Browsing by Author "Volmink, J."
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- ItemAchieving the millennium development goals in sub-Saharan Africa(Health and Medical Publishing Group (HMPG), 2007-09) Wiysonge, Charles S.; Young, T.; Volmink, J.To the Editor: The UN has released a mid-term report on progress towards achieving the Millennium Development Goals (MDG), eight pro-poor goals contained in the Millennium Declaration of 2000, to be achieved by 2015. It paints a gloomy picture of health in sub-Saharan Africa. Child mortality rates declined globally, but the improvement was uneven, with sub-Saharan Africa recording the highest rate and the slowest pace of progress. In 1990 and 2005 in sub-Saharan Africa, 185 and 166 children respectively died, mainly from preventable causes, before their 5th birthday for every 1 000 live births, a mere 10% reduction in 16 years.
- ItemBeta‐blockers for hypertension(John Wiley & Sons, Ltd. on behalf of The Cochrane Collaboration, 2017) Wiysonge, Charles S.; Bradley, H. A.; Volmink, J.; Mayosi, B. M.; Opie, L. H.Background: Beta-blockers refer to a mixed group of drugs with diverse pharmacodynamic and pharmacokinetic properties. They have shown longterm beneficial effects on mortality and cardiovascular disease (CVD) when used in people with heart failure or acute myocardial infarction. Beta-blockers were thought to have similar beneficial effects when used as first-line therapy for hypertension. However, the benefit of beta-blockers as first-line therapy for hypertension without compelling indications is controversial. This review is an update of a Cochrane Review initially published in 2007 and updated in 2012. Objectives: To assess the effects of beta-blockers on morbidity and mortality endpoints in adults with hypertension. Search methods: The Cochrane Hypertension Information Specialist searched the following databases for randomized controlled trials up to June 2016: the Cochrane Hypertension Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (2016, Issue 6), MEDLINE (from 1946), Embase (from 1974), and ClinicalTrials.gov. We checked reference lists of relevant reviews, and reference lists of studies potentially eligible for inclusion in this review, and also searched the the World Health Organization International Clinical Trials Registry Platform on 06 July 2015. Selection criteria: Randomised controlled trials (RCTs) of at least one year of duration, which assessed the effects of beta-blockers compared to placebo or other drugs, as first-line therapy for hypertension, on mortality and morbidity in adults. Data collection and analysis: We selected studies and extracted data in duplicate, resolving discrepancies by consensus. We expressed study results as risk ratios (RR) with 95% confidence intervals (CI) and conducted fixed-effect or random-effects meta-analyses, as appropriate.We also used GRADE to assess the certainty of the evidence. GRADE classifies the certainty of evidence as high (if we are confident that the true effect lies close to that of the estimate of effect), moderate (if the true effect is likely to be close to the estimate of effect), low (if the true effect may be substantially different from the estimate of effect), and very low (if we are very uncertain about the estimate of effect). Main results: Thirteen RCTs met inclusion criteria. They compared beta-blockers to placebo (4 RCTs, 23,613 participants), diuretics (5 RCTs, 18,241 participants), calcium-channel blockers (CCBs: 4 RCTs, 44,825 participants), and renin-angiotensin system (RAS) inhibitors (3 RCTs, 10,828 participants). These RCTs were conducted between the 1970s and 2000s and most of them had a high risk of bias resulting from limitations in study design, conduct, and data analysis. There were 40,245 participants taking beta-blockers, threequarters of them taking atenolol. We found no outcome trials involving the newer vasodilating beta-blockers (e.g. nebivolol). There was no difference in all-cause mortality between beta-blockers and placebo (RR 0.99, 95% CI 0.88 to 1.11), diuretics or RAS inhibitors, but it was higher for beta-blockers compared to CCBs (RR 1.07, 95% CI 1.00 to 1.14). The evidence on mortality was of moderate-certainty for all comparisons. Total CVD was lower for beta-blockers compared to placebo (RR 0.88, 95% CI 0.79 to 0.97; low-certainty evidence), a reflection of the decrease in stroke (RR 0.80, 95% CI 0.66 to 0.96; low-certainty evidence) since there was no difference in coronary heart disease (CHD: RR 0.93, 95%CI 0.81 to 1.07; moderate-certainty evidence). The effect of beta-blockers on CVDwas