Browsing by Subject "Risk"

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    Adolescent and young pregnant women at increased risk of mother-to-child transmission of HIV and poorer maternal and infant health outcomes: A cohort study at public facilities in the Nelson Mandela Bay Metropolitan district, Eastern Cape, South Africa
    (2014) Fatti, Geoffrey; Shaikh, Najma; Eley, Brian; Jackson, Debra; Grimwood, Ashraf
    BACKGROUND: South Africa (SA) has the highest burden of childhood HIV infection globally, and has high rates of adolescent and youth pregnancy OBJECTIVE: To explore risks associated with pregnancy in young HIV-infected women, we compared mother-to-child transmission (MTCT) of HIV and maternal and infant health outcomes according to maternal age categories METHODS: A cohort of HIV-positive pregnant women and their infants were followed up at three sentinel surveillance facilities in the Nelson Mandela Bay Metropolitan (NMBM) district, Eastern Cape Province, SA. Young women were defined as 24 years as the comparison group RESULTS: Of 956 mothers, 312 (32.6%) were young women; of these, 65 (20.8%) were adolescents. The proportion of young pregnant women increased by 24% between 2009/10 and 2011/12 (from 28.3% to 35.1%). Young women had an increased risk of being unaware of their HIV status when booking (adjusted risk ratio (aRR) 1.37; 95% confidence interval (CI) 1.21 - 1.54), a reduced rate of antenatal antiretroviral therapy (ART) uptake (adjusted hazard ratio 0.46; 95% CI 0.31 - 0.67), reduced early infant HIV diagnosis (aRR 0.94; 95% CI 0.94 - 0.94), and increased MTCT (aRR 3.07; 95% CI 1.18 - 7.96; adjusted for ART use). Of all vertical transmissions, 56% occurred among young women. Additionally, adolescents had increased risks of first presentation during labour (aRR 3.78; 95% CI 1.06 - 13.4); maternal mortality (aRR 35.1; 95% CI 2.89 - 426) and stillbirth (aRR 3.33; 95% CI 1.53 - 7.25 CONCLUSION: An increasing proportion of pregnant HIV-positive women in NMBM were young, and they had increased MTCT and poorer maternal and infant outcomes than older women. Interventions targeting young women are increasingly needed to reduce pregnancy, HIV infection and MTCT and improve maternal and infant outcomes if SA is to attain its Millennium Development Goals
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    Association between ethnicity and obesity with high-density lipoprotein (HDL) function and subclass distribution
    (2016) Woudberg, Nicholas J; Goedecke, Julia H; Blackhurst, Dee; Frias, Miguel; James, Richard; Opie, Lionel H; Lecour, Sandrine
    Abstract Background Obesity and low high-density lipoprotein-cholesterol (HDL-C) levels are associated with cardiovascular risk. Surprisingly, despite a greater prevalence of obesity and lower HDL concentrations than white women, black South African women are relatively protected against ischaemic heart disease. Methods We investigated whether this apparent discrepancy may be related to different HDL function and subclass distribution in black and white, normal-weight and obese South African women (n = 40). HDL functionality was assessed by measuring paraoxonase (PON) activity, platelet activating factor acetylhydrolase (PAF-AH) activity, Oxygen Radical Absorbance Capacity (ORAC) and quantification of the expression of vascular cell adhesion molecule in endothelial cells. PON-1 and PAF-AH expression was determined in isolated HDL and serum using Western blotting. Levels of large, intermediate and small HDL subclasses were measured using the Lipoprint® system. Results PON activity was lower in white compared to black women (0.49 ± 0.09 U/L vs 0.78 ± 0.10 U/L, p < 0.05), regardless of PON-1 protein levels. Obese black women had lower PAF-AH activity (9.34 ± 1.15 U/L vs 13.89 ± 1.21 U/L, p <0.05) and HDL-associated PAF-AH expression compared to obese white women. Compared to normal-weight women, obese women had lower large HDL, greater intermediate and small HDL; an effect that was more pronounced in white women than black women. There were no differences in antioxidant capacity or anti-inflammatory function across groups. Conclusions Our data show that both obesity and ethnicity are associated with differences in HDL functionality, while obesity was associated with decreases in large HDL subclass distribution. Measuring HDL functionality and subclass may, therefore, be important factors to consider when assessing cardiovascular risk.
