Urban African Population Research Articles

South African diabetic patients’ use of mobile applications for physical activity: An age comparison

The prevalence of diabetes is greater in older, low-income, urban South African populations. Exploring the potential of mobile applications to aid in this challenge, the research focuses on 514 diabetic patients in Cape Town, applying the Theory of Planned Behaviour. Utilizing Partial Least Squares Structural Equation Modelling, the study identifies age-specific variations in factors influencing mobile app use. While overall predictability of intention to use mobile health apps for exercise is moderate (R2 = 11.6%), specific relationships differ across age groups. Notably, relationships involving Social Norm, Intention, and Perceived Behavioural Control show insignificance in certain age brackets. Although the study retains significance for the oldest age group at a 95% confidence interval, compared to the original 99%, the overall model exhibits low predictive power. The findings underscore the necessity for designers to tailor mobile applications to diverse age requirements. This research contributes to theoretical understanding by highlighting age-related nuances in the Theory of Planned Behaviour, offering practical insights for intervention design and public health policies to enhance diabetes management among various age groups in South Africa.

Maternal weight trajectories and associations with infant growth in South African women

BackgroundDespite the close relationship between pre-pregnancy body mass index (BMI), gestational weight gain (GWG) and postpartum weight (PPW), these factors are often studied separately. There are no data characterising longitudinal weight trajectories among pregnant and postpartum women in urban African populations. We examined maternal weight trajectories from pregnancy through to 12 months postpartum, factors associated with higher weight trajectory class membership and associations of weight trajectories with infant growth at 12 months.MethodsData from 989 women were examined for weight trajectories from first antenatal care visit in pregnancy to 12 months postpartum using latent-class growth models. Baseline factors associated with class membership were assessed using multinomial logistic regression. Of the enrolled women, 613 of their infants were assessed for growth at 12 months. Anthropometry measurements for mothers and infants were conducted by a trained study nurse. Associations between maternal weight trajectory class and infant weight-for-age (WAZ), length-for-age (LAZ), weight-for-length (WLZ) at 12 months of age were analysed using linear regression.ResultsFour distinct classes of maternal weight trajectories were identified. The classes included consistent low (29%), consistent medium (37%), medium–high (24%) and consistent high (10%) trajectories. Similar to trends observed with medium–high trajectory, baseline factors positively associated with consistent high class membership included age (OR 1.05, 95% CI 1.01–1.09), pre-pregnancy BMI (OR 2.24, 95% CI 1.97–2.56), stage 1 hypertension (OR 3.28, 95% CI 1.68–6.41), haemoglobin levels (OR 1.39, 95% CI 1.11–1.74) and parity (OR 1.39, 95% CI 1.15–1.67); living with HIV (OR 0.47, 95% CI 0.30–0.74) was inversely associated. In adjusted analyses, compared to consistent medium weight trajectory, consistent low weight trajectory (mean difference -0.41, 95% CI -0.71;-0.12) was associated with decreased, and consistent high weight trajectory (mean difference 1.21, 95% CI 0.59–1.83) with increased infant WAZ at 12 months of age.ConclusionIdentification of unique longitudinal weight trajectory groupings might inform comprehensive efforts targeted at improving healthy maternal weight and infant outcomes.

African cities by 2063: Fostering theologies of urban citizenship

Grounded in a postcolonial, liberationist urban vision, this article lamented the theological and political paralysis of urban denialism that fails African cities and African urban populations. Considering different possible urban trajectories towards 2063 – ranging from floundering to flourishing, implosion to explosion, and apocalyptic disaster to complete rebirth – it then proposed theologies of African urban citizenship, as response. It sought to articulate a vision of citizen-driven African cities, remaking cities ‘from below’, through interconnected and intersectional urban movements. It considered urban citizenship not as the decent and orderly conduct of subjects of the nation-state but as the disruptive and transformative presence and participation of citizens of God’s new city, breaking into cities across the African continent. While it bemoaned the absence of ‘Africa’s urban revolution’ from mainstream theologies and politics practised in the African context, and the insufficient attention paid to it even by the Africa 2063 manifesto, it dared to evoke hope, in spite of evidence to the contrary. This should be viewed as a conceptual contribution, fusing literature study with deep urban immersion.Contribution: Grounded in a postcolonial, liberationist urban vision, this article lamented the theological and political paralysis of urban denialism that fails African cities and African urban populations, contemplating theologies of African urban citizenship instead.

