Browsing by Subject "Meta-analysis"

Now showing 1 - 18 of 18
  • Thumbnail Image
    Item
    Open Access
    A systematic review of the epidemiology of hepatitis A in Africa
    (2019-07-22) Patterson, Jenna; Abdullahi, Leila; Hussey, Gregory D; Muloiwa, Rudzani; Kagina, Benjamin M
    Abstract Background Hepatitis A, caused by the hepatitis A virus (HAV), is a vaccine preventable disease. In Low and Middle-Income Countries (LMICs), poor hygiene and sanitation conditions are the main risk factors contributing to HAV infection. There have been, however, notable improvements in hygiene and sanitation conditions in many LMICs. As a result, there are studies showing a possible transition of some LMICs from high to intermediate HAV endemicity. The World Health Organization (WHO) recommends that countries should routinely collect, analyse and review local factors (including disease burden) to guide the development of hepatitis A vaccination programs. Up-to-date information on hepatitis A burden is, therefore, critical in aiding the development of country-specific recommendations on hepatitis A vaccination. Methods We conducted a systematic review to present an up-to-date, comprehensive synthesis of hepatitis A epidemiological data in Africa. Results The main results of this review include: 1) the reported HAV seroprevalence data suggests that Africa, as a whole, should not be considered as a high HAV endemic region; 2) the IgM anti-HAV seroprevalence data showed similar risk of acute hepatitis A infection among all age-groups; 3) South Africa could be experiencing a possible transition from high to intermediate HAV endemicity. The results of this review should be interpreted with caution as the reported data represents research work with significant sociocultural, economic and environmental diversity from 13 out of 54 African countries. Conclusions Our findings show that priority should be given to collecting HAV seroprevalence data and re-assessing the current hepatitis A control strategies in Africa to prevent future disease outbreaks.
  • Thumbnail Image
    Item
    Open Access
    Antiretroviral therapy for prevention of tuberculosis in adults with HIV: a systematic review and meta-analysis
    (Public Library of Science, 2012) Suthar, Amitabh B; Lawn, Stephen D; Del Amo, Julia; Getahun, Haileyesus; Dye, Christopher; Sculier, Delphine; Sterling, Timothy R; Chaisson, Richard E; Williams, Brian G; Harries, Anthony D
    In a systematic review and meta-analysis, Amitabh Suthar and colleagues investigate the association between antiretroviral therapy and the reduction in the incidence of tuberculosis in adults with HIV infection.
  • Thumbnail Image
    Item
    Open Access
    Development of a standardized screening rule for tuberculosis in people living with HIV in resource-constrained settings: individual participant data meta-analysis of observational studies
    (Public Library of Science, 2011) Getahun, Haileyesus; Kittikraisak, Wanitchaya; Heilig, Charles M; Corbett, Elizabeth L; Ayles, Helen; Cain, Kevin P; Grant, Alison D; Churchyard, Gavin J; Kimerling, Michael; Shah, Sarita
    Haileyesus Getahun and colleagues report the development of a simple, standardized tuberculosis (TB) screening rule for resource-constrained settings, to identify people living with HIV who need further investigation for TB disease.