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    Guideline for the management of acute asthma in adults: 2013 update
    (2013) Lalloo, U G; Ainslie, G M; Abdool-Gaffar, M S; Awotedu, A A; Feldman, C; Greenblatt, M; IRUSEN, E M; Mash, R; Naidoo, S S; O\'Brien, J; Otto, W; Richards, G A; Wong,, M L
    Acute asthma attacks (asthma exacerbations) are increasing episodes of shortness of breath, cough, wheezing or chest tightness associated with a decrease in airflow that can be quantified and monitored by measurement of lung function (peak expiratory flow (PEF) or forced expiratory volume in the 1st second) and requiring emergency room treatment or admission to hospital for acute asthma and/or systemic glucocorticosteroids for management. The goals of treatment are to relieve hypoxaemia and airflow obstruction as quickly as possible, restore lung function, and provide a suitable plan to avoid relapse. Severe exacerbations are potentially life-threatening and their treatment requires baseline assessment of severity, close monitoring, and frequent reassessment using objective measures of lung function (PEF) and oxygen saturation. Patients at high risk of asthma-related death require particular attention. First-line therapy consists of oxygen supplementation, repeated administration of inhaled short-acting bronchodilators (beta-2-agonists and ipratropium bromide), and early systemic glucocorticosteroids. Intravenous magnesium sulphate and aminophylline are second- and third-line treatment strategies, respectively, for poorly responding patients. Intensive care is indicated for severe asthma that is not responsive to first-line treatment. Antibiotics are only indicated when there are definite features of bacterial infection. Factors that precipitated the acute asthma episode should be identified and preventive measures implemented. Acute asthma is preventable with optimal control of chronic asthma.
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    Is air pollution a risk factor for rheumatoid arthritis?
    (2015) Essouma, Mickael; Noubiap, Jean Jacques N
    Rheumatoid arthritis is a chronic inflammatory debilitating disease triggered by a complex interaction involving genetic and environmental factors. Active smoking and occupational exposures such as silica increase its risk, suggesting that initial inflammation and generation of rheumatoid arthritis-related autoantibodies in the lungs may precede the clinical disease. This hypothesis paved the way to epidemiological studies investigating air pollution as a potential determinant of rheumatoid arthritis. Studies designed for epidemiology of rheumatoid arthritis found a link between traffic, a surrogate of air pollution, and this disease. Furthermore, a small case–control study recently found an association between wood smoke exposure and anticyclic citrullinated protein/peptide antibody in sera of patients presenting wood-smoke-related chronic obstructive pulmonary disease. However, reports addressing impact of specific pollutants on rheumatoid arthritis incidence and severity across populations are somewhat conflicting. In addition to the link reported between other systemic autoimmune rheumatic diseases and particulate matters/gaseous pollutants, experimental observation of exacerbated rheumatoid arthritis incidence and severity in mice models of collagen-induced arthritis after diesel exhaust particles exposure as well as hypovitaminosis D-related autoimmunity can help understand the role of air pollution in rheumatoid arthritis. All these considerations highlight the necessity to extend high quality epidemiological researches investigating different sources of atmospheric pollution across populations and particularly in low-and-middle countries, in order to further explore the biological plausibility of air pollution’s effect in the pathogenesis of rheumatoid arthritis. This should be attempted to better inform policies aiming to reduce the burden of rheumatoid arthritis.
