SA-MRC/Wits Agincourt Unit (Research Outputs/Publications)

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    Changing Knowledge and Attitudes Towards HIV Treatment‑as‑Prevention and “Undetectable=Untransmittable”: A Systematic Review
    (2021-04-30) Jacob Bor; Charlie Fischer; Mirva Modi; Bruce Richman; Cameron Kinker; Rachel King; Sarah K. Calabrese; Idah Mokhele; Tembeka Sineke; Thembelihle Zuma; Sydney Rosen; Till Bärnighausen; Kenneth H. Mayer; Dorina Onoya2
    People on HIV treatment with undetectable virus cannot transmit HIV sexually (Undetectable=Untransmittable, U=U). However, the science of treatment-as-prevention (TasP) may not be widely understood by people with and without HIV who could beneft from this information. We systematically reviewed the global literature on knowledge and attitudes related to TasP and interventions providing TasP or U=U information. We included studies of providers, patients, and communities from all regions of the world, published 2008–2020. We screened 885 papers and abstracts and identifed 72 for inclusion. Studies in high-income settings reported high awareness of TasP but gaps in knowledge about the likelihood of transmission with undetectable HIV. Greater knowledge was associated with more positive attitudes towards TasP. Extant literature shows low awareness of TasP in Africa where 2 in 3 people with HIV live. The emerging evidence on interventions delivering information on TasP suggests benefcial impacts on knowledge, stigma, HIV testing, and viral suppression. Review was pre-registered at PROSPERO: CRD42020153725
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    Estimated effect of increased diagnosis, treatment, and control of diabetes and its associated cardiovascular risk factors among low-income and middle-income countries: a microsimulation model
    (2021-09-22) Sanjay Basu; David Flood; Pascal Geldsetzer; Michaela Theilmann; Maja E Marcus; Cara Ebert; Mary Mayige; Roy Wong-McClure; Farshad Farzadfar; Sahar Saeedi Moghaddam; Kokou Agoudavi; Bolormaa Norov; Corine Houehanou; Glennis Andall-Brereton; Mongal Gurung; Garry Brian; Pascal Bovet; Joao Martins; Rifat Atun; Till Bärnighausen; Sebastian Vollmer; Jen Manne-Goehler; Justine Davies
    Background Given the increasing prevalence of diabetes in low-income and middle-income countries (LMICs), we aimed to estimate the health and cost implications of achieving different targets for diagnosis, treatment, and control of diabetes and its associated cardiovascular risk factors among LMICs. Methods We constructed a microsimulation model to estimate disability-adjusted life-years (DALYs) lost and healthcare costs of diagnosis, treatment, and control of blood pressure, dyslipidaemia, and glycaemia among people with diabetes in LMICs. We used individual participant data—specifically from the subset of people who were defined as having any type of diabetes by WHO standards—from nationally representative, cross-sectional surveys (2006–18) spanning 15 world regions to estimate the baseline 10-year risk of atherosclerotic cardiovascular disease (defined as fatal and non-fatal myocardial infarction and stroke), heart failure (ejection fraction of <40%, with New York Heart Association class III or IV functional limitations), end-stage renal disease (defined as an estimated glomerular filtration rate <15 mL/min per 1∙73 m² or needing dialysis or transplant), retinopathy with severe vision loss (<20/200 visual acuity as measured by the Snellen chart), and neuropathy with pressure sensation loss (assessed by the Semmes-Weinstein 5∙07/10 g monofilament exam). We then used data from meta-analyses of randomised controlled trials to estimate the reduction in risk and the WHO OneHealth tool to estimate costs in reaching either 60% or 80% of diagnosis, treatment