the prevalence of chronic kidney disease, and assess the ABP profile in asymptomatic HIV-positive clinic out-patients.
    Cardiovascular journal of Africa. 07/2014; 25(4):153-157.
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    ABSTRACT: Our understanding of genome biology, genomics, and disease, and even hu-man history, has advanced tremen-dously with the completion of the Human Genome Project. Technologi-cal advances coupled with significant cost reductions in genomic research have yielded novel insights into disease etiol-ogy, diagnosis, and therapy for some of the world's most intractable and devastat-ing diseases—including ma-laria, HIV/AIDS, tuberculosis, cancer, and diabetes. Yet, de-spite the burden of infectious diseases and, more recently, noncommunicable diseases (NCDs) in Africa, Africans have only par-ticipated minimally in genomics research. Of the thousands of genome-wide association studies (GWASs) that have been conducted globally, only seven (for HIV susceptibility, malaria, tuberculosis, and podoconiosis) have been conducted exclusively on Afri-can participants; four others (for prostate cancer, obsessive compulsive disorder, and anthropometry) included some African participants (www.genome.gov/gwastudies/). As discussed in 2011 (www.h3africa.org), if the dearth of genomics research involving Africans persists, the potential health and economic benefits emanating from genomic science may elude an entire continent. The lack of large-scale genomics studies in Africa is the result of many deep-seated issues, including a shortage of African scien-tists with genomic research expertise, lack of biomedical research infrastructure, lim-ited computational expertise and resources, lack of adequate support for biomedical research by African governments, and the participation of many African scientists in collaborative research at no more than the level of sample collection. Overcoming these limitations will, in part, depend on African Enabling the genomic revolution in Africa By The H3Africa Consortium * H3Africa is developing capacity for health-related genomics research in Africa Yet, roughly a decade ago, newly pro-posed DNA-based taxonomy (11) promised to solve the species debate. A Barcode of Life Data Systems (BOLD) (12) quickly emerged, seeking to provide a reliable, cost-effective solution to the problem of species identification (12) and a standard screening threshold of sequence differ-ence (10× average intraspecific difference) to speed the discovery of new animal spe-cies (13). Sometimes considered a "carica-ture of real taxonomy" (14), this approach failed to identify, perhaps not surprisingly, two American crow species and a number of members of the herring gull Larus ar-gentatus species assemblage above the set threshold (13). Furthermore, despite past (3) and present (6) sequencing projects, carrion crows and hooded crows can also not be differentiated from one another by means of DNA-barcode approaches. By contrast, Poelstra et al. show that much more DNA sequencing data are needed, combined with RNA expression data, to reconstruct the evolution of a reproductive barrier that culminated in the speciation of these two crow taxa. Armed with this new very detailed genetic informa-tion, it is clear that none of the currently formulated species concepts fully apply to these two crow taxa (unless one is willing relax some stringency in the various definitions). In-deed, the genomes of German carrion crows are much more similar to those of hooded crows than to Spanish car-rion crows. Put simply, apart from the few carrion crow type "speciation islands," German carrion crows could be con-sidered to represent hooded crows with a black (carrion crow) phenotype. There is a clear need for ad-ditional population genomic studies using a more dense sampling, especially among the fully black carrion crows, before the complexity of repro-ductive isolation and speciation among these two taxa can be fully understood. The specia-tion genomics strategy already proved itself in unraveling the complexities of mimicry among many Heliconius butterfly taxa (7) and, as in the study of Poelstra et al., stresses the im-portance of using RNA-based information in addition to DNA. Only time will tell if, and when, German carrion crows will adopt the "hooded phenotype," a fate that seems un-avoidable. Until then, we can only applaud these crows for defeating Linnaeus's curse.
    Science /AAAS. 06/2014; 344(6190):1346-1348.
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    ABSTRACT: The burden of non-communicable diseases is rising, particularly in low and middle-income countries undergoing rapid epidemiological transition. In sub-Saharan Africa, this is occurring against a background of infectious chronic disease epidemics, particularly HIV and tuberculosis. Consequently, multi-morbidity, the co-existence of more than one chronic condition in one person, is increasing; in particular multimorbidity due to comorbid non-communicable and infectious chronic diseases (CNCICD). Such complex multimorbidity is a major challenge to existing models of healthcare delivery and there is a need to ensure integrated care across disease pathways and across primary and secondary care.