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    Is the management procedure approach equipped to handle short-lived pelagic species with their boom and bust dynamics? The case of the South African fishery for sardine and anchovy
    (Oxford University Press, 2011) De Moor, Carryn L; Butterworth, Doug S; De Oliveira, J A A
    Worldwide, small shoaling pelagic fish manifest rapid and substantial natural changes in abundance. Is the application of a management procedure (MP), evaluated using simulation tests [i.e. a MP approach otherwise known as management strategy evaluation (MSE)], to recommend total allowable catches (TACs) with constraints desired by industry on the extent of interannual changes viable for such resources, particularly given the customarily lengthy MP evaluation process? This question is examined by considering the rapid boom and then bust situation that arose for the South African fishery for sardine (Sardinops sagax) and anchovy (Engraulis encrasicolus) across the turn of the century. Novel adaptations to the MP in place at the time of the boom allowed enhanced resource use during the boom period without compromising the risk of unintended depletion of the populations. Importantly a two-tier threshold system allowed the normal constraints on the maximum extent of interannual TAC reduction to be modified when TACs rose above the specified thresholds. The general protocol underlying the application of MPs for South African fisheries proved sufficiently flexible for the approach to continue to be applied, despite the unanticipated rapid fish population boom and then bust experienced.
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    Limits to the use of environmental indices to reduce risk and/or increase yield in the South African anchovy fishery
    (National Inquiry Services Centre, 2005) De Oliveira, J A A; Butterworth, Doug S
    Environmental indices that provide short-term predictions of recruitment have the potential to improve the average yield from highly productive resources that sustain recruit fisheries without an associated increase in risk (of resource 'collapse'). This is particularly true for cases where a measurement of recruitment is not available until after substantial fishing on this recruitment has already taken place. The South African anchovy Engraulis encrasicolus resource reflects such a situation, and forms the basis for a simulation study to investigate the benefits of using environmental indices to set appropriate Total Allowable Catches (TACs). Simulations, based on a 'management procedure' (sensu the International Whaling Commission), investigate how such benefits are related to the proportion of variation in recruitment explained by the environmental index. Furthermore, they evaluate to what extent these benefits are compromised by uncertainties related to the degrees of freedom effect (over-fitting data), the selection of explanatory variables (danger of spurious correlations), and errors in the values of explanatory variables (including measurement error). Five recruitment prediction models that incorporate increasing numbers of these uncertainties are investigated. These predictions are used to adjust TACs depending on whether they indicate forthcoming recruitment to be in the top or bottom third of the distribution of possible recruitment values. Results indicate that an environmental index needs to explain roughly 50% or more of the total variation in recruitment (r2 ≥ 0.5) before the management procedure starts showing benefits in terms of the summary performance statistics for risk and average catch. Comparable benefits are possible at a lower r2 value when TAC constraints are removed, but there is then a large associated increase in interannual catch variation. When r2 is low, performance in terms of average catch may prove worse if attempting to take account of an environmental variable in setting the TAC than ignoring it.
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    Managing risk with insurance and savings: Experimental evidence for male and female farm managers in the Sahel
    (2015-05-28) Delavallade, Clara; Dizon, Felipe; Hill, Ruth; Petraud, Jean Paul
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    Microalbuminuria risks and glomerular filtration in children with sickle cell anaemia in Nigeria
    (2019-11-12) Ocheke, I. E; Mohamed, S.; Okpe, E. S; Bode-Thomas, F.; McCullouch, M. I
    Abstract Introduction Evidence of kidney damage is observed in children with sickle cell anaemia (SCA) and this continues through adulthood with progression to severe functional impairment in some. One of the earliest features of kidney damage associated with SCA is microalbuminuria. Our objective was to determine the risk factors of microalbuminuria in these children and its relationship with estimated glomerular filtration rate. Methods This was a cross-sectional and comparative study involving three hundred and twenty three children with SCA in steady state and equal numbers of apparently healthy age and sex matched haemoglobin AA (HbAA) control, aged 6 months to 18 years. They were consecutively recruited over a 6 month period. Result Microalbuminuria was present in 26% of the study subjects compared with 1.85% of control P = 0.001). Anaemia and high estimated glomerular filtration rate (eGFR) showed strong positive correlation with microalbuminuria (OR = 3.19, CI 0.953–1.116, p = 0.003 and OR = 1.7, CI 1.042–1.066, p = 0.001 respectively). Similarly, eGFR was higher in subjects with SCA than in controls and as well as in those with microalbuminuria compared with those who do not (p = < 0.01). Conclusions The two most important risk factors for microalbuminuria were anaemia and high eGFR. Age category was associated more with microalbuminuria than just age as a variable. Glomerular filtration rate was higher in children with microalbuminuria than those who do not and it was also higher in children with SCA than in control.