Longitudinal Ambient PM2.5 Measurement at Fifteen Locations in Eight Sub-Saharan African Countries Using Low-Cost Sensors

Air pollution is a major global public health issue causing considerable morbidity and mortality. Measuring levels of air pollutants and facilitating access to the data has been identified as a pathway to raise awareness and initiate dialogue between relevant stakeholders. Low-and middle-income countries (LMICs) urgently need simple, low-cost approaches to generate such data, especially in settings with no or unreliable data. We established a network of easy-to-use low-cost air quality sensors (PurpleAir-II-SD) to monitor fine particulate matter (PM2.5) concentrations at 15 sites, in 11 cities across eight sub-Saharan Africa (sSA) countries between February 2020 and January 2021. Annual PM2.5 concentrations, seasonal and temporal variability were determined. Time trends were modelled using harmonic regression. Annual PM2.5 concentrations ranged between 10 and 116 µg/m3 across study sites, exceeding the current WHO annual mean guideline level of 5 µg/m3. The largest degree of seasonal variation was seen in Nigeria, where seven sites showed higher PM2.5 levels during the dry than during the wet season. Other countries with less pronounced dry/wet season variations were Benin (20 µg/m3 versus 5 µg/m3), Uganda (50 µg/m3 versus 45 µg/m3), Sukuta (Gambia) (20 µg/m3 versus 15 µg/m3) and Kenya (30 µg/m3 versus 25 µg/m3). Diurnal variation was observed across all sites, with two daily PM2.5 peaks at about 06:00 and 18:00 local time. We identified high levels of air pollution in the 11 African cities included in this study. This calls for effective control measures to protect the health of African urban populations. The PM2.5 peaks around ‘rush hour’ suggest traffic-related emissions should be a particular area for attention.

Obesity, hypertension, and tobacco use associated with left ventricular remodeling and hypertrophy in South African women: Birth to Twenty Plus Cohort

BackgroundLeft ventricular hypertrophy (LVH) is a marker of increased risk in developing future life-threatening cardiovascular disease (CVD), however, it is unclear how CVD risk factors, such as obesity, blood pressure (BP), and tobacco use, are associated with left ventricular (LV) remodeling and LVH in urban African populations. Therefore, we aimed to identify the prevalence of LVH as well as the health factors associated with LV remodeling and LVH, within black South African adult women and their pre-pubescent children.MethodsBlack female adults (n = 123; age: 29–68 years) and their children (n = 64; age: 4–10; 55% female) were recruited from the Birth to Twenty Plus Cohort in Soweto, South Africa. Tobacco and alcohol use, physical activity, presence of diabetes mellitus, heart disease, and medication were self-reported. Height, weight, and blood pressure were measured in triplicate to determine the prevalence of obesity and hypertension respectively. Echocardiography was used to assess LV mass at end-diastole, based on linear measurements, and indexed to body surface area to determine LVH.ResultsHypertension and obesity prevalences were 35.8% and 59.3% for adults and 45.3% and 6.3% for children. Self-reported tobacco use in adults was 22.8%. LVH prevalence was 35.8% in adults (75% eccentric: 25% concentric), and 6.3% in children. Concentric remodeling was observed in 15.4% of adults, however, concentric remodeling was only found in one child. In adults, obesity [OR: 2.54 (1.07–6.02; p = 0.02)] and hypertension [3.39 (1.08–10.62; p = 0.04)] significantly increased the odds of LVH, specifically eccentric LVH, while concentric LVH was associated with self-reported tobacco use [OR: 4.58 (1.18–17.73; p = 0.03)]. Although no logistic regression was run within children, of the four children LVH, three had elevated blood pressure and the child with normal blood pressure was overweight.ConclusionsThe association between obesity, hypertension, tobacco use, and LVH in adults, and the 6% prevalence of LVH in children, calls for stronger public health efforts to control risk factors and monitor children who are at risk.