    BMC Public Health 06/2014; 14(1):575. · 2.08 Impact Factor
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    ABSTRACT: 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 (H6PDH), and glucocorticoid receptor-α (GRα), as well as genes involved in adipogenesis and inflammation were measured in abdominal deep SAT (DSAT), superficial SAT (SSAT), 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.ResultsAlthough 11HSD1 activity and mRNA did not differ by ethnicity, GRα mRNA levels were significantly lower in SAT of black compared to 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 black women.Conclusions In black SA women, down-regulation of GRα mRNA levels with obesity and reduced insulin sensitivity, possibly via increased SAT inflammation, is associated with reduced VAT accumulation.International Journal of Obesity accepted article preview online, 23 May 2014; doi:10.1038/ijo.2014.94.
    International journal of obesity (2005) 05/2014; · 5.22 Impact Factor
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    ABSTRACT: 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/m2 vs. 24.7±3.4 kg/m2 (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.
    Hormone and Metabolic Research 05/2014; · 2.15 Impact Factor
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    ABSTRACT: Microvascular dysfunction precedes the clinical manifestations of cardiovascular disease (CVD). Given the ethnic disparities in CVD, we aimed to investigate ethnic differences in microvascular endothelial function in a group of young (18–33 yrs), apparently healthy persons (n = 33, 9 Black African, 12 Mixed Ancestry, 12 Caucasian). Microvascular endothelial-dependent and -independent function were assessed by laser Doppler imagery and iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP), respectively, adjusting for skin resistance (SR). Microvascular reactivity was expressed as maximum absolute perfusion,% change from baseline, and area under the curve (AUC). SR was significantly lower in the Caucasian group in response to ACh (Caucasian: mean 0.16 ± 0.03 vs. Black: 0.21 ± 0.04 and Mixed Ancestry: 0.20 ± 0.02 ohms, P < 0.01) and SNP (Caucasian: 0.08 ± 0.01 vs. Black: 0.11 ± 0.02 and Mixed Ancestry 0.12 ± 0.01 ohms, P < 0.01). Microvascular function in response to ACh was significantly higher in the Caucasian group, compared to the other two groups, however, after adjusting for SR these differences were no longer significant. Conversely, microvascular SNP response remained significantly higher in the Caucasian group, even after adjusting for SR (P < 0.01). Diastolic blood pressure was inversely associated with the AUC of ACh (r = −0.4) and all SNP responses (r = −0.3 to −0.6). SR was inversely associated with AUC and maximum absolute response ACh (r = −0.59 and −0.64, respectively) and all SNP responses (r = −0.37 to −0.79). Ethnic differences in endothelial-independent microvascular function may contribute to ethnic disparities in CVD. Moreover, SR plays a significant role in the interpretation of microvascular response to iontophoresis outcomes in a multi-ethnic group.This article is protected by copyright. All rights reserved
    Experimental physiology 05/2014; · 3.17 Impact Factor
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    ABSTRACT: To examine the prevalence and determinants of tobacco use in the 25-74-year-old urban Black population of Cape Town and to examine the changes between 1990 and 2008/09 in the 25-64-year-old sample. In 2008/09 (n = 1,099), a representative cross-sectional sample was randomly selected from the same townships sampled in 1990 (n = 986). Sociodemographic characteristics, tobacco use by the World Health Organization (WHO) STEP-wise questionnaire, and psychosocial stress, including sense of coherence (SOC), locus of control, and adverse life events, were determined. Survey logistic regression analysis assessed the determinants of smoking ≥1 cigarette/day. There were 392 men and 707 women. Age-standardized prevalence of smoking ≥1 cigarette/day was 48.5% (95% confidence interval [CI] = 43.0-54.0) in men and 7.8% (95% CI = 5.8-10.5) in women (p < .001). Prevalence in men was lower in 2008/09 (51.0%, 95% CI = 45.2-56.7) compared with 1990 (59.7%, 95% CI = 53.8-65.4) but unchanged in women (2008/09: 8.0%, 95% CI = 5.9-10.7; 1990: 8.4%, 95% CI = 6.0-11.8). In the logistic model for men, smoking was associated with younger age (p = .005) and being poor (p = .024). In women, spending more than half their lives in the city (p < .001), being poor (p = .002), and coping poorly with stress (defined by lower SOC; OR: 1.04, 95% CI = 1.01-1.08; p = .035) were associated with smoking. Increasing number of adverse events, which replaced SOC in the same models, was significant for women (OR: 1.10, 95% CI = 1.01-1.21; p = .047) but not for men. Education level, employment status, and housing quality were not relevant for men or women. The high smoking prevalence in men and unchanged rate in women require additional interventions to curtail this behavior.
