Browsing by Subject "Africans"
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- ItemOpen AccessAntiretroviral therapy, especially Efavirenz, is associated with low bone mineral density in HIV-infected South Africans(Public Library of Science, 2015) Dave, Joel A; Cohen, Karen; Micklesfield, Lisa K; Maartens, Gary; Levitt, Naomi SPurpose We determined the prevalence and correlates of low bone mineral density (BMD) in HIV-infected South Africans as there is a paucity of such data from Africa. METHODS: BMD and serum 25-hydroxyvitamin D were measured in HIV-positive participants on antiretroviral therapy (ART) and in those not yet on ART (ART-naïve). RESULTS: We enrolled 444 participants [median age 35(IQR: 30, 40) years; 77% women]. BMD was low (z score <-2SD) in 17% and 5% of participants at the lumbar spine and total hip, respectively. Total hip [0.909 (SD 0.123) vs 0.956 (SD 0.124) g/cm 2 , p = 0.0001] and neck of femur BMD [0.796 (SD 0.130) vs 0.844 (SD 0.120) g/cm 2 , p = 0.0001] were lower in the ART, compared to the ART-naïve group. Vitamin D deficiency was present in 15% of participants and was associated with efavirenz use [adjusted OR 2.04 (95% CI 1.01 to 4.13)]. In a multivariate linear regression, exposure to efavirenz or lopinavir-based ART was associated with lower total hip BMD, whereas higher weight, being male and higher vitamin D concentration were associated with higher total hip BMD (adjusted R 2 = 0.28). Age, weight, sex, and the use of efavirenz-based ART were independently associated with lumbar spine BMD (adjusted R 2 = 0.13). CONCLUSIONS: Vitamin D status, use of efavirenz or lopinavir/ritonavir, weight, age and sex are significantly associated with lower BMD in this young cohort of HIV-infected South Africans.
- ItemOpen Access"Broadband" bioinformatics skills transfer with the Knowledge Transfer Programme (KTP): educational model for upliftment and sustainable development(Public Library of Science, 2015) Chimusa, Emile R; Mbiyavanga, Mamana; Masilela, Velaphi; Kumuthini, JuditA shortage of practical skills and relevant expertise is possibly the primary obstacle to social upliftment and sustainable development in Africa. The "omics" fields, especially genomics, are increasingly dependent on the effective interpretation of large and complex sets of data. Despite abundant natural resources and population sizes comparable with many first-world countries from which talent could be drawn, countries in Africa still lag far behind the rest of the world in terms of specialized skills development. Moreover, there are serious concerns about disparities between countries within the continent. The multidisciplinary nature of the bioinformatics field, coupled with rare and depleting expertise, is a critical problem for the advancement of bioinformatics in Africa. We propose a formalized matchmaking system, which is aimed at reversing this trend, by introducing the Knowledge Transfer Programme (KTP). Instead of individual researchers travelling to other labs to learn, researchers with desirable skills are invited to join African research groups for six weeks to six months. Visiting researchers or trainers will pass on their expertise to multiple people simultaneously in their local environments, thus increasing the efficiency of knowledge transference. In return, visiting researchers have the opportunity to develop professional contacts, gain industry work experience, work with novel datasets, and strengthen and support their ongoing research. The KTP develops a network with a centralized hub through which groups and individuals are put into contact with one another and exchanges are facilitated by connecting both parties with potential funding sources. This is part of the PLOS Computational Biology Education collection.
- ItemOpen AccessCardiovascular risk factors in patients with Addison's disease: a comparative study of South African and Swedish patients(Public Library of Science, 2014) Ross, Ian Louis; Bergthorsdottir, Ragnhildur; Levitt, Naomi; Dave, Joel Alex; Schatz, Desmond; Marais, David; Johannsson, GudmundurBACKGROUND: 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. METHODS: 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. RESULTS: 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/m 2 , 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. CONCLUSIONS: 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.