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    No evidence for association of insulin receptor substrate-1 Gly972Arg variant with type 2 diabetes mellitus in a mixed-ancestry population of South Africa
    (2014) Vergotine, Zelda; Kengne, André Pascal; Erasmus, Rajiv Timothy; Matsha, Tandi Edith
    BACKGROUND: The most common single-nucleotide polymorphism in the insulin receptor substrate-1 (IRS1) gene is Gly972Arg, which is associated with a 25% increased risk of developing diabetes. The mixed-ancestry population of South Africa (SA) has one of the highest prevalences of type 2 diabetes mellitus (T2DM) in Africa. OBJECTIVE: To report the frequency of IRS1 Gly972Arg and investigate its associations with cardiometabolic traits. METHODS: DNA from 856 mixed-ancestry adults drawn from an urban community of Bellville South, Cape Town, SA, was genotyped by two independent laboratories. Oral glucose tolerance tests were performed and cardiometabolic risk factors measured. RESULTS: A total of 237 (24.7%) participants had T2DM. The IRS1 Gly972Arg variant was present in 7.9% of the individuals studied and only one participant (non-diabetic) carried the homozygous A/A variant. In linear and logistic regression analyses, Gly972Arg was not associated with obesity, insulin resistance/sensitivity or T2DM. CONCLUSIONS: The prevalence of the Gly972Arg variant in the mixed-ancestry population of SA is comparable to that reported in African Americans, but its presence is not associated with cardiometabolic traits. This suggests that the Gly972Arg variant may not aid diabetes risk evaluation in this setting, nor can such information help explain the high prevalence of diabetes previously reported in this population.
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    Osteoprotegerin in relation to insulin resistance and blood lipids in sub-Saharan African women with and without abdominal obesity
    (2015) Ayina Ayina, Clarisse Noël; Sobngwi, Eugène; Essouma, Mickael; Noubiap, Jean Jacques N; Boudou, Philippe; Etoundi Ngoa, Laurent Serge; Gautier, Jean François
    BackgroundOsteoprotegerin (OPG), a soluble member of the tumor necrosis factor receptor superfamily that inhibits bone resorption, has been suggested as a potential marker of cardiovascular risk. This study aimed to assess the relationship between insulin resistance, lipid profile and OPG levels in obese and non-obese sub-Saharan African women.MethodsSixty obese (44) and non-obese (16) volunteer women aged 18 to 40years were recruited in this cross-sectional study. Their clinical (age, height, weight, waist circumference, systolic and diastolic blood pressures) and biochemical parameters (fasting blood glucose, total cholesterol, high density lipoprotein-cholesterol (HDL-C)) were measured using standard methods. Insulin levels were measured using an electrochemiluminescence immunoassay, while OPG levels were measured using the ELISA technique. Low density lipoprotein-cholesterol (LDL-C), body mass index (BMI) and Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) were calculated using standard methods. Abdominal obesity was defined as a waist circumference ≥ 80cm.ResultsOPG levels were higher in obese than in normal subjects, though the difference was not significant (p = 0.9). BMI, waist circumference, percent body fat and systolic blood pressure were significantly higher in obese than in non-obese subjects (p < 0.05). In these subjects, only age significantly correlated with OPG levels (r = 0.831, p = 0.003), while none of the anthropometric nor metabolic parameter did, even after adjustment for age. In obese subjects, OPG levels fairly correlated with HDL-C (r = 0.298, p = 0.058), and significantly correlated with HOMA-IR (r = −0.438, p = 0.018). After adjustment for age, OPG levels remained negatively correlated to HOMA-IR (r = −0.516, p = 0.020) and LDL-C (r = −0.535, p = 0.015) and positively correlated to HDL-C (r = 0.615, p = 0.004). In multiple linear regression analysis, age was a main determinant of OPG levels in non-obese (β = 0.647, p = 0.006) and obese (β = 0.356, p = 0.044) women. HDL-C was also associated to OPG levels in obese women (β = 0.535, p = 0.009).ConclusionThe positive correlation of OPG with HDL-C and HOMA-IR, and its negative correlation with LDL-C suggest that it may be a marker of insulin sensitivity/resistance and atherogenic risk in obese African women.