  • Thumbnail Image
    Item
    Open Access
    The Effect of Sodium Alginate and Pectin Added to a Carbohydrate Beverage on Endurance Performance, Substrate Oxidation and Blood Glucose Concentration: A Systematic Review and Meta-analysis
    (2022-06-21) Sutehall, Shaun; Muniz-Pardos, Borja; Bosch, Andrew; Pitsiladis, Yannis
    Introduction Scientific and public interest in the potential ergogenic effects of sodium alginate added to a carbohydrate (CHO) beverage has increased in the last ~ 5 years. Despite an extensive use of this technology by elite athletes and recent research into the potential effects, there has been no meta-analysis to objectively elucidate the effects of adding sodium alginate to a CHO beverage on parameters relevant to exercise performance and to highlight gaps in the literature. Methods Three literature databases were systematically searched for studies investigating the effects of sodium alginate added to CHO beverage during prolonged, endurance exercise in healthy athletes. For the systematic review, the PROSPERO guidelines were followed, and risk assessment was made using the Cochrane collaboration’s tool for assessing the risk of bias. Additionally, a random-effects meta-analysis model was used to determine the standardised mean difference between a CHO beverage containing sodium alginate and an isocaloric control for performance, whole-body CHO oxidation and blood glucose concentration. Results Ten studies were reviewed systematically, of which seven were included within the meta-analysis. For each variable, there was homogeneity between studies for performance (n = 5 studies; I2 = 0%), CHO oxidation (n = 7 studies; I2 = 0%) and blood glucose concentration (n = 7 studies; I2 = 0%). When compared with an isocaloric control, the meta-analysis demonstrated that there is no difference in performance (Z = 0.54, p = 0.59), CHO oxidation (Z = 0.34, p = 0.71) and blood glucose concentration (Z = 0.44, p = 0.66) when ingesting a CHO beverage containing sodium alginate. The systematic review revealed that several of the included studies did not use sufficient exercise intensity to elicit significant gastrointestinal disturbances or demonstrate any ergogenic benefit of CHO ingestion. Risk of bias was generally low across the included studies. Conclusions This systematic review and meta-analysis demonstrate that the current literature indicates no benefit of adding sodium alginate to a CHO beverage during exercise. Further research is required, however, before firm conclusions are drawn considering the range of exercise intensities, feeding rates and the apparent lack of benefit of CHO reported in the current literature investigating sodium alginate.
  • Thumbnail Image
    Item
    Open Access
    Epidemiology of histologically proven Glomerulonephritis in Africa: A systematic review and meta-analysis
    (Public Library of Science, 2016) Okpechi, Ikechi G; Ameh, Oluwatoyin I; Bello, Aminu K; Ronco, Pierre; Swanepoel, Charles R; Kengne, Andre P
    Background and aim: Glomerulonephritis (GN) is a leading cause of end-stage renal disease (ESRD) in Africa. Data on epidemiology and outcomes of glomerular diseases from Africa is still limited. We conducted a systematic review on the epidemiology of histologically proven glomerular diseases in Africa between 1980 and 2014. Materials and methods We searched literature using PubMed, AfricaWide, the Cumulative Index to Nursing and Allied Health Literature on EBSCO Host, Scopus, African Journals online databases, and the African Index Medicus, for relevant studies. The review was conducted using standard methods and frameworks using only biopsy-confirmed data. RESULTS: Twenty four (24) studies comprising 12,093 reported biopsies from 13 countries were included in this analysis. The median number of biopsies per study was 127.0 (50-4436), most of the studies (70.0%) originated from North Africa and the number of performed kidney biopsies varied from 5.2 to 617 biopsies/year. Nephrotic syndrome was the commonest indication of renal biopsy. The frequency of reported primary pathologic patterns included, minimal change disease (MCD); 16.5% (95%CI: 11.2-22.6), focal segmental glomerulosclerosis (FSGS); 15.9% (11.3-21.1), mesangiocapillary GN (MCGN); 11.8% (9.2-14.6), crescentic GN; 2.0% (0.9-3.5) and IgA nephropathy 2.8% (1.3-4.9). Glomerular diseases related to hepatitis B and systemic lupus erythematosus had the highest prevalence among assessed secondary diseases: 8.4% (2.0-18.4) and 7.7% (4.5-11.7) respectively. There was no evidence of publication bias and regional differences were seen mostly for secondary GNs. CONCLUSIONS: Glomerular diseases remain poorly characterized in sub-Saharan Africa due to declining renal biopsy rates and consequent paucity of data on pathologic patterns of key renal diseases. Development of renal biopsy registries in Africa is likely to enable adequate characterization of the prevalence and patterns of glomerular diseases; this could have a positive impact on chronic kidney disease evaluation and treatment in the African continent since most glomerulopathies are amenable to treatment.