- ItemOpen AccessCCR2-V64I polymorphism is associated with increased risk of cervical cancer but not with HPV infection or pre-cancerous lesions in African women(BioMed Central Ltd, 2010) Chatterjee, Koushik; Dandara, Collet; Hoffman, Margaret; Williamson, Anna-LiseBACKGROUND: Cervical cancer, caused by specific oncogenic types of human papillomavirus (HPV), is the second most common cancer in women worldwide. A large number of young sexually active women get infected by HPV but only a small fraction of them have persistent infection and develop cervical cancer pointing to co- factors including host genetics that might play a role in outcome of the HPV infection. This study investigated the role of CCR2-V64I polymorphism in cervical cancer, pre-cancers and HPV infection in South African women resident in Western Cape. CCR2-V64I polymorphism has been previously reported to influence the progression to cervical cancer in some populations and has also been associated with decreased progression from HIV infection to AIDS. METHODS: Genotyping for CCR2-V64I was done by PCR-SSP in a case-control study of 446 women (106 black African and 340 mixed-ancestry) with histologically confirmed invasive cervical cancer and 1432 controls (322 black African and 1110 mixed-ancestry) group-matched (1:3) by age, ethnicity and domicile status. In the control women HPV was detected using the Digene Hybrid Capture II test and cervical disease was detected by cervical cytology. RESULTS: The CCR2-64I variant was significantly associated with cervical cancer when cases were compared to the control group (P = 0.001). Further analysis comparing selected groups within the controls showed that individuals with abnormal cytology and high grade squamous intraepitleial neoplasia (HSIL) did not have this association when compared to women with normal cytology. HPV infection also showed no association with CCR2-64I variant. Comparing SIL positive controls with the cases showed a significant association of CCR2-64I variant (P = 0.001) with cervical cancer. CONCLUSIONS: This is the first study of the role of CCR2-V64I polymorphism in cervical cancer in an African population. Our results show that CCR2-64I variant is associated with the risk of cervical cancer but does not affect the susceptibility to HPV infection or HSIL in South African women of black and mixed-ancestry origin. This result implies that the role of CCR2 is important in invasive cancer of the cervix but not in HPV infection or in the development of pre-cancers.
- ItemOpen AccessComputational analysis of candidate disease genes and variants for salt-sensitive hypertension in indigenous Southern Africans(Public Library of Science, 2010) Tiffin, Nicki; Meintjes, Ayton; Ramesar, Rajkumar; Bajic, Vladimir B.; Rayner, BrianMultiple factors underlie susceptibility to essential hypertension, including a significant genetic and ethnic component, and environmental effects. Blood pressure response of hypertensive individuals to salt is heterogeneous, but salt sensitivity appears more prevalent in people of indigenous African origin. The underlying genetics of salt-sensitive hypertension, however, are poorly understood. In this study, computational methods including text- and data-mining have been used to select and prioritize candidate aetiological genes for salt-sensitive hypertension. Additionally, we have compared allele frequencies and copy number variation for single nucleotide polymorphisms in candidate genes between indigenous Southern African and Caucasian populations, with the aim of identifying candidate genes with significant variability between the population groups: identifying genetic variability between population groups can exploit ethnic differences in disease prevalence to aid with prioritisation of good candidate genes. Our top-ranking candidate genes include parathyroid hormone precursor ( PTH ) and type-1angiotensin II receptor ( AGTR1 ). We propose that the candidate genes identified in this study warrant further investigation as potential aetiological genes for salt-sensitive hypertension.