    Nicotine & Tobacco Research 04/2014; · 2.48 Impact Factor
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    ABSTRACT: Abstract Background: The association between insulin resistance and microvascular dysfunction is well established in obese individuals with type 2 diabetes. It is unclear whether this relationship is dependent on obesity and body fat in insulin-resistant persons. This study investigated acetylcholine (ACh)-induced microvascular reactivity in apparently healthy women (n=37, 20-45 years), with and without insulin resistance. Methods: Body fat mass (dual X-ray absorptiometry), waist circumference (WC), blood pressure, fasting glucose, insulin, and free fatty acid concentrations were measured. Insulin resistance was estimated using homeostasis model assessment of insulin resistance (HOMA-IR), and subjects were divided into insulin-resistant (IR, n=16) and insulin-sensitive (IS, n=21) groups. ACh-induced forearm microvascular reactivity was measured by laser Doppler imagery using iontophoresis of ACh and compared between groups adjusting for WC and skin resistance (SR). Results: The IR group had a higher body mass index (BMI) (30.7±6.4 vs. 22.9±7.3 kg/m(2), P<0.01), fat mass (34.7±11.9 vs. 19.7±9.6 kg, P<0.01), WC (89.9±13.6 vs. 74.4±9.7 cm, P<0.01), and a lower SR (0.24±0.08 vs. 0.32±0.08 Ω, P<0.05) than the IS group. Microvascular reactivity, expressed as percentage increase in perfusion from baseline, was significantly lower in IR subjects after adjusting for differences in WC and SR (420.9±166.5 vs. 511.6±214.8%, P<0.05). There were associations between microvascular reactivity and SR (r=-0.34, P<0.05) and systolic blood pressure (r=-0.36, P<0.05), but not BMI, body fat mass, WC, or HOMA-IR. Conclusion: ACh-induced microvascular reactivity was different between IR and IS apparently healthy, nondiabetic women once differences in WC and SR were accounted for.
    Metabolic syndrome and related disorders 01/2014;
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    ABSTRACT: Interventions to support people with hypertension in attending clinics and taking their medication have potential to improve outcomes, but delivery on a wide scale and at low cost is challenging. Some trials evaluating clinical interventions using short message service (SMS) text-messaging systems have shown important outcomes, although evidence is limited. We have developed a novel SMS system integrated with clinical care for use by people with hypertension in a low-resource setting. We aim to test the efficacy of the system in improving blood pressure control and treatment adherence compared to usual care.Methods/design: The SMS Text-message Adherence suppoRt trial (StAR) is a pragmatic individually randomised three-arm parallel group trial in adults treated for hypertension at a single primary care centre in Cape Town, South Africa. The intervention is a structured programme of clinic appointment, medication pick-up reminders, medication adherence support and hypertension-related education delivered remotely using an automated system with either informational or interactive SMS text-messages. Usual care is supplemented by infrequent non-hypertension related SMS text-messages. Participants are 1:1:1 individually randomised, to usual care or to one of the two active interventions using minimisation to dynamically adjust for gender, age, baseline systolic blood pressure, years with hypertension, and previous clinic attendance. The primary outcome is the change in mean systolic blood pressure at 12-month follow-up from baseline measured with research staff blinded to trial allocation. Secondary outcomes include the proportion of patients with 80% or more of days medication available, proportion of participants achieving a systolic blood pressure less than 140 mmHg and a diastolic blood pressure less than 90 mmHg, hospital admissions, health status, retention in clinical care, satisfaction with treatment and care, and patient related quality of life. Anonymised demographic data are collected on non-participants. The StAR trial uses a novel, low cost system based on widely available mobile phone technology to deliver the SMS-based intervention, manage communication with patients, and measure clinically relevant outcomes. The results will inform implementation and wider use of mobile phone based interventions for health care delivery in a low-resource setting.Trial registration number: NCT02019823.