  • Thumbnail Image
    Item
    Open Access
    Gametocyte carriage in uncomplicated Plasmodium falciparum malaria following treatment with artemisinin combination therapy: a systematic review and meta-analysis of individual patient data
    (2016)
    : Gametocytes are responsible for transmission of malaria from human to mosquito. Artemisinin combination therapy (ACT) reduces post-treatment gametocyte carriage, dependent upon host, parasite and pharmacodynamic factors. The gametocytocidal properties of antimalarial drugs are important for malaria elimination efforts. An individual patient clinical data meta-analysis was undertaken to identify the determinants of gametocyte carriage and the comparative effects of four ACTs: artemether-lumefantrine (AL), artesunate/amodiaquine (AS-AQ), artesunate/mefloquine (AS-MQ), and dihydroartemisinin-piperaquine (DP). : Factors associated with gametocytaemia prior to, and following, ACT treatment were identified in multivariable logistic or Cox regression analysis with random effects. All relevant studies were identified through a systematic review of PubMed. Risk of bias was evaluated based on study design, methodology, and missing data. : The systematic review identified 169 published and 9 unpublished studies, 126 of which were shared with the WorldWide Antimalarial Resistance Network (WWARN) and 121 trials including 48,840 patients were included in the analysis. Prevalence of gametocytaemia by microscopy at enrolment was 12.1 % (5887/48,589), and increased with decreasing age, decreasing asexual parasite density and decreasing haemoglobin concentration, and was higher in patients without fever at presentation. After ACT treatment, gametocytaemia appeared in 1.9 % (95 % CI, 1.7-2.1) of patients. The appearance of gametocytaemia was lowest after AS-MQ and AL and significantly higher after DP (adjusted hazard ratio (AHR), 2.03; 95 % CI, 1.24-3.12; P = 0.005 compared to AL) and AS-AQ fixed dose combination (FDC) (AHR, 4.01; 95 % CI, 2.40-6.72; P < 0.001 compared to AL). Among individuals who had gametocytaemia before treatment, gametocytaemia clearance was significantly faster with AS-MQ (AHR, 1.26; 95 % CI, 1.00-1.60; P = 0.054) and slower with DP (AHR, 0.74; 95 % CI, 0.63-0.88; P = 0.001) compared to AL. Both recrudescent (adjusted odds ratio (AOR), 9.05; 95 % CI, 3.74-21.90; P < 0.001) and new (AOR, 3.03; 95 % CI, 1.66-5.54; P < 0.001) infections with asexual-stage parasites were strongly associated with development of gametocytaemia after day 7. : AS-MQ and AL are more effective than DP and AS-AQ FDC in preventing gametocytaemia shortly after treatment, suggesting that the non-artemisinin partner drug or the timing of artemisinin dosing are important determinants of post-treatment gametocyte dynamics.
  • Thumbnail Image
    Item
    Open Access
    Genetic susceptibility to acute rheumatic fever: a systematic review and meta-analysis of twin studies
    (Public Library of Science, 2011) Engel, Mark E; Stander, Raphaella; Vogel, Jonathan; Adeyemo, Adebowale A; Mayosi, Bongani M
    BACKGROUND: Acute rheumatic fever is considered to be a heritable condition, but the magnitude of the genetic effect is unknown. The objective of this study was to conduct a systematic review and meta-analysis of twin studies of concordance of acute rheumatic fever in order to derive quantitative estimates of the size of the genetic effect. METHODS: We searched PubMed/MEDLINE, ISI Web of Science, EMBASE, and Google Scholar from their inception to 31 January 2011, and bibliographies of retrieved articles, for twin studies of the concordance for acute rheumatic fever or rheumatic heart disease in monozygotic versus dizygotic twins that used accepted diagnostic criteria for acute rheumatic fever and zygosity without age, gender or language restrictions. Twin similarity was measured by probandwise concordance rate and odds ratio (OR), and aggregate probandwise concordance risk was calculated by combining raw data from each study. ORs from separate studies were combined by random-effects meta-analysis to evaluate association between zygosity status and concordance. Heritability was estimated by fitting a variance components model to the data. RESULTS: 435 twin pairs from six independent studies met the inclusion criteria. The pooled probandwise concordance risk for acute rheumatic fever was 44% in monozygotic twins and 12% in dizygotic twins, and the association between zygosity and concordance was strong (OR 6.39; 95% confidence interval, 3.39 to 12.06; P<0.001), with no significant study heterogeneity (P = 0.768). The estimated heritability across all the studies was 60%. CONCLUSIONS: Acute rheumatic fever is an autoimmune disorder with a high heritability. The discovery of all genetic susceptibility loci through whole genome scanning may provide a clinically useful genetic risk prediction tool for acute rheumatic fever and its sequel, rheumatic heart disease.