Telemedicine Preparedness Among Older Adults With Chronic Illness: Survey of Primary Care Patients.

BackgroundOlder adults are a high priority for telemedicine given their elevated COVID-19 risk and need for frequent provider contact to manage chronic illnesses. It seems that many older adults now use smartphones but few studies have examined their overall readiness for telemedicine.ObjectiveThe aim of this study is to survey older primary care patients about their telemedicine preparedness, including internet usage, internet-capable devices, telemedicine experiences and concerns, and perceived barriers. Results were used to inform a telemedicine preparedness training program.MethodsCommunity-dwelling older adult patients (aged 65-81 years; N=30) with a chronic health condition that could be managed remotely who were present at a family medicine clinic that primarily serves an urban African American population for a prescheduled in-person appointment were asked to complete a brief survey written for this study. Data were collected February-June 2021 at a large, urban, Midwestern hospital. To minimize patient burden, the survey was limited to 10 questions, focused on the most critical topics.ResultsMost participants (21/30, 70%) reported having a device that could be used for telemedicine and using the internet. However, about half had only a single connected device, and messaging and video calling were the most commonly used applications. Few used email and none used online shopping or banking. Only 7 patients had had telemedicine appointments. Telemedicine users were younger than nonusers and used more internet functions than nonusers. Only 2 people reported problems with their telemedicine visits (technology and privacy). Nearly all respondents recognized avoiding travel and COVID-19 exposure as telemedicine benefits. The most common concerns were loss of the doctor-patient connection and inability to be examined.ConclusionsMost older adults reported having devices that could be used for telemedicine, but their internet use patterns did not confirm the adequacy of their devices or skills for telemedicine. Doctor-patient conversations could be helpful in addressing telemedicine concerns but device and skill gaps must be addressed as well.

Association of ADAM12 variants with osteoarthritis in an urban South African population

Association of ADAM12 variants with osteoarthritis in an urban South African population

W196 Weight management and perceived body weight and shape in an urban South African population

W196 Weight management and perceived body weight and shape in an urban South African population

Republication de : Allergie à l’arachide en Afrique sub-saharienne

Peanut was imported from South America into West Africa first during the XVIth century, but its culture and its use as a source of oil and proteins expanded in Africa only in the mid-XIXth century. In rural areas of sub-Saharan Africa, the extent of peanut sensitisation and clinical allergy is very low compared to populations living in Europe and the U.S.A. This could be due to the protective effect of anti-CCD IgE and IgG, which can cross-react between peanut and parasites’ carbohydrate epitopes. These anti-CCD IgE are cause of false positive results for anti-peanut IgE tests, when whole peanut extracts are used in place of non-glycosylated molecular allergens. Several studies in southern Africa have used oral food challenges and show that the low incidence of peanut allergy is limited to rural areas and do not exist among African urban populations. No influence of ethnicity was found. This suggests that environmental factors related to urban living are crucial for the incidence of peanut allergy and probably also for food allergies in general.

An Open-Source Privacy-Preserving Large-Scale Mobile Framework for Cardiovascular Health Monitoring and Intervention Planning With an Urban African American Population of Young Adults: User-Centered Design Approach.