    BMC Public Health 01/2014; 14(1):28. · 2.08 Impact Factor
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    ABSTRACT: To determine the prevalence and determinants of problematic alcohol use (CAGE ≥2) in 25-74-year-old black population in Cape Town in 2008/2009 and examine the changes in self-reported alcohol consumption between 1990 and 2008/2009 in 25-64-year-olds. In 2008/2009, a representative cross-sectional sample, stratified for age and sex, was randomly selected from the same townships sampled in 1990. Socio-demographic characteristics, the ability to cope with psychosocial stress (sense of coherence) and adverse life events were determined. Ordinal logistic regression analysis assessed the determinants of problem drinking. There were 1099 participants, 392 men and 707 women, in 2008/2009. Prevalence of alcohol consumption in 2008/2009 (men: 68.5%, 95% CI 62.7 to 73.7; women: 27.4%, 95% CI 23.7 to 31.5) was higher than in 1990 (men: 56.7%, women: 15.1%). Prevalence of problem drinking was significantly higher in men (49.7%, 95% CI 44.6 to 54.9) than in women (18.1% 95% CI 15.3 to 21.2) (p<0.001). In men, greater alcohol use was associated with >7 years of education (p=0.012), being unemployed compared with employed (p=0.008) and coping poorly with stress (OR 1.02, 95% CI 1.01 to 1.05, p=0.042), and in women with spending more than half their life in the city (p<0.001) and coping poorly with stress (OR 1.02, 95% CI 1.01 to 1.04, p=0.039). The odds for greater alcohol use with increasing number of adverse life events, after adjusting for the other factors, was significant in men (OR 1.11, 95% CI 1.02 to 1.19, p=0.010) and women (OR 1.09, 95% CI 1.03 to 1.16, p=0.005). Problem drinking is a major problem in this population and requires urgent interventions to curtail the misuse.
    Journal of epidemiology and community health 01/2014; · 3.04 Impact Factor
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    ABSTRACT: Lipohypertrophy does not appear to be an adverse ART reaction while lipoatrophy is clearly associated with the use of stavudine (d4T) and zidovudine (AZT). In low and middle income countries d4T has only recently been phased out and AZT is still widely being used. Several case definitions have been developed to diagnose lipodystrophy, but none of them are generalizable to sub-Saharan Africa where black women have less visceral adipose tissue and more subcutaneous adipose tissue than white women. We aimed to develop a simple, objective measure to define lipoatrophy and lipohypertrophy by comparing patient report to anthropometric and dual-energy X-ray absorptiometry (DXA) -derived variables.
    AIDS Research and Therapy 01/2014; 11:26. · 2.54 Impact Factor
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    ABSTRACT: Background Primary prevention of cardiovascular disease (CVD),by identifying individuals at risk is a well-established, but costly strategy when based on measurements that depend on laboratory analyses. A non-laboratory, paper-based CVD risk assessment chart tool has previously been developed to make screening more affordable in developing countries. Task shifting to community health workers (CHWs) is being investigated to further scale CVD risk screening. This study aimed to develop a mobile phone CVD risk assessment application and to evaluate it's impact on CHW training and the duration of screening for CVD in the community by CHWs. Methods A feature phone application was developed using the open source online platform, CommCare©. CHWs (n = 24) were trained to use both paper-based and mobile phone CVD risk assessment tools. They were randomly allocated to using one of the risk tools to screen 10-20 community members and then crossed over to screen the same number, using the alternate risk tool. The impact on CHW training time, screening time and margin of error in calculating risk scores was recorded. A focus group discussion evaluated experiences of CHWs using the two tools. Results The training time was 12.3 hrs for the paper-based chart tool and 3 hours for the mobile phone application. 537 people were screened. The mean screening time was 36 minutes (SD = 12.6) using the paper-base chart tool and 21 minutes (SD = 8.71) using the mobile phone application, p = <0.0001. Incorrect calculations (4.3% of average systolic BP measurements, 10.4% of BMI and 3.8% of CVD risk score) were found when using the paper-based chart tool while all the mobile phone calculations were correct. Qualitative findings from the focus group discussion corresponded with the findings of the pilot study. Conclusion The reduction in CHW training time, CVD risk screening time, lack of errors in calculation of a CVD risk score and end user satisfaction when using a mobile phone application, has implications in terms of adoption and sustainability of this primary prevention strategy to identify people with high CVD risk who can be referred for appropriate diagnoses and treatment.