  • Thumbnail Image
    Item
    Open Access
    HHV-8 seroprevalence: a global view
    (BioMed Central Ltd, 2014) Rohner, Eliane; Wyss, Natascha; Trelle, Sven; Mbulaiteye, Sam; Egger, Matthias; Novak, Urban; Zwahlen, Marcel; Bohlius, Julia
    BACKGROUND: Human herpes virus 8 (HHV-8) is the underlying infectious cause of Kaposi sarcoma (KS) and other proliferative diseases; that is, primary effusion lymphoma and multicentric Castleman disease. In regions with high HHV-8 seroprevalence in the general population, KS accounts for a major burden of disease. Outside these endemic regions, HHV-8 prevalence is high in men who have sex with men (MSM) and in migrants from endemic regions. We aim to conduct a systematic literature review and meta-analysis in order 1) to define the global distribution of HHV-8 seroprevalence (primary objective) and 2) to identify risk factors for HHV-8 infection, with a focus on HIV status (secondary objective).METHODS/DESIGN:We will include observational studies reporting data on seroprevalence of HHV-8 in children and/or adults from any region in the world. Case reports and case series as well as any studies with fewer than 50 participants will be excluded. We will search MEDLINE, EMBASE, and relevant conference proceedings without language restriction. Two reviewers will independently screen the identified studies and extract data on study characteristics and quality, study population, risk factors, and reported outcomes, using a standardized form. For the primary objective we will pool the data using a fully bayesian approach for meta-analysis, with random effects at the study level. For the secondary objective (association of HIV and HHV-8) we aim to pool odds ratios for the association of HIV and HHV-8 using a fully bayesian approach for meta-analysis, with random effects at the study level. Sub-group analyses and meta-regression analyses will be used to explore sources of heterogeneity, including factors such as geographical region, calendar years of recruitment, age, gender, ethnicity, socioeconomic status, different risk groups for sexually and parenterally transmitted infections (MSM, sex workers, hemophiliacs, intravenous drug users), comorbidities such as organ transplantation and malaria, test(s) used to measure HHV-8 infection, study design, and study quality.DISCUSSION:Using the proposed systematic review and meta-analysis, we aim to better define the global seroprevalence of HHV-8 and its associated risk factors. This will improve the current understanding of HHV-8 epidemiology, and could suggest measures to prevent HHV-8 infection and to reduce its associated cancer burden.
  • Thumbnail Image
    Item
    Open Access
    Hormonal contraception and the risk of HIV acquisition: an individual participant data meta-analysis
    (Public Library of Science, 2015) Morrison, Charles S; Chen, Pai-Lien; Kwok, Cynthia; Baeten, Jared M; Brown, Joelle; Crook, Angela M; Van Damme, Lut; Delany-Moretlwe, Sinead; Francis, Suzanna C; Friedland, Barbara A
    In a meta-analysis of individual participant data, Charles Morrison and colleagues explore the association between hormonal contraception use and risk of HIV infection in sub-Saharan Africa.