- ItemOpen AccessThe cumulative effects of polymorphisms in the DNA mismatch repair genes and tobacco smoking in oesophageal cancer risk(Public Library of Science, 2012) Vogelsang, Matjaz; Wang, Yabing; Veber, Nika; Mwapagha, Lamech M; Parker, M IqbalThe DNA mismatch repair (MMR) enzymes repair errors in DNA that occur during normal DNA metabolism or are induced by certain cancer-contributing exposures. We assessed the association between 10 single-nucleotide polymorphisms (SNPs) in 5 MMR genes and oesophageal cancer risk in South Africans. Prior to genotyping, SNPs were selected from the HapMap database, based on their significantly different genotypic distributions between European ancestry populations and four HapMap populations of African origin. In the Mixed Ancestry group, the MSH3 rs26279 G/G versus A/A or A/G genotype was positively associated with cancer (OR = 2.71; 95% CI: 1.34-5.50). Similar associations were observed for PMS1 rs5742938 (GG versus AA or AG: OR = 1.73; 95% CI: 1.07-2.79) and MLH3 rs28756991 (AA or GA versus GG: OR = 2.07; 95% IC: 1.04-4.12). In Black individuals, however, no association between MMR polymorhisms and cancer risk was observed in individual SNP analysis. The interactions between MMR genes were evaluated using the model-based multifactor-dimensionality reduction approach, which showed a significant genetic interaction between SNPs in MSH2, MSH3 and PMS1 genes in Black and Mixed Ancestry subjects, respectively. The data also implies that pathogenesis of common polymorphisms in MMR genes is influenced by exposure to tobacco smoke. In conclusion, our findings suggest that common polymorphisms in MMR genes and/or their combined effects might be involved in the aetiology of oesophageal cancer.
- ItemOpen AccessDetermining ancestry proportions in complex admixture scenarios in South Africa using a novel proxy ancestry selection method(Public Library of Science, 2013) Chimusa, Emile R; Daya, Michelle; Möller, Marlo; Ramesar, Raj; Henn, Brenna M; van Helden, Paul D; Mulder, Nicola J; Hoal, Eileen GAdmixed populations can make an important contribution to the discovery of disease susceptibility genes if the parental populations exhibit substantial variation in susceptibility. Admixture mapping has been used successfully, but is not designed to cope with populations that have more than two or three ancestral populations. The inference of admixture proportions and local ancestry and the imputation of missing genotypes in admixed populations are crucial in both understanding variation in disease and identifying novel disease loci. These inferences make use of reference populations, and accuracy depends on the choice of ancestral populations. Using an insufficient or inaccurate ancestral panel can result in erroneously inferred ancestry and affect the detection power of GWAS and meta-analysis when using imputation. Current algorithms are inadequate for multi-way admixed populations. To address these challenges we developed PROXYANC, an approach to select the best proxy ancestral populations. From the simulation of a multi-way admixed population we demonstrate the capability and accuracy of PROXYANC and illustrate the importance of the choice of ancestry in both estimating admixture proportions and imputing missing genotypes.
- ItemOpen AccessDevelopment of a novel nutrition screening tool for use in elderly South Africans(2005) Charlton, K E; Kolbe-Alexander, T L; Nel, J HOBJECTIVE: To develop a nutrition screening tool for use in older South Africans. DESIGN: A cross-sectional validation study in 283 free-living and institutionalised black South Africans (60+ years). METHODS: Trained field-workers administered a 24-hour recall and the Mini Nutritional Assessment (MNA) screening tool, and performed anthropometric measurements and physical function tests. Cognitive function was assessed using a validated version of the Six-Item Cognitive Impairment Test. Biochemical indicators assessed included serum albumin, haemoglobin, ferritin, vitamin B12, red-blood-cell folate, cholesterol and vitamin C. The MNA was used as the gold standard against which a novel screening tool was developed using a six-step systematic approach, namely: correspondence analysis; identification of key questions; determination of internal consistency; correlational analyses with objective measures; determination of reference cut-off values for categories of nutritional risk; and determination of sensitivity and specificity. RESULTS: The new screening tool includes nine separate concepts, comprising a total of 14 questions, as well as measurement of mid-upper arm circumference. The new tool score was positively associated with level of independence in either basic activities of daily living (r = 0.472) or the more complex instrumental activities of daily living (r = 0.233). A three-category scoring system of nutritional risk was developed and shown to significantly characterise subjects according to physical function tests, level of independence and cognitive function. The new tool has good sensitivity (87.5%) and specificity (95.0%) compared with the MNA scoring system. It has a very high negative predictive value (99.5%), which means that the tool is unlikely to falsely classify subjects as well nourished/at risk when they are in fact malnourished. CONCLUSION: A novel screening tool has been shown to have content-, construct- and criterion-related validity, and the individual items have been shown to have good internal consistency. Further validation of the tool in a new population of elderly Africans is warranted.