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    Prevention of diseases after menopause
    (2014) Lobo, R A; Davis, S R; de Villiers, T J; Gompel, A; Henderson, V W; Hodis, H N; Lumsden, M A; Mack, W J; Shapiro, S; Baber, R J
    AbstractWomen may expect to spend more than a third of their lives after menopause. Beginning in the sixth decade, many chronic diseases will begin to emerge, which will affect both the quality and quantity of a woman's life. Thus, the onset of menopause heralds an opportunity for prevention strategies to improve the quality of life and enhance longevity. Obesity, metabolic syndrome and diabetes, cardiovascular disease, osteoporosis and osteoarthritis, cognitive decline, dementia and depression, and cancer are the major diseases of concern. Prevention strategies at menopause have to begin with screening and careful assessment for risk factors, which should also include molecular and genetic diagnostics, as these become available. Identification of certain risks will then allow directed therapy. Evidence-based prevention for the diseases noted above include lifestyle management, cessation of smoking, curtailing excessive alcohol consumption, a healthy diet and moderate exercise, as well as mentally stimula...
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    Recommendations for amniocentesis in HIV-positive women
    (2014) Constantatos, Sonia Nicola; Boutall, Alison H; Stewart, Chantal J
    There is limited literature on the known risk of HIV transmission during amniocentesis. Before the introduction of highly active antiretroviral therapy (HAART), amniocentesis was avoided owing to the increased risk of HIV transmission. Recent literature suggests that it is safe to perform amniocentesis in women on HAART with undetectable viral loads. In South Africa (SA), many women access antenatal care late in pregnancy and there is often insufficient time to attain undetectable viral loads within a pre-viability period. Guidelines and recommendations for invasive testing in HIV-positive women in the SA setting are lacking. This article provides recommendations to healthcare practitioners who are faced with an HIV-positive patient requiring amniocentesis.
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    Reporting and handling of missing data in predictive research for prevalent undiagnosed type 2 diabetes mellitus: a systematic review
    (BioMed Central Ltd, 2015) Masconi, Katya L; Matsha, Tandi; Echouffo-Tcheugui, Justin; Erasmus, Rajiv; Kengne, Andre
    Missing values are common in health research and omitting participants with missing data often leads to loss of statistical power, biased estimates and, consequently, inaccurate inferences. We critically reviewed the challenges posed by missing data in medical research and approaches to address them. To achieve this more efficiently, these issues were analyzed and illustrated through a systematic review on the reporting of missing data and imputation methods (prediction of missing values through relationships within and between variables) undertaken in risk prediction studies of undiagnosed diabetes. Prevalent diabetes risk models were selected based on a recent comprehensive systematic review, supplemented by an updated search of English-language studies published between 1997 and 2014. Reporting of missing data has been limited in studies of prevalent diabetes prediction. Of the 48 articles identified, 62.5% (n=30) did not report any information on missing data or handling techniques. In 21 (43.8%) studies, researchers opted out of imputation, completing case-wise deletion of participants missing any predictor values. Although imputation methods are encouraged to handle missing data and ensure the accuracy of inferences, this has seldom been the case in studies of diabetes risk prediction. Hence, we elaborated on the various types and patterns of missing data, the limitations of case-wise deletion and state-of the-art methods of imputations and their challenges. This review highlights the inexperience or disregard of investigators of the effect of missing data in risk prediction research. Formal guidelines may enhance the reporting and appropriate handling of missing data in scientific journals.