initiation, and control targets for blood pressure, dyslipidaemia, and glycaemia recommended by WHO guidelines. Costs were updated to 2020 International Dollars, and both costs and DALYs were computed over a 10-year policy planning time horizon at a 3% annual discount rate. Findings We obtained data from 23 678 people with diabetes from 67 countries. The median estimated 10-year risk was 10∙0% (IQR 4∙0–18∙0) for cardiovascular events, 7∙8% (5∙1–11∙8) for neuropathy with pressure sensation loss, 7∙2% (5∙6–9∙4) for end-stage renal disease, 6∙0% (4∙2–8∙6) for retinopathy with severe vision loss, and 2∙6% (1∙2–5∙3) for congestive heart failure. A target of 80% diagnosis, 80% treatment, and 80% control would be expected to reduce DALYs lost from diabetes complications from a median population-weighted loss to 1097 DALYs per 1000 population over 10 years (IQR 1051–1155), relative to a baseline of 1161 DALYs, primarily from reduced cardiovascular events (down from a median of 143 to 117 DALYs per 1000 population) due to blood pressure and statin treatment, with comparatively little effect from glycaemic control. The target of 80% diagnosis, 80% treatment, and 80% control would be expected to produce an overall incremental cost-effectiveness ratio of US$1362 per DALY averted (IQR 1304–1409), with the majority of decreased costs from reduced cardiovascular event management, counterbalanced by increased costs for blood pressure and statin treatment, producing an overall incremental costeffectiveness ratio of $1362 per DALY averted (IQR 1304–1409). Interpretation Reducing complications from diabetes in LMICs is likely to require a focus on scaling up blood pressure and statin medication treatment initiation and blood pressure medication titration rather than focusing on increasing screening to increase diabetes diagnosis, or a glycaemic treatment and control among people with diabetes.
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    Large age shifts in HIV-1 incidence patterns in KwaZulu-Natal, South Africa
    (2021-07-13) Adam Akullian; Alain Vandormael; Joel C Miller; Anna Bershteyn; Edward Wenger; Diego Cuadros; Dickman Gareta; Till Bärnighausen; Kobus Herbst; Frank Tanser
    Recent declines in adult HIV-1 incidence have followed the large-scale expansion of antiretroviral therapy and primary HIV prevention across high-burden communities of sub-Saharan Africa. Mathematical modeling suggests that HIV risk will decline disproportionately in younger adult age-groups as interventions scale, concentrating new HIV infections in those >age 25 over time. Yet, no empirical data exist to support these projections. We conducted a population-based cohort study over a 16-y period (2004 to 2019), spanning the early scale-up of antiretroviral therapy and voluntary medical male circumcision, to estimate changes in the age distribution of HIV incidence in a hyperepidemic region of KwaZulu-Natal, South Africa, where adult HIV incidence has recently declined. Median age of HIV seroconversion increased by 5.5 y in men and 3.0 y in women, and the age of peak HIV incidence increased by 5.0 y in men and 2.0 y in women. Incidence declined disproportionately among young men (64% in men 15 to 19, 68% in men 20 to 24, and 46% in men 25 to 29) and young women (44% in women 15 to 19, 24% in women 20 to 24) comparing periods pre- versus post-universal test and treat. Incidence was stable (<20% change) in women aged 30 to 39 and men aged 30 to 34. Age shifts in incidence occurred after 2012 and were observed earlier in men than in women. These results provide direct epidemiological evidence of the changing demographics of HIV risk in sub-Saharan Africa in the era of large-scale treatment and prevention. More attention is needed to address lagging incidence decline among older individuals.