- ItemOpen AccessDiagnostic performance of glomerular PLA2R and THSD7A antibodies in biopsy confirmed primary membranous nephropathy in South Africans(2021-01-07) Lwezaula, Bingileki F; Ameh, Oluwatoyin I; Ekrikpo, Udeme E; Botha, Francois C; Okpechi-Samuel, Ugochi S; Wearne, Nicola; Ronco, Pierre; Bello, Aminu K; Okpechi, Ikechi GBackground: Serum and tissue-based tests using phospholipase A2 receptor 1 (PLA2R) and thrombospondin type-1 domain containing 7A (THSD7A) are established immune biomarkers for the diagnosis of primary membranous nephropathy (PMN). This study assessed the diagnostic performance of these biomarkers in the diagnosis of PMN in South Africans. Methods This was a cross-sectional analysis from a single centre in Cape Town, South Africa. Relevant biodata was collected from all patients. Histology, including slides for PLA2R and THSD7A were processed and assessed by typical microscopic and immunohistochemical features. Biopsy tissues of patients with membranous lupus nephritis (LN-V) and diabetic nephropathy (DN) were used as controls. The diagnostic accuracy for diagnosis of PMN using positive PLA2R and THSD7A were evaluated. Results Of the 88 patients included, 41 had PMN with a mean age of 44.5 ± 17.5 years and 61.0% were female. Histologically, PLA2R and THSD7A were only positive in the PMN group (51.2% and 4.9%, respectively) but negative in both control groups. The sensitivity of PLA2R and THSD7A for identifying PMN was 51.2% and 4.9%, respectively. The sensitivity of both tests together was 53.7% while the specificity and positive predictive values (PPV) for any of the tests (alone or in combination) was 100%. There was no difference in the sensitivity and specificity when using PLA2R alone compared to combining the two tests (p=0.32). Conclusion Glomerular staining of PLA2R and THSD7A could have potential diagnostic values in South Africans. This has implications on how immunotherapies can be initiated and used in these settings.
- ItemOpen AccessFactors associated with excessive body fat in men and women: cross-sectional data from Black South Africans living in a rural community and an urban township(Public Library of Science, 2015) Okop, Kufre Joseph; Levitt, Naomi; Puoane, ThandiObjective To determine the factors associated with excessive body fat among black African men and women living in rural and urban communities of South Africa. METHODS: This is a cross-sectional analysis of data from the Prospective Urban and Rural Epidemiology (PURE) study, Cape Town, South Africa conducted in 2009/2010. The study sample included 1220 participants (77.2% women) aged 35-70 years, for whom anthropometric measurements were obtained and risk factors documented through face-to-face interviews using validated international PURE study protocols. Sex-specific logistic regression models were used to evaluate socio-demographic, lifestyle and psychological factors associated with three excessive body fat indicators, namely body mass index (BMI), waist circumference (WC) and body fat percent (BF%). RESULTS: The prevalence of excessive body fat based on BF%, WC and BMI cut-offs were 96.0%, 86.1%, and 81.6% for women respectively, and 62.2%, 25.9%, and 36.0% for men respectively. The significant odds of excessive body fat among the currently married compared to unmarried were 4.1 (95% CI: 1.3-12.5) for BF% and 1.9 (95% CI: 1.3-2.9) for BMI among women; and 4.9 (95% CI: 2.6-9.6), 3.2 (95% CI: 1.6-6.4) and 3.6 (95% CI: 1.9-6.8) for BF%, WC and BMI respectively among men. Age ≤50 years (compared to age >50 years) was inversely associated with excessive BF% in men and women, and less-than-a-college education was inversely associated with excessive BMI and WC in men. Tobacco smoking was inversely associated with all three excessive adiposity indicators in women but not in men. Unemployment, depression, and stress did not predict excessive body fat in men or women. CONCLUSION: The sex-differences in the socio-demographic and lifestyle factors associated with the high levels of excessive body fat in urban and rural women and men should be considered in packaging interventions to reduce obesity in these communities.