    International Journal of Medical Informatics. 01/2014;
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    ABSTRACT: Patients with Addison's disease (AD) in Scandinavia have an increased risk for premature death due to cardiovascular disease (CVD). Serum lipids are important risk factors for CVD and vascular mortality. Replacement doses of hydrocortisone have historically been higher in Sweden than South Africa. The primary aim was to study the lipid profiles in a large group of patients with AD with the hypothesis that the lipid profile in patients in Sweden would be worse than in South Africa. In a cross-sectional study, 110 patients with AD (55 from South Africa, 55 from Sweden) matched for age, gender, ethnicity and BMI were studied. Anthropometric measures, blood pressure, lipids, highly sensitive C-reactive protein (hs-CRP) and adiponectin were studied. All patients were Caucasian and the majority were women N = 36 (65.5%). Mean (standard deviation; SD) ages of the Swedish and South African patients were 52.9 (13.0) and 52.6 (14.4) years and BMI 25.3 (3.2) and 25.8 (4.1) kg/m2, respectively. The mean total daily hydrocortisone dose was greater in the Swedish patients than the South African patients, [33.0 (8.1) versus 24.3 (8.0) mg; p<0.0001]. South African patients had higher median (interquartilerange; IQR) triglycerides (TG) [1.59 (1.1-2.46) versus 0.96 (0.74-1.6) mmol/l; p<0.001], total cholesterol (TC) [6.02(1.50) versus 5.13 (0.87) mmol/l; p<0.001], LDL-C [4.43 (1.44) versus 2.75 (0.80) mmol/l; p<0.001] and median hs-CRP [2.15 (0.93-5.45) versus 0.99 (0.57-2.10) mg/L; p<0.003] and lower HDL-C [0.80 (0.40) versus 1.86 (0.46) mmol/l; p<0.001] than the Swedish patients. Approximately 20% of the patients in both cohorts had hypertension and diabetes mellitus. South African patients with AD have worse lipid profiles and higher hs-CRP compared to their matched Swedish patients, despite lower doses of hydrocortisone. It is uncertain at this time whether these are due to genetic or environmental factors.
    PLoS ONE 01/2014; 9(3):e90768. · 3.53 Impact Factor
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    ABSTRACT: The number of people with diabetes in Africa is projected to increase substantially in the next two decades, due to factors including rapid urbanisation, adoption of unhealthy diets and exercise patterns and the ageing of the population. There are currently uncertainties regarding the incidence, prevalence and management patterns of diabetes in older people across the diversity of African countries. We wish to perform a systematic review to determine the prevalence of type 2 diabetes in Africa in the older individual, over the age of 55 years, reported in studies from 2000 to 2013.
    BMJ Open 01/2014; 4(6):e004747. · 1.58 Impact Factor
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    ABSTRACT: To ascertain the prevalence and determinants of overweight/obesity in the 25-74-year-old urban black population of Cape Town and examine the changes between 1990 and 2008/09.
    PLoS ONE 01/2014; 9(9):e107471. · 3.53 Impact Factor
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    ABSTRACT: This paper details the hardware and software infrastructure used to collect data and deliver a novel intervention in an on-going individually randomised three-arm parallel group trial in a resource-limited setting. The SMS-text Adherence support trial (StAR) tests the efficacy of a behavioural intervention delivered by SMS-text to support hypertension treatment adherence compared to usual care. The intervention is a structured program of clinic appointment and medication pick-up reminders, medication adherence support and hypertension-related education delivered remotely using an automated system of semi-tailored informational or interactive SMS-text messages delivered to the 1372 recruited participants. The technical infrastructure includes mobile device-based electronic data collection at the point of care with secure remote upload of the data; the intervention delivery system; real-time query identification for screening, enrolment and participant management procedures; and monitoring and evaluation of trial processes. We are using several open-source software platforms in conjunction with off-the-shelf hardware to set-up and run a randomised clinical trial of a novel intervention in a low-resource setting.