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    Sensory neuropathy and metabolic risk factors in human immune deficiency virus infected South Africans receiving protease inhibitors
    (2015) Vermaak, John-Randel; Dave, Joel A; Levitt, Naomi; Heckmann, Jeannine M
    BackgroundProtease inhibitors (PI)s have been associated with distal sensory polyneuropathy (DSP) and metabolic complications in high-income countries. No data exist in Africans where second-line antiretroviral therapy (ART) often include PIs.MethodWe performed a cross-sectional study to assess the DSP frequency and metabolic risk factors in community-based South Africans taking ritonavir-boosted lopinavir as PI. Examination findings categorized subjects as having DSP (≥1 neuropathic sign) or symptomatic DSP [DSP with symptom(s)]. Fasting-state glucose and lipid profiles were assessed. We compared the ritonavir/lopinavir-group to a nested group on first-line ART [dideoxy-nucleoside reverse transcriptase inhibitors (d-drugs)] selected from a dataset collected at the same time and matched for d-drug exposure.ResultsThe ritonavir/lopinavir-group (n=86) consisted predominantly of women (84%) with a median age of 36years (IQR 32–41). The median current CD4+ count was 489cells/μL (IQR 291–665). The median exposure time to ritonavir/lopinavir was 18months (IQR 10–26) and to d-drugs, 24months (IQR 16–38). DSP was present in 78% and symptomatic DSP in 48%; symptoms were most frequently of moderate intensity. Only age independently associated with DSP and symptomatic DSP (p=0.08 and p=0.04, respectively). None of the metabolic syndrome components showed associations with DSP or symptomatic DSP despite a trend towards hypertriglyceridemia overall. The ritonavir/lopinavir-group had less DSP compared to the d-drug only group (p=0.002) but the frequency of symptomatic DSP was similar (p=0.49).ConclusionRitonavir-boosted lopinavir did not add additional risk to developing DSP in this community-based African cohort after a median of 18months on second-line ART.Electronic supplementary materialThe online version of this article (doi:10.1186/s12981-015-0073-8) contains supplementary material, which is available to authorized users.
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    South African tobacco smoking cessation clinical practice guideline
    (2013) van Zyl-Smit, Richard N; Allwood, Brian; Stickells, David; Symons, Gregory; Abdool-Gaffar, Sabs; Murphy, Kathy; Lalloo, Umesh; Vanker, Aneesa; Sabur, Natasha F; Richards, Guy
    Tobacco smoking (i.e. cigarettes, rolled tobacco, pipes, etc.) is associated with significant health risks, reduced life expectancy and negative personal and societal economic impact. Smokers have an increased risk of cancer (i.e. lung, throat, bladder), chronic obstructive pulmonary disease (COPD), tuberculosis and cardiovascular disease (i.e. stroke, heart attack). Smoking affects unborn babies, children and others exposed to second hand smoke. Stopping or 'quitting' is not easy. Nicotine is highly addictive and smoking is frequently associated with social activities (e.g. drinking, eating) or psychological factors (e.g. work pressure, concerns about body weight, anxiety or depressed mood). The benefits of quitting, however, are almost immediate, with a rapid lowering of blood pressure and heart rate, improved taste and smell, and a longer-term reduction in risk of cancer, heart attack and COPD. Successful quitting requires attention to both the factors surrounding why an individual smokes (e.g. stress, depression, habit, etc.) and the symptoms associated with nicotine withdrawal. Many smokers are not ready or willing to quit and require frequent motivational input outlining the benefits that would accrue. In addition to an evaluation of nicotine dependence, co-existent medical or psychiatric conditions and barriers to quitting should be identified. A tailored approach encompassing psychological and social support, in addition to appropriate medication to reduce nicotine withdrawal, is likely to provide the best chance of success. Relapse is not uncommon and reasons for failure should be addressed in a positive manner and further attempts initiated when the individual is ready. Key steps in smoking cessation include: (i) identifying all smokers, alerting them to the harms of smoking and benefits of quitting; (ii) assessing readiness to initiate an attempt to quit; (iii) assessing the physical and psychological dependence to nicotine and smoking; (iv) determining the best combination of counselling/support and pharmacological therapy; (v) setting a quit date and provide suitable resources and support; (vi) frequent follow-up as often as possible via text/telephone or in person; (vii) monitoring for side-effects, relapse and on-going cessation; and (viii) if relapse occurs, providing the necessary support and encourage a further attempt when appropriate.