- ItemOpen AccessForced sexual experiences as risk factor for self-reported HIV infection among southern African lesbian and bisexual women(Public Library of Science, 2013) Sandfort, Theo G M; Baumann, Linda R M; Matebeni, Zethu; Reddy, Vasu; Southey-Swartz, IanEven though women who have sex with women are usually understood to be at no or very low risk for HIV infection, we explored whether lesbian and bisexual women in a geographical area with high HIV prevalence (Southern Africa) get tested for HIV and whether, among those women who get tested, there are women who live with HIV/AIDS. The study was conducted in collaboration with community-based organizations in Botswana, Namibia, South Africa and Zimbabwe. Data were collected via written surveys of women who in the preceding year had had sex with a woman (18 years and older; N = 591). Most participating women identified as lesbian and black. Almost half of the women (47.2%) reported ever having had consensual heterosexual sex. Engagement in transactional sex (lifetime) was reported by 18.6% of all women. Forced sex by men or women was reported by 31.1% of all women. A large proportion of the women reported to ever have been tested for HIV (78.3%); number of lifetime female and male partners was independently associated with having been tested; women who had engaged in transactional sex with women only or with women and men were less likely to have been tested. Self-reported HIV prevalence among tested women who knew their serostatus was 9.6%. Besides age, the sole independent predictor of a positive serostatus was having experienced forced sex by men, by women, or by both men and women. Study findings indicate that despite the image of invulnerability, HIV/AIDS is a reality for lesbian and bisexual women in Southern Africa. Surprisingly, it is not sex with men per se, but rather forced sex that is the important risk factor for self-reported HIV infection among the participating women. HIV/AIDS policy should also address the needs of lesbian, bisexual and other women who have sex with women.
- ItemOpen AccessGender differences in survival among adult patients starting antiretroviral therapy in South Africa: a multicentre cohort study(Public Library of Science, 2012) Cornell, Morna; Schomaker, Michael; Garone, Daniela Belen; Giddy, Janet; Hoffmann, Christopher J; Lessells, Richard; Maskew, Mhairi; Prozesky, Hans; Wood, Robin; Johnson, Leigh FMorna Cornell and colleagues investigate differences in mortality for HIV-positive men and women on antiretroviral therapy in South Africa.
- ItemOpen AccessGender inequitable masculinity and sexual entitlement in rape perpetration South Africa: findings of a cross-sectional study(Public Library of Science, 2011) Jewkes, Rachel; Sikweyiya, Yandisa; Morrell, Robert; Dunkle, KristinObjective To describe the prevalence and patterns of rape perpetration in a randomly selected sample of men from the general adult population, to explore factors associated with rape and to describe how men explained their acts of rape. Design Cross-sectional household study with a two- stage randomly selected sample of men. METHODS: 1737 South African men aged 18-49 completed a questionnaire administered using an Audio-enhanced Personal Digital Assistant. Multivariable logistic regression models were built to identify factors associated with rape perpetration. RESULTS: In all 27.6% (466/1686) of men had raped a woman, whether an intimate partner, stranger or acquaintance, and whether perpetrated alone or with accomplices, and 4.7% had raped in the last 12 months. First rapes for 75% were perpetrated before age 20, and 53.9% (251) of those raping, did so on multiple occasions. The logistic regression model showed that having raped was associated with greater adversity in childhood, having been raped by a man and higher maternal education. It was associated with less equitable views on gender relations, having had more partners, and many more gender inequitable practices including transactional sex and physical partner violence. Also drug use, gang membership and a higher score on the dimensions of psychopathic personality, namely blame externalisation and Machiavellian egocentricity. Asked about why they did it, the most common motivations stemmed from ideas of sexual entitlement. CONCLUSIONS: Perpetration of rape is so prevalent that population-based measures of prevention are essential to complement criminal justice system responses. Our findings show the importance of measures to build gender equity and change dominant ideas of masculinity and gender relations as part of rape prevention. Reducing men's exposure to trauma in childhood is also critically important.