BackgroundCardiovascular diseases (CVDs) are the leading cause of death worldwide and are increasingly affecting younger populations, particularly African Americans in the southern United States. Access to preventive and therapeutic services, biological factors, and social determinants of health (ie, structural racism, resource limitation, residential segregation, and discriminatory practices) all combine to exacerbate health inequities and their resultant disparities in morbidity and mortality. These factors manifest early in life and have been shown to impact health trajectories into adulthood. Early detection of and intervention in emerging risk offers the best hope for preventing race-based differences in adult diseases. However, young-adult populations are notoriously difficult to recruit and retain, often because of a lack of knowledge of personal risk and a low level of concern for long-term health outcomes.ObjectiveThis study aims to develop a system design for the MOYO mobile platform. Further, we seek to addresses the challenge of primordial prevention in a young, at-risk population (ie, Southern-urban African Americans).MethodsUrban African Americans, aged 18 to 29 years (n=505), participated in a series of co-design sessions to develop MOYO prototypes (ie, HealthTech Events). During the sessions, participants were orientated to the issues of CVD risk health disparities and then tasked with wireframing prototype screens depicting app features that they considered desirable. All 297 prototype screens were subsequently analyzed using NVivo 12 (QSR International), a qualitative analysis software. Using the grounded theory approach, an open-coding method was applied to a subset of data, approximately 20% (5/25), or 5 complete prototypes, to identify the dominant themes among the prototypes. To ensure intercoder reliability, 2 research team members analyzed the same subset of data.ResultsOverall, 9 dominant design requirements emerged from the qualitative analysis: customization, incentive motivation, social engagement, awareness, education, or recommendations, behavior tracking, location services, access to health professionals, data user agreements, and health assessment. This led to the development of a cross-platform app through an agile design process to collect standardized health surveys, narratives, geolocated pollution, weather, food desert exposure data, physical activity, social networks, and physiology through point-of-care devices. A Health Insurance Portability and Accountability Act–compliant cloud infrastructure was developed to collect, process, and review data, as well as generate alerts to allow automated signal processing and machine learning on the data to produce critical alerts. Integration with wearables and electronic health records via fast health care interoperability resources was implemented.ConclusionsThe MOYO mobile platform provides a comprehensive health and exposure monitoring system that allows for a broad range of compliance, from passive background monitoring to active self-reporting. These study findings support the notion that African Americans should be meaningfully involved in designing technologies that are developed to improve CVD outcomes in African American communities.

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

Hyperglycaemia first detected in pregnancy (HFDP), on the rise in urban sub-Saharan Africa (SSA), may negatively impact foetal neurodevelopment, with potential long-term cognitive consequences for the child. Data on this association from SSA is lacking, and we aimed to investigate the association in 3- to 6-year-old children in Soweto, South Africa. In this comparative study, we compared cognitive skills measured with the Herbst Early Childhood Development Criteria test in 95 children born to mothers with HFDP and 99 participants unexposed to maternal HFDP. Fine and gross motor skills were secondary outcomes. Ordinal regression analysis with known confounders was performed for children born at-term. Of children exposed to HFDP born at-term, 24.3% scored 'high' and 25.7% scored 'low' in the cognitive subsection of the test, as opposed to 37.7% and 12.9% in the HFDP-unexposed group, respectively. In ordinal regression, exposed participants had a significantly lower odds of scoring in a higher cognitive category when adjusting for maternal confounders and socio-economic status (OR 0.33, 95% CI 0.15-0.74, p = 0.007). No difference was found in gross motor development between the two groups; differences in fine motor development were attenuated after adjustment for maternal pregnancy factors and household socioeconomic status (OR 0.62, 95% CI 0.28-1.37, p = 0.239). Exposure to HFDP was negatively associated with cognitive development at preschool age. Optimising maternal (preconception) health and early childhood cognitive stimulation could help more children reach their developmental potential.

Organophosphate pesticide exposure as a risk factor for attempted suicide in Cape Town, South Africa: A case-control study

Pesticides are a commonly used agent for suicide in many Low- and Middle-Income countries (LMICs). However, accumulating evidence suggests that exposure to organophosphate (OP) pesticide may also increase the risk of suicide. We conducted a hospital-based case-control study to investigate whether prior household, garden or occupational OP exposure were associated with attempted suicide using conditional logistic regression modeling. Participants who attempted suicide with any means and were admitted to two Western Cape Province hospitals in South Africa were compared to a sample of controls matched by age, sex and time of admission with unrelated conditions, between August 2015 and August 2017. The means of attempted suicide was not recorded. OP exposure was determined by dialkyl phosphate (DAP) metabolites detected in hair and by environmental and occupational history. Approximately 85% of participants reported using pesticides in the home or garden and 15% of participants reported current or past occupational exposure while working on a farm. Attempted suicide was not associated with reported home or garden OP use (Odds ratio [OR] = 0.59, 95%CI 0.33–1.04), hair DAP metabolites (OR = 1.00, 95%CI 0.98–1.02) or current or past agricultural work (OR = 1.08, 95%CI 0.62–1.87), but was associated with hazardous drinking and unemployment with no household income. We found no evidence that attempted suicide was associated with environmental or occupational pesticide use in an urban South African population attending an emergency center.