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    Systematic review of the evidence for rational dosing of colistin
    (2014) Visser Kift, E; Maaartens, G; Bamford, C
    BACKGROUND: There is an alarming global increase in the incidence of nosocomial infections with multidrug-resistant Gram-negative bacteria, which are often only susceptible to colistin. Colistin was developed prior to current methods of establishing dosing using pharmacokinetic-pharmacodynamic relationships. Dosing regimens differ in package inserts from different manufacturers and in different guidelines. It is imperative to avoid under-dosing with colistin in order to limit the development of resistance, as it is the last line of defence. METHODS: We conducted a systematic review of the literature to develop guidelines for rational dosing of intravenous colistin, with a particular focus on critically ill patients. RESULTS: Colistin is administered as the inactive pro-drug colistimethate sodium. Colistin demonstrates concentration-dependent bacterial killing, suggesting that higher doses should be administered less frequently to achieve higher peak concentrations. Dose-related nephrotoxicity occurs, making it impossible to safely achieve concentrations that prevent the selection of resistant mutants or the effective eradication of bacteria with higher minimum inhibitory concentrations. Theoretically, combination therapy should be used to reduce the risk of selection of resistant bacteria. In critically ill patients, a loading dose should be given to rapidly achieve therapeutic concentrations, followed by maintenance doses of 4.5 MU 12-hourly. Maintenance dose adjustment is necessary with renal impairment. CONCLUSION: Easier access to colistin is needed in South Africa, where it is not a registered medicine. Further research is needed to better characterise colistin's pharmacokinetic-pharmacodynamic relationships in humans and to establish whether combinations of colistin with other antimicrobials result in improved clinical outcomes or a reduction in selection of resistant bacteria.
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    The association between HIV and atherosclerotic cardiovascular disease in sub-Saharan Africa: a systematic review
    (2017) Hyle, Emily P; Mayosi, Bongani M; Middelkoop, Keren; Mosepele, Mosepele; Martey, Emily B; Walensky, Rochelle P; Bekker, Linda‐Gail; Triant, Virginia A
    BACKGROUND: Sub-Saharan Africa (SSA) has confronted decades of the HIV epidemic with substantial improvements in access to life-saving antiretroviral therapy (ART). Now, with improved survival, people living with HIV (PLWH) are at increased risk for non-communicable diseases (NCDs), including atherosclerotic cardiovascular disease (CVD). We assessed the existing literature regarding the association of CVD outcomes and HIV in SSA. METHODS: We used the PRISMA guidelines to perform a systematic review of the published literature regarding the association of CVD and HIV in SSA with a focus on CVD surrogate and clinical outcomes in PLWH. RESULTS: From January 2000 until March 2017, 31 articles were published regarding CVD outcomes among PLWH in SSA. Data from surrogate CVD outcomes (n = 13) suggest an increased risk of CVD events among PLWH in SSA. Although acute coronary syndrome is reported infrequently in SSA among PLWH, limited data from five studies suggest extensive thrombus and hypercoagulability as contributing factors. Additional studies suggest an increased risk of stroke among PLWH (n = 13); however, most data are from immunosuppressed ART-naïve PLWH and thus are potentially confounded by the possibility of central nervous system infections. CONCLUSIONS: Given ongoing gaps in our current understanding of CVD and other NCDs in PLWH in SSA, it is imperative to ascertain the burden of CVD outcomes, and to examine strategies for intervention and best practices to enhance the health of this vulnerable population.