- ItemOpen AccessGenetic variation in TLR genes in Ugandan and South African populations and comparison with HapMap data(Public Library of Science, 2012) Baker, Allison R; Qiu, Feiyou; Randhawa, April Kaur; Horne, David J; Adams, Mark D; Shey, Muki; Barnholtz-Sloan, Jill; Mayanja-Kizza, Harriet; Kaplan, Gilla; Hanekom, Willem A; Boom, W Henry; Hawn, Thomas R; Stein, Catherine MGenetic epidemiological studies of complex diseases often rely on data from the International HapMap Consortium for identification of single nucleotide polymorphisms (SNPs), particularly those that tag haplotypes. However, little is known about the relevance of the African populations used to collect HapMap data for study populations conducted elsewhere in Africa. Toll-like receptor (TLR) genes play a key role in susceptibility to various infectious diseases, including tuberculosis. We conducted full-exon sequencing in samples obtained from Uganda (n = 48) and South Africa (n = 48), in four genes in the TLR pathway: TLR2, TLR4, TLR6, and TIRAP. We identified one novel TIRAP SNP (with minor allele frequency [MAF] 3.2%) and a novel TLR6 SNP (MAF 8%) in the Ugandan population, and a TLR6 SNP that is unique to the South African population (MAF 14%). These SNPs were also not present in the 1000 Genomes data. Genotype and haplotype frequencies and linkage disequilibrium patterns in Uganda and South Africa were similar to African populations in the HapMap datasets. Multidimensional scaling analysis of polymorphisms in all four genes suggested broad overlap of all of the examined African populations. Based on these data, we propose that there is enough similarity among African populations represented in the HapMap database to justify initial SNP selection for genetic epidemiological studies in Uganda and South Africa. We also discovered three novel polymorphisms that appear to be population-specific and would only be detected by sequencing efforts.
- ItemOpen AccessHigh prevalence of self-reported undiagnosed HIV despite high coverage of HIV testing: a cross-sectional population based sero-survey in South Africa(Public Library of Science, 2011) Kranzer, Katharina; van Schaik, Nienke; Karmue, Unice; Middelkoop, Keren; Sebastian, Elaine; Lawn, Stephen D; Wood, Robin; Bekker, Linda-GailObjectives: To measure HIV prevalence and uptake of HIV counseling and testing (HCT) in a peri-urban South African community. To assess predictors for previous HIV testing and the association between the yield of previously undiagnosed HIV and time of last negative HIV test. METHODS: A random sample of 10% of the adult population (≥15 years) were invited to attend a mobile HCT service. Study procedures included a questionnaire, HIV testing and CD4 counts. Predictors for previous testing were determined using a binominal model. RESULTS: 1,144 (88.0%) of 1,300 randomly selected individuals participated in the study. 71.0% (68.3-73.6) had previously had an HIV test and 37.5% (34.6-40.5) had tested in the past 12 months. Men, migrants and older (>35 years) and younger (<20 years) individuals were less likely to have had a previous HIV test. Overall HIV prevalence was 22.7 (20.3-25.3) with peak prevalence of 41.8% (35.8-47.8) in women aged 25.1-35 years and 37.5% (26.7-48.3) in men aged 25.1-45 years. Prevalence of previously undiagnosed HIV was 10.3% (8.5-12.1) overall and 4.5% (2.3-6.6), 8.0% (CI 3.9-12.0) and 20.0% (13.2-26.8) in individuals who had their most recent HIV test within 1, 1-2 and more than 2 years prior to the survey. CONCLUSION: The high burden of undiagnosed HIV in individuals who had recently tested underscores the importance of frequent repeat testing at least annually. The high prevalence of previously undiagnosed HIV in individuals reporting a negative test in the 12 months preceding the survey indicates a very high incidence. Innovative prevention strategies are needed.