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    The impact of retirement on inpatient healthcare utilization in Guangzhou, China: a regression discontinuity analysis of 189,031 health insurance claims
    (2022-04-29) Xintong Zhao; Yuehua Liu; Xin Zhang; Till Bärnighausen; Simiao Chen BMC Geriatrics
    Background Previous studies suggest that retirement, a major life event, affects overall healthcare utilization. We examine, the effects of retirement on inpatient healthcare utilization, including effect heterogeneity by gender, disease category, and type of health service. Methods We used routine health insurance claims data (N = 87,087) spanning the period 2021 - September 2013 from the Urban Employee Basic Medical Insurance (UEBMI), a mandatory social health insurance for working and retired employees in urban China. We applied a non-parametric fuzzy regression discontinuity design using the statutory retirement age in urban China as an exogenous instrument to measure the causal effect of retirement on six measures of inpatient healthcare utilization. Results Retirement reduced total hospital costs (-84.71 Chinese Yuan (CNY), 95% confidence interval (CI) -172.03 – 2.61), shortened length of hospital stays (-44.59, 95% CI -70.50 – -18.68), and increased hospital readmissions (0.06, 95% CI 0.00 – 0.12) and primary hospital visits (0.06, 95% CI 0.02 – 0.09) among women. Retirement did not significantly change inpatient healthcare utilization among men. The retirement effects among women varied by disease category. Specifically, retirement substantially increased hospitalizations for non-communicable diseases (NCDs), yet had only modest or no effect on hospitalizations for communicable diseases or injuries. Retirement effects among women also varied by the type of services. For relatively inexpensive services, such as nonoperative treatment, there were surges in the extensive margin (hospital readmission). For relatively expensive and invasive services, such as surgeries, retirement reduced the intensive margin (out-of-pocket expenditures and length of stay). Conclusions Retirement decreases overall use of inpatient healthcare for women. The examination on the disease-related heterogeneous effects helps with the introduction and implementation of integrated healthcare delivery and appropriate incentive schemes to encourage better use of healthcare resources among older adults.
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    The socioeconomic gradient of alcohol use: an analysis of nationally representative survey data from 55 low-income and middle-income countries
    (2022-10-22) Yuanwei Xu; Pascal Geldsetzer; Jen Manne-Goehler; Michaela Theilmann; Maja-E Marcus; Zhaxybay Zhumadilov; Sarah Quesnel-Crooks; Omar Mwalim; Sahar Saeedi Moghaddam; Sogol Koolaji; Khem B Karki; Farshad Farzadfar; Narges Ebrahimi; Albertino Damasceno; Krishna K Aryal; Kokou Agoudavi; Rifat Atun; Till Bärnighausen; Justine Davies; Lindsay M Jaacks; Sebastian Vollmer; Charlotte Probst
    Background: Alcohol is a leading risk factor for over 200 conditions and an important contributor to socioeconomic health inequalities. However, little is known about the associations between individuals' socioeconomic circumstances and alcohol consumption, especially heavy episodic drinking (HED; ≥5 drinks on one occasion) in low-income or middle-income countries. We investigated the association between individual and household level socioeconomic status, and alcohol drinking habits in these settings. Methods: In this pooled analysis of individual-level data, we used available nationally representative surveys-mainly WHO Stepwise Approach to Surveillance surveys-conducted in 55 low-income and middle-income countries between 2005 and 2017 reporting on alcohol use. Surveys from participants aged 15 years or older were included. Logistic regression models controlling for age, country, and survey year stratified by sex and country income groups were used to investigate associations between two indicators of socioeconomic status (individual educational attainment and household wealth) and alcohol use (current drinking and HED amongst current drinkers). Findings: Surveys from 336 287 participants were included in the analysis. Among males, the highest prevalence of both current drinking and HED was found in lower-middle-income countries (L-MICs; current drinking 49·9% [95% CI 48·7-51·2] and HED 63·3% [61·0-65·7]). Among females, the prevalence of current drinking was highest in upper-middle-income countries (U-MIC; 29·5% [26·1-33·2]), and the prevalence of HED was highest in low-income countries (LICs; 36·8% [33·6-40·2]). Clear gradients in the prevalence of current drinking were observed across all country income groups, with a higher prevalence among participants with high socioeconomic status. However, in U-MICs, current drinkers with low socioeconomic status were more likely to engage in HED than participants with high socioeconomic status; the opposite was observed in LICs, and no association between socioeconomic status and HED was found in L-MICs. Interpretation: The findings call for urgent alcohol control policies and interventions in LICs and L-MICs to reduce harmful HED. Moreover, alcohol control policies need to be targeted at socially disadvantaged groups in U-MICs. Funding: Deutsche Forschungsgemeinschaft and the National Center for Advancing Translational Sciences of the US National Institutes of Health.