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    The pharmacoeconomics of routine postoperative troponin surveillance to prevent and treat myocardial infarction after non-cardiac surgery
    (2014) Torborg, Alex; Ryan, Lisa; Kantor, Gary; Biccard, Bruce M
    BACKGROUND: A postoperative troponin leak that was previously considered clinically insignificant has been independently associated with 30-day mortality in unselected surgical patients 45 years of age following non-cardiac surgery. OBJECTIVES: To determine whether routine troponin surveillance following non-cardiac surgery and initiation of aspirin and statin therapy in troponin-positive patients is cost-effective. METHODS: Pharmacoeconomic analysis to determine the cost-effectiveness of routine postoperative surveillance for patients aged 45 years undergoing non-cardiac surgery. We compared the total expected cost of hospital care of patients who received routine troponin surveillance and subsequent introduction of statin and aspirin therapy for 30 days in troponin-positive patients with the cost of hospital care of patients who did not receive troponin surveillance. We estimated a 25% relative risk reduction following statin and aspirin therapy for postoperative vascular mortality and non-fatal myocardial infarction. RESULTS: Routine troponin surveillance with initiation of aspirin and statin therapy was cost-effective, with an incremental cost of -R16 724 per event avoided. CONCLUSION: Routine postoperative troponin surveillance in non-cardiac surgical patients 45 years of age requiring a postoperative night in hospital is potentially cost-effective.
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    The targeting of nutritionally at-risk children attending a primary health care facility in the Western Cape Province of South Africa
    (2006) Schoeman, SE; Hendricks, MK; Hattingh, SP; Benadé, AJS; Laubscher, JA; Dhansay, M A
    AIM: The aim of this study was to determine the practices of primary health care (PHC) nurses in targeting nutritionally at-risk infants and children for intervention at a PHC facility in a peri-urban area of the Western Cape Province of South Africa. METHODOLOGY: Nutritional risk status of infants and children <6 years of age was based on criteria specified in standardised nutrition case management guidelines developed for PHC facilities in the province. Children were identified as being nutritionally at-risk if their weight was below the 3rd centile, their birth weight was less than 2500 g, and their growth curve showed flattening or dropping off for at least two consecutive monthly visits. The study assessed the practices of nurses in identifying children who were nutritionally at-risk and the entry of these children into the food supplementation programme (formerly the Protein-Energy Malnutrition Scheme) of the health facility. Structured interviews were conducted with nurses to determine their knowledge of the case management guidelines; interviews were also conducted with caregivers to determine their sociodemographic status. RESULTS: One hundred and thirty-four children were enrolled in the study. The mean age of their caregivers was 29.5 (standard deviation 7.5) years and only 47 (38%) were married. Of the caregivers, 77% were unemployed, 46% had poor household food security and 40% were financially dependent on non-family members. Significantly more children were nutritionally at-risk if the caregiver was unemployed (54%) compared with employed (32%) (P=0.04) and when there was household food insecurity (63%) compared with household food security (37%) (P<0.004). Significantly more children were found not to be nutritionally at-risk if the caregiver was financially self-supporting or supported by their partners (61%) compared with those who were financially dependent on non-family members (35%) (P=0.003). The weight results of the nurses and the researcher differed significantly (P<0.001), which was largely due to the different scales used and weighing methods. The researcher's weight measurements were consistently higher than the nurses' (P<0.00). The researcher identified 67 (50%) infants and children as being nutritionally at-risk compared with 14 (10%) by the nurses. The nurses' poor detection and targeting of nutritionally at-risk children were largely a result of failure to plot weights on the weight-for-age chart (55%) and poor utilisation of the Road to Health Chart. CONCLUSIONS: Problems identified in the practices of PHC nurses must be addressed in targeting children at nutritional risk so that appropriate intervention and support can be provided. More attention must be given to socio-economic criteria in identifying children who are nutritionally at-risk to ensure their access to adequate social security networks.
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    Why a management procedure approach? Some positives and negatives
    (Oxford University Press (OUP), 2007) Butterworth, Doug S
    The origin of the management procedure (MP) approach (sometimes termed management strategy evaluation), with its simulation testing of feedback-control algorithms as a necessary and structured basis for dealing with the inevitable uncertainties associated with fisheries assessments, is briefly reviewed. Also discussed are the advantages that overcome some of the difficulties of the “traditional” approach of coupling an annual “best” assessment to some harvest control rule, such as a failure to consider longer-term trade-offs properly. The MP approach does, however, also have disadvantages, such as the length of time typically required for its development and an argued inflexibility after implementation. Solutions that have been developed to overcome some of these difficulties are discussed.