- ItemOpen AccessLiving on AIDS treatment: A socio-economic profile of Africans receiving Antiretroviral Therapy in Khayelitsha, Cape Town(2004) Coetzee, Celeste; Nattrass, NicoliThis paper analyses the socio-economic impact of providing antiretroviral therapy to AIDS-patients in Khayelitsha, Cape Town. The analysis employs data from a 2002 panel study of AIDS-patients receiving ARV treatment. This sample is placed within a comparative context by reporting comparable data from a 2000/1 survey of Khayelitsha. The comparative analysis shows that ARV patients suffered higher rates of ill health and experienced lower labour force participation rates than the Khayelitsha sample. Findings from the 2002 panel survey indicate that, after one year of treatment, the health status and labour force participation rate improved significantly for ARV patients.
- ItemOpen AccessMen, prostitution and the provider role: understanding the intersections of economic exchange, sex, crime and violence in South Africa(Public Library of Science, 2012) Jewkes, Rachel; Morrell, Robert; Sikweyiya, Yandisa; Dunkle, Kristin; Penn-Kekana, LovedayBACKGROUND: South African policy makers are reviewing legislation of prostitution, concerned that criminalisation hampers HIV prevention. They seek to understand the relationship between transactional sex, prostitution, and the nature of the involved men. METHODS: 1645 randomly-selected adult South African men participated in a household study, disclosing whether they had sex with a woman in prostitution or had had a provider relationship (or sex), participation in crime and violence and completing psychological measures. These became outcomes in multivariable regression models, where the former were exposure variables. RESULTS: 51% of men had had a provider relationship and expected sex in return, 3% had had sex with a woman in prostitution, 15% men had done both of these and 31% neither. Provider role men, and those who had just had sex with a woman in prostitution, were socially conservative and quite violent. Yet the men who had done both (75% of those having sex with a woman in prostitution) were significantly more misogynist, highly scoring on dimensions of psychopathy, more sexually and physically violent to women, and extensively engaged in crime. They had often bullied at school, suggesting that this instrumental, self-seeking masculinity was manifest in childhood. The men who had not engaged in sex for economic exchange expressed a much less violent, more law abiding and gender equitable masculinity; challenging assumptions about the inevitability of intersections of age, poverty, crime and misogyny. CONCLUSIONS: Provider role relationships (or sex) are normative for low income men, but not having sex with a woman in prostitution. Men who do the latter operate extensively outside the law and their violence poses a substantial threat to women. Those drafting legislation and policy on the sex industry in South Africa need to distinguish between these two groups to avoid criminalising the normal, and consider measures to protect women.
- ItemOpen AccessThe mitochondrial DNA T16189C polymorphism and HIV-associated cardiomyopathy: a genotype-phenotype association study(BioMed Central Ltd, 2009) Shaboodien, Gasnat; Engel, Mark E; Syed, Faisal; Poulton, Joanna; Badri, Motasim; Mayosi, BonganiBACKGROUND: The mitochondrial DNA (mtDNA) T16189C polymorphism, with a homopolymeric C-tract of 10-12 cytosines, is a putative genetic risk factor for idiopathic dilated cardiomyopathy in the African and British populations. We hypothesized that this variant may predispose to dilated cardiomyopathy in people who are infected with the human immunodeficiency virus (HIV). METHODS: A case-control study of 30 HIV-positive cases with dilated cardiomyopathy and 37 HIV-positive controls without dilated cardiomyopathy was conducted. The study was confined to persons of black African ancestry to minimize confounding of results by population admixture. HIV-positive patients with an echocardiographically confirmed diagnosis of dilated cardiomyopathy and HIV-positive controls with echocardiographically normal hearts were studied. Patients with secondary causes of cardiomyopathy (such as hypertension, diabetes, pregnancy, alcoholism, valvular heart disease, and opportunistic infection) were excluded from the study. DNA samples were sequenced for the mtDNA T16189C polymorphism with a homopolymeric C-tract in the forward and reverse directions on an ABI3100 sequencer. RESULTS: The cases and controls were well matched for age (median 35 years versus 34 years, P = 0.93), gender (males 60% vs 53%, P = 0.54), and stage of HIV disease (mean CD4 T cell count 260.7/muL vs. 176/muL, P = 0.21). The mtDNA T16189C variant with a homopolymeric C-tract was detected at a frequency of 26.7% (8/30) in the HIV-associated cardiomyopathy cases and 13.5% (5/37) in the HIV-positive controls. There was no significant difference between cases and controls (Odds Ratio 2.33, 95% Confidence Interval 0.67-8.06, p = 0.11). CONCLUSION: The mtDNA T16189C variant with a homopolymeric C-tract is not associated with dilated cardiomyopathy in black African people infected with HIV.