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    Patterns of tobacco use in low and middle income countries by tobacco product and sociodemographic characteristics: nationally representative survey data from 82 countries
    (2022-07-01) Michaela Theilmann; Julia M Lemp; Volker Winkler; Jennifer Manne-Goehler; Maja E Marcus; Charlotte Probst; William A Lopez-Arboleda; Cara Ebert; Christian Bommer; Maya Mathur; Glennis Andall-Brereton; Silver K Bahendeka; Pascal Bovet; Farshad Farzadfar; Erfan Ghasemi; Mary T Mayige; Sahar Saeedi Moghaddam; Kibachio J Mwangi; Shohreh Naderimagham; Lela Sturua; Rifat Atun; Justine I Davies; Till Bärnighausen; Sebastian Vollmer; Pascal Geldsetzer
    Objectives To determine the prevalence and frequency of using any tobacco product and each of a detailed set of tobacco products, how tobacco use and frequency of use vary across countries, world regions, and World Bank country income groups, and the socioeconomic and demographic gradients of tobacco use and use frequency within countries. Design Secondary analysis of nationally representative, crosssectional, household survey data from 82 low and middle income countries collected between 1 January 2015 and 31 December 2020. Setting Population based survey data. Participants 1231068 individuals aged 15 years and older. Main outcome measures Self-reported current smoking, current daily smoking, current smokeless tobacco use, current daily smokeless tobacco use, pack years, and current use and use frequencies of each tobacco product. Products were any type of cigarette, manufactured cigarette, hand rolled cigarette, water pipe, cigar, oral snuff, nasal snuff, chewing tobacco, and betel nut (with and without tobacco). Results The smoking prevalence in the study sample was 16.5% (95% confidence interval 16.1% to 16.9%) and ranged from 1.1% (0.9% to 1.3%) in Ghana to 50.6% (45.2% to 56.1%) in Kiribati. The user prevalence of smokeless tobacco was 7.7% (7.5% to 8.0%) and prevalence was highest in Papua New Guinea (daily user prevalence of 65.4% (63.3% to 67.5%)). Although variation was wide between countries and by tobacco product, for many low and middle income countries, the highest prevalence and cigarette smoking frequency was reported in men, those with lower education, less household wealth, living in rural areas, and higher age. Co nclusions Both smoked and smokeless tobacco use and frequency of use vary widely across tobacco products in low and middle income countries. This study can inform the design and targeting of efforts to reduce tobacco use in low and middle income countries and serve as a benchmark for monitoring progress towards national and international goals.
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    Intimate partner violence among pregnant women in Kenya: forms, perpetrators and associations
    (2022) Mariella Stiller; Till Bärnighausen; Michael Lowery Wilson
    Background: Intimate Partner violence (IPV) among pregnant women is a signifcant problem of public health importance. Nevertheless, there are relatively few studies which have examined the phenomenon in sub-Saharan settings. The aim of this study was to provide an overview of the prevalence, perpetrators, and associated factors of IPV during pregnancy in Kenya. Methods: We were making use of the 2014 Kenyan Demographic and Health Survey (KDHS) data and included women and girls of reproductive age (15–49 years) who have ever been pregnant (n = 4331). A weighted sample of respondents who have experienced violence during pregnancy (n = 397) were selected for further bivariate and multivariable logistic regression analyses in order to examine the association between IPV and socio-demographic factors. Results: The prevalence of violence among pregnant women in Kenya was 9.2%, perpetrated mostly by the current husband or partner (47.6%), followed by the former husband or partner (31.5%). Physical violence was the most common (78.6%), followed by emotional (67.8%) and sexual (34.8%). Having one or two children (aOR = 0.68; CI = 0.53−0.88), having secondary or higher education (aOR = 0.53; CI = 0.40−0.69) and being 18 years and above at frst cohabitation (aOR = 0.75; CI = 0.60−0.94) and at sexual debut (aOR = 0.65; CI = 0.53−0.80) were signifcantly associated with fewer reports of violence during pregnancy. Pregnant women who were divorced, separated or widowed (aOR = 1.91; CI = 1.47−2.47), who were employed (aOR = 1.34; CI = 1.06−1.70), who had witnessed their fathers beat their mothers (aOR = 1.59; CI = 1.28−1.97) and who had primary education (aOR = 1.53; CI = 1.11−2.14) were signifcantly more likely to experience violence. Conclusions: To prevent violence among pregnant women in Kenya, training health care providers should go hand in hand with interventions sensitising and mobilising community members, both addressing the socio-demographic drivers of IPV during pregnancy and directing a particular attention to the most vulnerable ones.