  • Thumbnail Image
    Item
    Open Access
    Intravaginal practices, bacterial vaginosis, and HIV infection in women: individual participant data meta-analysis
    (Public Library of Science, 2011) Low, Nicola; Chersich, Matthew F; Schmidlin, Kurt; Egger, Matthias; Francis, Suzanna C; Van de Wijgert, Janneke H H M; Hayes, Richard J; Baeten, Jared M; Brown, Joelle; Delany-Moretlwe, Sinead
    Pooling of data from 14,874 women in an individual participant data meta-analysis by Nicola Low and colleagues reveals that some intravaginal practices increase the risk of HIV acquisition.
  • Thumbnail Image
    Item
    Open Access
    A meta-analysis of the Metabolic Syndrome prevalence in the global HIV-infected population
    (Public Library of Science, 2016) Nguyen, Kim A; Peer, Nasheeta; Mills, Edward J; Kengne, Andre P
    BACKGROUND: Cardio-metabolic risk factors are of increasing concern in HIV-infected individuals, particularly with the advent of antiretroviral therapy (ART) and the subsequent rise in longevity. However, the prevalence of cardio-metabolic abnormalities in this population and the differential contribution, if any, of HIV specific factors to their distribution, are poorly understood. Therefore, we conducted a systematic review and meta-analysis to estimate the global prevalence of metabolic syndrome (MS) in HIV-infected populations, its variation by the different diagnostic criteria, severity of HIV infection, ART used and other major predictive characteristics. METHODS: We performed a comprehensive search on major databases for original research articles published between 1998 and 2015. The pooled overall prevalence as well as by specific groups and subgroups were computed using random effects models. RESULTS: A total of 65 studies across five continents comprising 55094 HIV-infected participants aged 17-73 years (median age 41 years) were included in the final meta-analysis. The overall prevalence of MS according to the following criteria were: ATPIII-2001:16.7% (95%CI: 14.6-18.8), IDF-2005: 18% (95%CI: 14.0-22.4), ATPIII-2004-2005: 24.6% (95%CI: 20.6-28.8), Modified ATPIII-2005: 27.9% (95%CI: 6.7-56.5), JIS-2009: 29.6% (95%CI: 22.9-36.8), and EGIR: 31.3% (95%CI: 26.8-36.0). By some MS criteria, the prevalence was significantly higher in women than in men (IDF-2005: 23.2% vs. 13.4, p = 0.030), in ART compared to non-ART users (ATPIII-2001: 18.4% vs. 11.8%, p = 0.001), and varied significantly by participant age, duration of HIV diagnosis, severity of infection, non-nucleoside reverse transcriptase inhibitors (NNRTIs) use and date of study publication. Across criteria, there were significant differences in MS prevalence by sub-groups such as in men, the Americas, older publications, regional studies, younger adults, smokers, ART-naïve participants, NNRTIs users, participants with shorter duration of diagnosed infection and across the spectrum of HIV severity. Substantial heterogeneities across and within criteria were not fully explained by major study characteristics, while evidence of publication bias was marginal. CONCLUSIONS: The similar range of MS prevalence in the HIV-infected and general populations highlights the common drivers of this condition. Thus, cardio-metabolic assessments need to be routinely included in the holistic management of the HIV-infected individual. Management strategies recommended for MS in the general population will likely provide similar benefits in the HIV-infected.