The influence of HIV infection and antiretroviral treatment on pulmonary function in individuals in an urban setting in sub-Saharan Africa.

BackgroundWith the roll-out of antiretroviral treatment (ART), the life expectancy of people with HIV and, hence, morbidity from non-communicable diseases, including pulmonary diseases, have increased.ObjectivesThis research study aims to investigate whether HIV infection and ART use are associated with pulmonary function, given the high frequency of pulmonary infections, including tuberculosis (TB), associated with HIV.MethodAdults living with HIV (ART-naïve, on first- or second-line ART), and age and sex matched HIV-negative controls were included in a cross-sectional study in Johannesburg, South Africa. Spirometry was performed to determine lung function, measuring the forced expiratory volume in one second (FEV1), the forced vital capacity (FVC) and the FEV1/FVC ratio before (pre), and after (post), short-acting bronchodilator. The association of HIV infection and ART use with pulmonary function was analysed using linear regression models, adjusting for age, gender, body surface area (BSA), employment, education, smoking and TB.ResultsOverall, 548 participants (62% women) were included with a mean age of 38 (standard deviation [s.d.] 9.5) years. No effect of HIV or ART on post-FEV1 was observed in adjusted analysis. Additional adjustment for TB resulted in a higher post-FEV1 in participants on ART compared with HIV-negative participants, whereas TB was associated with a lower FEV1. No effect of HIV and ART on post-FEV1/FVC was observed.ConclusionHIV infection and ART use were not associated with reduced pulmonary function in this urban African population. Tuberculosis showed a mediating effect on the association between HIV, ART and pulmonary function.

If We Make It, Will They Take It? Attitudes Toward the Acceptability of Chlamydia Point-of-Care Testing Among Adolescents and Young Adults.

Adolescent women, 15 to 19 years of age, have the highest rate of Chlamydia trachomatis infection in the United States. The objective of this study was to ascertain knowledge and experience of C. trachomatis and acceptance of C. trachomatis point-of-care testing (POCT) if made available over-the-counter (OTC). Currently, there are no tests for C. trachomatis available OTC for purchase. Patients attending adolescent clinics at University Hospital of Brooklyn and Kings County Hospital received an anonymous 12-item questionnaire. Both clinics serve predominantly African and Caribbean American urban populations. Questions included demographics, sexual orientation, chlamydia knowledge, testing history, prior infection, partner notification, and acceptance of OTC POCT for C. trachomatis. Surveys from 151 patients (116 women, 35 men) aged 12 to 21 years (mean age, 17.6 years) were analyzed. Only 34 of the 151 (22.5%) respondents understood C. trachomatis transmission; 31 (20.5%) knew its complications. Sixty-seven (44.4%) would purchase an OTC test but 101 (66.8%) would pay no more than $20. All 151 patients reported that they would follow-up with doctor if positive; 143 (94.7%) would notify partners, although 5 of the 31 (16.1%) women with prior infection did not notify partners. Nearly half (44%) of adolescents in our population would be interested in using a potential OTC test for C. trachomatis. Cost was a major disincentive. Knowledge of infection remains cursory. However, those with a history of C. trachomatis infection and familiar with its complications were more interested in purchasing a home test. Although 100% of the respondents reported that they would follow-up with their physician if they tested positive, past behavior suggests that partner notification might be suboptimal.