    Proceedings of the Sixth International Conference on Information and Communications Technologies and Development: Notes - Volume 2; 12/2013
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    ABSTRACT: BACKGROUND: Sub-Saharan Africa (SSA) has the highest burden of HIV in the world and a rising prevalence of cardiometabolic disease; however, the interrelationship between HIV, antiretroviral therapy (ART) and cardiometabolic traits is not well described in SSA populations. METHODS: We conducted a systematic review and meta-analysis through MEDLINE and EMBASE (up to January 2012), as well as direct author contact. Eligible studies provided summary or individual-level data on one or more of the following traits in HIV+ and HIV-, or ART+ and ART- subgroups in SSA: body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides (TGs) and fasting blood glucose (FBG) or glycated hemoglobin (HbA1c). Information was synthesized under a random-effects model and the primary outcomes were the standardized mean differences (SMD) of the specified traits between subgroups of participants. RESULTS: Data were obtained from 49 published and 3 unpublished studies which reported on 29 755 individuals. HIV infection was associated with higher TGs [SMD, 0.26; 95% confidence interval (CI), 0.08 to 0.44] and lower HDL (SMD, -0.59; 95% CI, -0.86 to -0.31), BMI (SMD, -0.32; 95% CI, -0.45 to -0.18), SBP (SMD, -0.40; 95% CI, -0.55 to -0.25) and DBP (SMD, -0.34; 95% CI, -0.51 to -0.17). Among HIV+ individuals, ART use was associated with higher LDL (SMD, 0.43; 95% CI, 0.14 to 0.72) and HDL (SMD, 0.39; 95% CI, 0.11 to 0.66), and lower HbA1c (SMD, -0.34; 95% CI, -0.62 to -0.06). Fully adjusted estimates from analyses of individual participant data were consistent with meta-analysis of summary estimates for most traits. CONCLUSIONS: Broadly consistent with results from populations of European descent, these results suggest differences in cardiometabolic traits between HIV-infected and uninfected individuals in SSA, which might be modified by ART use. In a region with the highest burden of HIV, it will be important to clarify these findings to reliably assess the need for monitoring and managing cardiometabolic risk in HIV-infected populations in SSA.
    International Journal of Epidemiology 12/2013; 42(6):1754. · 6.98 Impact Factor

Publication Stats

2k Citations
511.19 Total Impact Points

Institutions

  • 1982–2014
    • University of Cape Town
      • • MRC/UCT Research Unit for Exercise Science & Sports Medicine (ESSM)
      • • Faculty of Health Sciences
      • • Department of Human Biology
      • • Department of Medicine
      Kaapstad, Western Cape, South Africa
  • 1994–2013
    • Groote Schuur Hospital
      Kaapstad, Western Cape, South Africa
  • 2011–2012
    • Human Sciences Research Council (HSRC)
      • The Centre for the Study of the Social and Environmental Determinants of Nutrition (CSSEDN)
      Kaapstad, Western Cape, South Africa
    • The National Institute of Diabetes and Digestive and Kidney Diseases
      Maryland, United States
  • 2010
    • Walter Sisulu University
      • Department of Internal Medicine
      Umtata, Province of Eastern Cape, South Africa
  • 2008
    • University of Wollongong
      City of Greater Wollongong, New South Wales, Australia
  • 2004–2008
    • South African Medical Research Council
      • • Chronic Diseases of Lifestyle Research Unit
      • • Burden of Disease Research Unit
      Cape Town, Province of the Western Cape, South Africa
  • 2006–2007
    • Johns Hopkins University
      Baltimore, Maryland, United States
  • 2005
    • University of Limpopo
      • Department of Medical Sciences
      Polokwane, Limpopo Province, South Africa