- ItemOpen AccessNot all are lost: interrupted laboratory monitoring, early death, and loss to follow-up (LTFU) in a large South African treatment program(Public Library of Science, 2012) Ahonkhai, Aima A; Noubary, Farzad; Munro, Alison; Stark, Ruth; Wilke, Marisa; Freedberg, Kenneth A; Wood, Robin; Losina, ElenaBACKGROUND: Many HIV treatment programs in resource-limited settings are plagued by high rates of loss to follow-up (LTFU). Most studies have not distinguished between those who briefly interrupt, but return to care, and those more chronically lost to follow-up. METHODS: We conducted a retrospective cohort study of 11,397 adults initiating antiretroviral therapy (ART) in 71 Southern African Catholic Bishops Conference/Catholic Relief Services HIV treatment clinics between January 2004 and December 2008. We distinguished among patients with early death, within the first 7 months on ART; patients with interruptions in laboratory monitoring (ILM), defined as missing visits in the first 7 months on ART, but returning to care by 12 months; and those LTFU, defined as missing all follow-up visits in the first 12 months on ART. We used multilevel logistic regression models to determine patient and clinic-level characteristics associated with these outcomes. RESULTS: In the first year on ART, 60% of patients remained in care, 30% missed laboratory visits, and 10% suffered early death. Of the 3,194 patients who missed laboratory visits, 40% had ILM, resuming care by 12 months. After 12 months on ART, patients with ILM had a 30% increase in detectable viremia compared to those who remained in care. Risk of LTFU decreased with increasing enrollment year, and was lowest for patients who enrolled in 2008 compared to 2004 [OR 0.49, 95%CI 0.39-0.62]. CONCLUSIONS: In a large community-based cohort in South Africa, nearly 30% of patients miss follow-up visits for CD4 monitoring in the first year after starting ART. Of those, 40% have ILM but return to clinic with worse virologic outcomes than those who remain in care. The risk of chronic LTFU decreased with enrollment year. As ART availability increases, interruptions in care may become more common, and should be accounted for in addressing program LTFU.
- ItemOpen AccessOptimal waist-to-height ratio values for cardiometabolic risk screening in an ethnically diverse sample of South African urban and rural school boys and girls(Public Library of Science, 2013) Matsha, Tandi E; Kengne, Andre-Pascal; Yako, Yandiswa Y; Hon, Gloudina M; Hassan, Mogamat S; Erasmus, Rajiv TBACKGROUND: The proposed waist-to-height ratio (WHtR) cut-off of 0.5 is less optimal for cardiometabolic risk screening in children in many settings. The purpose of this study was to determine the optimal WHtR for children from South Africa, and investigate variations by gender, ethnicity and residence in the achieved value. METHODS: Metabolic syndrome (MetS) components were measured in 1272 randomly selected learners, aged 10-16 years, comprising of 446 black Africans, 696 mixed-ancestry and 130 Caucasians. The Youden's index and the closest-top-left (CTL) point approaches were used to derive WHtR cut-offs for diagnosing any two MetS components, excluding the waist circumference. RESULTS: The two approaches yielded similar cut-off in girls, 0.465 (sensitivity 50.0, specificity 69.5), but two different values in boys, 0.455 (42.9, 88.4) and 0.425 (60.3, 67.7) based on the Youden's index and the CTL point, respectively. Furthermore, WHtR cut-off values derived differed substantially amongst the regions and ethnic groups investigated, whereby the highest cut-off was observed in semi-rural and white children, respectively, Youden's index0.505 (31.6, 87.1) and CTL point 0.475 (44.4, 75.9). CONCLUSION: The WHtR cut-off of 0.5 is less accurate for screening cardiovascular risk in South African children. The optimal value in this setting is likely gender and ethnicity-specific and sensitive to urbanization.