Gut microbiome-mediated metabolism effects on immunity in rural and urban African populations

The human gut microbiota is increasingly recognized as an important factor in modulating innate and adaptive immunity through release of ligands and metabolites that translocate into circulation. Urbanizing African populations harbor large intestinal diversity due to a range of lifestyles, providing the necessary variation to gauge immunomodulatory factors. Here, we uncover a gradient of intestinal microbial compositions from rural through urban Tanzanian, towards European samples, manifested both in relative abundance and genomic variation observed in stool metagenomics. The rural population shows increased Bacteroidetes, led by Prevotella copri, but also presence of fungi. Measured ex vivo cytokine responses were significantly associated with 34 immunomodulatory microbes, which have a larger impact on circulating metabolites than non-significant microbes. Pathway effects on cytokines, notably TNF-α and IFN-γ, differential metabolome analysis and enzyme copy number enrichment converge on histidine and arginine metabolism as potential immunomodulatory pathways mediated by Bifidobacterium longum and Akkermansia muciniphila.

The structure of Brazilian Amazonian gut microbiomes in the process of urbanisation

Shifts in subsistence strategy among Native American people of the Amazon may be the cause of typically western diseases previously linked to modifications of gut microbial communities. Here, we used 16S ribosomal RNA sequencing to characterise the gut microbiome of 114 rural individuals, namely Xikrin, Suruí and Tupaiú, and urban individuals from Belém city, in the Brazilian Amazon. Our findings show the degree of potential urbanisation occurring in the gut microbiome of rural Amazonian communities characterised by the gradual loss and substitution of taxa associated with rural lifestyles, such as Treponema. Comparisons to worldwide populations indicated that Native American groups are similar to South American agricultural societies and urban groups are comparable to African urban and semi-urban populations. The transitioning profile observed among traditional populations is concerning in light of increasingly urban lifestyles. Lastly, we propose the term “tropical urban” to classify the microbiome of urban populations living in tropical zones.

Challenges in the implementation of the City of Johannesburg’s Expanded Social Package in alleviating COVID-19 induced food insecurity

Background: The coronavirus disease 2019 (COVID-19) pandemic has subjected the African urban population into abject poverty. Local government initiatives, such as the City of Johannesburg’s (CoJ) Expanded Social Package (ESP) ‘Siyasizana’ [we help each other], have been established to enhance food security amongst the city’s most vulnerable based on their level of income.Aim: This article analysed the extent to which the ESP was effective in addressing food insecurity in the wake of COVID-19.Setting: This research was descriptive and explanatory in nature that played an important role in obtaining an in-depth interpretation of the challenges of the implementation of ESP in mitigating food insecurity in the CoJ.Methods: This article utilised a qualitative case study design with the aid of existing literature, municipal documents and authoritative internet sources in order to analyse the extent to which the ESP is effective in addressing food insecurity in the wake of COVID-19.Results: This article found out that the ESP did not expressly address the COVID-19-induced food insecurity because of numerous challenges, namely awareness, stigmatisation, qualification and hidden costs.Conclusion: The CoJ should bring in private players to finance the programme as COVID-19 has increased the number of beneficiaries, relax the requirement for in-person application to allow for online registration, increase the ESP poverty threshold of R6100 to cater for those on the border of poverty and diversify its means testing to include other criteria such as Unemployment Insurance Fund (UIF), which will provide much needed relief to those who might have lost income.

Sexually transmitted infections, their treatment and urban change in colonial Leopoldville, 1910–1960

AbstractDuring the colonial period sexually transmitted infections (STIs) came to be recognised as a major public health problem in African cities. Thus, STI control and urban modernisation became deeply entangled as authorities redrew spatial and social boundaries to manage populations and their cross-cultural interaction. Public health measures, urban planning and policing were part of a coordinated effort to neutralise the potential impact of rapidly growing African urban migration on the Belgian Congo’s ‘model’ capital Leopoldville. While STI control was facilitated by new drugs (arsenicals, sulfonamides and antibiotics) to treat syphilis, chancroid, gonorrhoea and chlamydia (bacterial STIs), the effects of the 1929 economic crisis and urban social change illustrated the limits of colonial authority. Redesigning urban spaces and repressive measures to curb polygyny and prostitution operated in a parallel fashion with the expansion of health coverage, new treatments and awareness campaigns. To gain a better understanding of the evolution of STI incidence among African urban populations during the colonial period between 1910 and 1960, extensive archival records and secondary literature were consulted to assess the interplay between improved screening, diagnostic and therapeutic methods with demographic and social change. They show that STI rates, probably peaked during the pre-1929 period and apart from a short period in the early 1930s associated with mass screening, declined until becoming residual in the 1950s. Reflecting upon sanitary interventions and their broader dimensions, the article analyses the evolution of treatment regimes and their impact in the changing urban organisation and environment of the colony’s capital.