worse than that of CCBs (RR 1.18, 95%CI 1.08 to 1.29; moderate-certainty evidence), but was not different fromthat of diuretics (moderate-certainty) or RAS inhibitors (low-certainty). In addition, there was an increase in stroke in beta-blockers compared to CCBs (RR 1.24, 95% CI 1.11 to 1.40; moderate-certainty evidence) and RAS inhibitors (RR 1.30, 95% CI 1.11 to 1.53; moderate-certainty evidence). However, there was little or no difference in CHD between beta-blockers and diuretics (low-certainty evidence), CCBs (moderate-certainty evidence) or RAS inhibitors (low-certainty evidence). In the single trial involving participants aged 65 years and older, atenolol was associated with an increased CHD incidence compared to diuretics (RR 1.63, 95% CI 1.15 to 2.32). Participants taking beta-blockers were more likely to discontinue treatment due to adverse events than participants taking RAS inhibitors (RR 1.41, 95% CI 1.29 to 1.54; moderate-certainty evidence), but there was little or no difference with placebo, diuretics or CCBs (low-certainty evidence). Authors’ conclusions: Most outcome RCTs on beta-blockers as initial therapy for hypertension have high risk of bias. Atenolol was the beta-blocker most used. Current evidence suggests that initiating treatment of hypertension with beta-blockers leads to modest CVD reductions and little or no effects on mortality. These beta-blocker effects are inferior to those of other antihypertensive drugs. Further research should be of high quality and should explore whether there are differences between different subtypes of beta-blockers or whether beta-blockers have differential effects on younger and older people.
- ItemCo-trimoxazole prophylaxis in HIV : the evidence(Health and Medical Publishing Group (HMPG), 2008-04) Oliphant, C. E. M.; Young, T.; Araoyinbo, I.; Volmink, J.Human immunodeficiency virus (HIV) damages the body’s immune system, making secondary (or opportunistic) infections more common. Treatment and prevention of such infections is integral to the management of patients with HIV infection. Co-trimoxazole is a prophylactic treatment that has a wide range of action against common bacteria, parasites, fungi and yeasts. As part of a minimum care package, UNAIDS/ WHO recommends co-trimoxazole prophylaxis for HIVinfected adults with symptomatic disease (WHO stage II, III or IV), or asymptomatic individuals with CD4 counts ≤500 cells/μl, and for all HIV-positive pregnant women after the first trimester.1 Co-trimoxazole is also recommended for use in children with proven HIV infection and infants exposed to HIV (from 4 - 6 weeks of age until infection with HIV is ruled out).2 The object of this report is to summarise the effects of co-trimoxazole prophylaxis on morbidity and mortality among HIV-infected individuals.
- ItemDoes South Africa need a national clinical trials support unit?(Health and Medical Publishing Group (HMPG), 2010) Siegfried, N.; Volmink, J.; Dhansay, A.Background. No national South African institution provides a coherent suite of support, available skills and training for clinicians wishing to conduct randomised controlled trials (RCTs) in the public sector. We report on a study to assess the need for establishing a national South African Clinical Trials Support Unit. Objectives. To determine the need for additional training and support for conduct of RCTs within South African institutions; identify challenges facing institutions conducting RCTs; and provide recommendations for enhancing trial conduct within South African public institutions. Design. Key informant interviews of senior decision-makers at institutions with a stake in the South African public sector clinical trials research environment. Results. Trial conduct in South Africa faces many challenges, including lack of dedicated funding, the burden on clinical load, and lengthy approval processes. Strengths include the high burden of disease and the prevalence of treatmentnaïve patients. Participants expressed a significant need for a national initiative to support and enhance the conduct of public sector RCTs. Research methods training and statistical support were viewed as key. There was a broad range of views regarding the structure and focus of such an initiative, but there was agreement that the national government should provide specific funding for this purpose. Conclusions. Stakeholders generally support the establishment of a national clinical trials support initiative. Consideration must be given to the sustainability of such an initiative, in terms of funding, staffing, expected research outputs and permanence of location.