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    Self-reported involvement in road traffic crashes in Kenya: A cross-sectional survey of a nationally representative sample
    (2022-09-14) Masood Ali Shaikh; Herman Lule; Till Bärnighausen; Michael Lowery Wilson
    Abstract Background: Road traffic crashes (RTCs) are a global public health burden whose resulting morbidity and mortality disproportionately impact low- and middle-income countries with stressed health systems. There is a paucity of published studies that evaluate the sociodemographic distribution of RTCs using nationally representative samples from the African region. Aim: To examine population-wide associations between sociodemographic factors and involvement in RTCs in Kenya. Methods: Data were obtained from the 2014 Kenyan Demographic Health Survey, representing all 47 counties in Kenya, from May to October of 2014. We estimated the prevalence of RTCs and utilized logistic regression for bivariate and multivariable analyses to determine the sociodemographic factors associated with RTCs. Study variables included age, place of residence, household wealth index, educational attainment, and history of alcohol consumption. We computed odds ratios (ORs) and their corresponding 95% confidence intervals (CIs). Results: A higher prevalence was reported among men (8.76%) versus women (3.22%). The risk factors among men included being 20-34 years of age, living in a rural area (OR 1.38, 95% CI 1.09, 1.74), drinking alcohol (OR 1.33, 95% CI 1.11, 1.59), and having not higher than a primary (OR 1.90, 95% CI 1.19, 3.03) or secondary (OR 1.68, 95% CI 1.04, 2.71) education. The strongest risk factors for women included the being aged 45-49 (OR 2.30, 95% CI 1.44, 3.67) and 20-24 years (OR 1.81, 95% 1.17, 2.79) as well as being in the fourth wealth quintile (OR 1.83, 95% CI 1.15, 2.91). Conclusion: Men and the most economically productive age groups were more likely to report being involved in RTCs. Strategies to reduce the occurrences of RTCs should prioritize the most vulnerable sociodemographic groups.