Electrocardiographic and echocardiographic abnormalities in urban African people living with HIV in South Africa.

BackgroundStudies from high income countries report that HIV-positive people have an impaired systolic and diastolic cardiac function compared to HIV-negative people. It is unclear if results can be translated directly to the Sub-Saharan Africa context. This study assesses electro- and echocardiographic characteristics in an urban African population, comparing HIV-positive people (treated and not yet treated) with HIV-negative controls.MethodsWe conducted a cross-sectional study in Johannesburg, South Africa. We enrolled HIV-positive participants from three randomized controlled trials that had recruited participants from routine HIV testing programs. HIV-negative controls were recruited from the community. Data were collected on demographics, cardiovascular risk factors, medical history and electrocardiographic and echocardiographic characteristics.ResultsIn total, 394 HIV-positive participants and 153 controls were enrolled. The mean age of HIV-positive participants was 40±9 years (controls: 35±10 years), and 34% were male (controls: 50%). Of HIV-positive participants 36% were overweight or obese (controls: 44%), 23% had hypertension (controls: 28%) and 12% were current smoker (controls: 37%). Median time since HIV diagnosis was 6.0 years (IQR 2.3–10.0) and median treatment duration was 4.0 years (IQR 0.0–8.0), 50% had undetectable viral load. The frequency of anatomical cardiac abnormalities was low and did not differ between people with and without HIV. We observed no relation between HIV or anti-retroviral therapy (ART) and systolic or diastolic heart function. There was an association between ART use and corrected QT interval: +11.8 ms compared to HIV-negative controls (p<0.01) and +18.9 ms compared to ART-naïve participants (p = 0.01). We also observed a higher left ventricular mass index in participants on ART (+7.8 g/m2, p<0.01), but this association disappeared after adjusting for CD4 cell count, viral load and HIV-duration.ConclusionThe low number of major cardiac abnormalities in this relatively young, well managed urban African HIV-positive population is reassuring. The increase in corrected QT interval and left ventricular mass may contribute to higher cardiac mortality and morbidity in people living with HIV in the long term.

Twenty four-hour urine collection is appropriate in a cohort of South African renal stone formers

Objectives: To report the prevalence of metabolic abnormalities found in an urban South African population of stone formers and thereby determine whether international guidelines on 24-hour urine collection should be recommended for South African stone formers.Methods: A retrospective folder review was conducted on patients who were admitted with renal stones or who had renal stone procedures between 1 November 2014 and 31 March 2020, with a confirmed history of renal calculi and who had 24-hour urine collection at a tertiary centre renal stone clinic. All confirmed stone formers were offered 24-hour urine collection once they were infection-free and stone-free. Demographics, 24-hour urine collection findings and stone analysis results (if available) were recorded. A 24-hour urine collection was performed once patients were stone-free while on their regular diet and routine lifestyle.Results: 175 patients with metabolic studies were included (65 females and 110 males). The mean age was 53.8 ±13.6 years. The commonest metabolic risk factors were hypocitraturia (61.0%), hypomagnesiuria (41.1%), mild hypercalciuria (22.0%), and hyperuricosuria (20.2%). Hyperuricaemia, high urinary sodium excretion, mild hypercalciuria and hyperuricosuria were more common in men. A total of 102 patients had both 24-hour urine collection and stone analysis for comparison. There were no differences between different stone types in the prevalence of metabolic risk factors except for hyperuricaemia and high urinary sodium excretion, which were both higher in uric acid predominant stone formers.Conclusion: The prevalence of risk factors was high and seemed similar to that of other populations, except for a higher prevalence of hypocitraturia. Internationally recommended guidelines for 24-hour urine studies are therefore applicable and appropriate for this population. Risk factors seem similar across stone types; however, a larger study is necessary to clarify whether metabolic risk factors are useful to predict stone composition.