- ItemEducational factors that influence the urban-rural distribution of health professionals in South Africa : a case-control study(Health and Medical Publishing Group (HMPG), 2011-01) Reid, S. J.; Couper, I. D.; Volmink, J.Setting. The influence of undergraduate and postgraduate training on health professionals' career choices in favour of rural and underserved communities has not been clearly demonstrated in resourceconstrained settings. Objectives. This study aimed to evaluate the influence of educational factors on the choice of rural or urban sites of practice of health professionals in South Africa. Methods. Responses to a questionnaire on undergraduate and postgraduate educational experiences by 174 medical practitioners in rural public practice were compared with those from 142 urban public hospital doctors. Outcomes measured included specific undergraduate and postgraduate educational experiences, and noneducational factors such as family and community influences that were likely to affect the choice of the site of practice. Results. Compared with urban doctors, rural respondents were significantly less experienced, more likely to be black, and felt significantly more accountable to the community that they served. They were more than twice as likely as the urban group to have been exposed to rural situations during their undergraduate training, and were also five times more likely than urban respondents to state that exposure to rural practice as an undergraduate had influenced their choice of where they practise. Urban respondents were significantly more attracted to working where they do by professional development and postgraduate education opportunities and family factors than the rural group. Conclusions. Evidence is provided that rural exposure influences the choice of practice site by health professionals in a developing country context, but the precise curricular elements that have the most effect deserve further research.
- ItemInterventions for improving childhood vaccination coverage in low- and middle-income countries(Health & Medical Publishing Group, 2015) Wiysonge, Charles S.; Young, T.; Kredo, T.; McCaul, M.; Volmink, J.Cochrane Corner’ in the November SAMJ highlights a Cochrane review that evaluated the effects of interventions for improving childhood vaccination coverage in low- and middle-income countries. Question: Which interventions increase the uptake of childhood vaccines in low and middle-income countries? Bottom line: Health education, home visits, and reminders probably increase the uptake of childhood vaccines in low and middle-income countries.
- ItemNutritional supplements for people being treated for active tuberculosis(2008) Abba, K.; Sudarsanam, T. D.; Grobler, L.; Volmink, J.Background: Tuberculosis is a serious infection affecting mainly the lungs. It may contribute to nutritional deficiencies which in turn may delay recovery by depressing immune functions. Nutritional supplements might therefore promote recovery in people being treated for tuberculosis. Objectives: To assess the provision of oral nutritional supplements to promote the recovery of people being treated with antituberculous drug therapy for active tuberculosis. Search strategy: We searched the Cochrane Infectious Disease Group Specialized Register (June 2008), CENTRAL (The Cochrane Library 2008, Issue 2), MEDLINE (June 2008), EMBASE (June 2008), LILACS (June 2008), mRCT (June 2008), the Indian Journal of Tuberculosis (1983 to June 2008), and checked the reference lists of all included studies. Selection criteria: Randomized controlled trials comparing any oral nutritional supplement given for at least four weeks with no nutritional intervention, placebo, or dietary advice only for people being treated for active tuberculosis. Data collection and analysis: Two authors independently selected trials, extracted data, and assessed risk of bias. We calculated risk ratios (RR) for dichotomous variables and mean differences (MD) for continuous variables, with 95% confidence intervals (CI). We pooled data from trials with similar interventions and outcomes. Main results: Twelve trials (3393 participants) were included. Five trials had adequate allocation concealment. Interventions included a high energy supplement, high cholesterol diet, vitamin D, vitamin A, zinc, arginine, multiple micronutrient supplements, combined multiple micronutrient supplements and zinc, combined vitamin A and zinc, and combined vitamin A and selenium. The following supplements were associated with increased body weight at follow up: high energy supplements (MD 1.73 kg, 95% CI 0.81 to 2.65; 34 participants, 1 trial); multiple micronutrients plus additional zinc (MD 2.37 kg, 95% CI 2.21 to 2.53; 192 participants, 1 trial); and vitamin A plus zinc (MD 3.10 kg, 95% CI 0.74 to 5.46; 80 participants, 1 trial). There was no evidence that any supplement affected the number of deaths or number of participants with sputum test positive results at the end of treatment. Authors' conclusions: There is limited evidence that high energy supplements and some combinations of zinc with other micronutrients may help people with tuberculosis to gain weight. There is not enough evidence to assess the effect of other combinations of nutrients. A number of relevant trials are in progress, and, where appropriate, the results will be incorporated into future updates of this review. Copyright © 2008 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
- ItemRestricting or banning alcohol advertising to reduce alcohol consumption in adults and adolescents (Review)(2014) Parry, C. D. H.; Jere, M.; Kredo, T.; Volmink, J.; Ataguba, J. E.; Pienaar, D. C.; Siegfried, N.Background: Alcohol is estimated to be the fifth leading risk factor for global disability-adjusted life years. Restricting or banning alcohol advertising may reduce exposure to the risk posed by alcohol at the individual and general population level. To date, no systematic review has evaluated the effectiveness, possible harms and cost-effectiveness of this intervention. Objectives: To evaluate the benefits, harms and costs of restricting or banning the advertising of alcohol, via any format, compared with no restrictions or counter-advertising, on alcohol consumption in adults and adolescents.