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    The influence of depressive symptoms and school-going status on risky behaviors: a pooled analysis among adolescents in six sub-Saharan African countries
    (2023-07-24) Uttara Partap; Nega Assefa; Yemane Berhane; Ali Sie; David Guwatudde; Japhet Killewo; Ayoade Oduola; Mary M. Sando; Said Vuai; Richard Adanu; Till Bärnighausen; Wafaie W. Fawzi
    Background Evidence from sub-Saharan Africa (SSA) regarding risky behaviors among adolescents remains scarce, despite the large population (approximately 249 million out of 1.2 billion globally in 2019) of adolescents in the region. We aimed to examine the potential influence of depressive symptoms and school-going status on risky behaviors among adolescents in six SSA countries. Methods We used individual cross-sectional data from adolescents aged 10–19 based in eight communities across six SSA countries, participating in the ARISE Network Adolescent Health Study (N = 7,661). Outcomes of interest were cigarette or tobacco use, alcohol use, other substance use, getting into a physical fight, no condom use during last sexual intercourse, and suicidal behavior. We examined the proportion of adolescents reporting these behaviors, and examined potential effects of depressive symptoms [tertiles of 6-item Kutcher Adolescent Depression Scale (KADS-6) score] and school-going status on these behaviors using mixed-effects Poisson regression models. We also assessed effect modification of associations by sex, age, and school-going status. Results The proportion of adolescents reporting risky behaviors was varied, from 2.2% for suicidal behaviors to 26.2% for getting into a physical fight. Being in the higher tertiles of KADS-6 score was associated with increased risk of almost all risky behaviors [adjusted risk ratio (RR) for highest KADS-6 tertile for alcohol use: 1.70, 95% confidence interval (95% CI): 1.48–1.95, p < 0.001; for physical fight: 1.52, 95% CI: 1.36–1.70, p < 0.001; for suicidal behavior: 7.07, 95% CI: 2.69–18.57, p < 0.001]. Being in school was associated with reduced risk of substance use (RR for alcohol use: 0.73, 95% CI: 0.53–1.00, p = 0.047), and not using a condom (RR: 0.81, 95% CI: 0.66–0.99, p = 0.040). There was evidence of modification of the effect of school-going status on risky behaviors by age and sex. Conclusion Our findings reinforce the need for a greater focus on risky behaviors among adolescents in SSA. Addressing depressive symptoms among adolescents, facilitating school attendance and using schools as platforms to improve health may help reduce risky behaviors in this population. Further research is also required to better assess the potential bidirectionality of associations.
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    The effect of population-based blood pressure screening on long-term cardiometabolic morbidity and mortality in Germany: A regression discontinuity analysis
    (2022-12-27) Sara Pedron; Michael Hanselmann; Jacob Burns; Alexander Rich; Annette Peters; Margit Heier; Lars Schwettmann; Jacob H Bor; Till Bärnighausen; Michael Laxy
    Background: Hypertension represents one of the major risk factors for cardiovascular morbidity and mortality globally. Early detection and treatment of this condition is vital to prevent complications. However, hypertension often goes undetected, and even if detected, not every patient receives adequate treatment. Identifying simple and effective interventions is therefore crucial to fight this problem and allow more patients to receive the treatment they need. Therefore, we aim at investigating the impact of a population-based blood pressure (BP) screening and the subsequent "low-threshold" information treatment on long-term cardiovascular disease (CVD) morbidity and mortality. Methods and findings: We examined the impact of a BP screening embedded in a population-based cohort study in Germany and subsequent personalized "light touch" information treatment, including a hypertension diagnosis and a recommendation to seek medical attention. We pooled four waves of the KORA study, carried out between 1984 and 1996 (N = 14,592). Using a sharp multivariate regression discontinuity (RD) design, we estimated the impact of the information treatment on CVD mortality and morbidity over 16.9 years. Additionally, we investigated potential intermediate outcomes, such as hypertension awareness, BP, and behavior after 7 years. No evidence of effect of BP screening was observed on CVD mortality (hazard ratio (HR) = 1.172 [95% confidence interval (CI): 0.725, 1.896]) or on any (fatal or nonfatal) long-term CVD event (HR = 1.022 [0.636, 1.641]) for individuals just above (versus below) the threshold for hypertension. Stratification for previous self-reported diagnosis of hypertension at baseline did not reveal any differential effect. The intermediate outcomes, including awareness of hypertension, were also unaffected by the information treatment. However, these results should be interpreted with caution since the analysis might not be sufficiently powered to detect a potential intervention effect. Conclusions: The study does not provide evidence of an effect of the assessed BP screening and subsequent information treatment on BP, health behavior, or long-term CVD mortality and morbidity. Future studies should consider larger datasets to detect possible effects and a shorter follow-up for the intermediate outcomes (i.e., BP and behavior) to detect short-, medium-, and long-term effects of the intervention along the causal pathway.