- ItemRisk of cardiovascular disease among teachers in Cape Town : findings of the South African PaCT pilot study(Health & Medical Publishing Group, 2016) Laurence, E. C.; Volmink, J.; Esterhuizen, T. M.; Dalal, S.; Holmes, M. D.Background. The accelerating epidemic of cardiovascular disease (CVD) and other non-communicable diseases (NCDs) highlights the need to establish long-term cohort studies in Africa. Objective. The Partnership for Cohort Research and Training (PaCT) seeks to study NCDs in South Africa (SA), Uganda, Tanzania and Nigeria on a long-term basis. Pilot studies at each site have tested feasibility. The SA site additionally studied the prevalence of CVD risk factors and categorised participants’ 10-year predicted risk of a cardiovascular event. Methods. We enrolled teachers from 111 public schools in the Metro South Education District in Cape Town, SA, between January 2011 and May 2012. Participants completed a self-administered questionnaire and biological measurements, and chose post or email for 6-month follow-up. Results. The participation of schools was permitted by 53.2% of principals, and 489 of 1 779 teachers agreed to participate. Of teachers willing to participate in the follow-up, 52% were retained, three-quarters by post and a quarter by email. Their mean age was 46.3 years and 70.3% were female. The prevalence of CVD risk factors was high and featured hypertension (48.5%), hypercholesterolaemia (20.5%), smoking (18.0%), diabetes (10.1%) and chronic kidney disease (10.4%), while 84.7% were overweight or obese. Of the participants, 18.7% were at high risk of a heart attack or stroke within 10 years. Conclusion. Establishing a cohort study among teachers has challenges but also opportunities for addressing CVD, which will soon impose a substantial burden on Cape Town’s education system.
- ItemSouth African medical schools : current state of selection criteria and medical students’ demographic profile(Health & Medical Publishing Group, 2016-01) Van der Merwe, L. J.; Van Zyl, G. J.; St. Clair Gibson, A.; Viljoen, M.; Iputo, J. E.; Mammen, M.; Chitha, W.; Perez, A. M.; Hartman, N.; Fonn, S.; Green-Thompson, L.; Ayo-Ysuf, O. A.; Botha, G. C.; Manning, D.; Botha, S. J.; Hift, R.; Retief, P.; Van Heerden, B. B.; Volmink, J.ENGLISH SUMMARY : Background: Selection of medical students at South African (SA) medical schools must promote equitable and fair access to students from all population groups, while ensuring optimal student throughput and success, and training future healthcare practitioners who will fulfil the needs of the local society. In keeping with international practices, a variety of academic and non-academic measures are used to select applicants for medical training programmes in SA medical schools. Objectives: To provide an overview of the selection procedures used by all eight medical schools in SA, and the student demographics (race and gender) at these medical schools, and to determine to what extent collective practices are achieving the goals of student diversity and inclusivity. Methods: A retrospective, quantitative, descriptive study design was used. All eight medical schools in SA provided information regarding selection criteria, selection procedures, and student demographics (race and gender). Descriptive analysis of data was done by calculating frequencies and percentages of the variables measured. Results: Medical schools in SA make use of academic and non-academic criteria in their selection processes. The latter include indices of socioeconomic disadvantage. Most undergraduate medical students in SA are black (38.7%), followed by white (33.0%), coloured (13.4%) and Indian/Asian (13.6%). The majority of students are female (62.2%). The number of black students is still proportionately lower than in the general population, while other groups are overrepresented. Conclusion: Selection policies for undergraduate medical programmes aimed at redress should be continued and further refined, along with the provision of support to ensure student success.
- ItemTask-shifting from doctors to non-doctors for initiation and maintenance of antiretroviral therapy(Health and Medical Publishing Group, 2015) Kredo, T.; McCaul, M.; Volmink, J.'Cochrane Corner’ in the August SAMJ offers evidence relating to articles published in this issue, namely ‘Improving access to antiretrovirals in rural South Africa – a call to action’, ‘Multimorbidity, control and treatment of non-communicable diseases among primary healthcare attenders in the Western Cape, South Africa’ and ‘Prevalence of tobacco use among adults in South Africa: Results from the first South African National Health and Nutrition Examination Survey’, and the editorial by Yach and Alexander, ‘Turbo-charging tobacco control in South Africa’.