  • Thumbnail Image
    Item
    Open Access
    Mupirocin-resistant Staphylococcus aureus in Africa: a systematic review and meta-analysis
    (BioMed Central, 2018-08-15) Shittu, Adebayo O; Kaba, Mamadou; Abdulgader, Shima M; Ajao, Yewande O; Abiola, Mujibat O; Olatimehin, Ayodele O
    Background Mupirocin is widely used for nasal decolonization of Staphylococcus aureus to prevent subsequent staphylococcal infection in patients and healthcare personnel. However, the prolonged and unrestricted use has led to the emergence of mupirocin-resistant (mupR) S. aureus. The aim of this systematic review was to investigate the prevalence, phenotypic and molecular characteristics, and geographic spread of mupR S. aureus in Africa. Methods We examined five electronic databases (EBSCOhost, Google Scholar, ISI Web of Science, MEDLINE, and Scopus) for relevant English articles on screening for mupR S. aureus from various samples in Africa. In addition, we performed random effects meta-analysis of proportions to determine the pooled prevalence of mupR S. aureus in Africa. The search was conducted until 3 August 2016. Results We identified 43 eligible studies of which 11 (26%) were obtained only through Google Scholar. Most of the eligible studies (28/43; 65%) were conducted in Nigeria (10/43; 23%), Egypt (7/43; 16%), South Africa (6/43; 14%) and Tunisia (5/43; 12%). Overall, screening for mupR S. aureus was described in only 12 of 54 (22%) African countries. The disk diffusion method was the widely used technique (67%; 29/43) for the detection of mupR S. aureus in Africa. The mupA-positive S. aureus isolates were identified in five studies conducted in Egypt (n = 2), South Africa (n = 2), and Nigeria (n = 1). Low-level resistance (LmupR) and high-level resistance (HmupR) were both reported in six human studies from South Africa (n = 3), Egypt (n = 2) and Libya (n = 1). Data on mupR-MRSA was available in 11 studies from five countries, including Egypt, Ghana, Libya, Nigeria and South Africa. The pooled prevalence (based on 11 human studies) of mupR S. aureus in Africa was 14% (95% CI =6.8 to 23.2%). The proportion of mupA-positive S. aureus in Africa ranged between 0.5 and 8%. Furthermore, the frequency of S. aureus isolates that exhibited LmupR, HmupR and mupR-MRSA in Africa were 4 and 47%, 0.5 and 38%, 5 and 50%, respectively. Conclusions The prevalence of mupR S. aureus in Africa (14%) is worrisome and there is a need for data on administration and use of mupirocin. The disk diffusion method which is widely utilized in Africa could be an important method for the screening and identification of mupR S. aureus. Moreover, we advocate for surveillance studies with appropriate guidelines for screening mupR S. aureus in Africa.
  • Thumbnail Image
    Item
    Open Access
    Outcomes for efavirenz versus nevirapine-containing regimens for treatment of HIV-1 infection: a systematic review and meta-analysis
    (Public Library of Science, 2013) Pillay, Prinitha; Ford, Nathan; Shubber, Zara; Ferrand, Rashida A
    Introduction There is conflicting evidence and practice regarding the use of the non-nucleoside reverse transcriptase inhibitors (NNRTI) efavirenz (EFV) and nevirapine (NVP) in first-line antiretroviral therapy (ART). METHODS: We systematically reviewed virological outcomes in HIV-1 infected, treatment-naive patients on regimens containing EFV versus NVP from randomised trials and observational cohort studies. Data sources include PubMed, Embase, the Cochrane Central Register of Controlled Trials and conference proceedings of the International AIDS Society, Conference on Retroviruses and Opportunistic Infections, between 1996 to May 2013. Relative risks (RR) and 95% confidence intervals were synthesized using random-effects meta-analysis. Heterogeneity was assessed using the I 2 statistic, and subgroup analyses performed to assess the potential influence of study design, duration of follow up, location, and tuberculosis treatment. Sensitivity analyses explored the potential influence of different dosages of NVP and different viral load thresholds. RESULTS: Of 5011 citations retrieved, 38 reports of studies comprising 114 391 patients were included for review. EFV was significantly less likely than NVP to lead to virologic failure in both trials (RR 0.85 [0.73-0.99] I 2  = 0%) and observational studies (RR 0.65 [0.59-0.71] I 2  = 54%). EFV was more likely to achieve virologic success than NVP, though marginally significant, in both randomised controlled trials (RR 1.04 [1.00-1.08] I 2  = 0%) and observational studies (RR 1.06 [1.00-1.12] I 2  = 68%). CONCLUSION: EFV-based first line ART is significantly less likely to lead to virologic failure compared to NVP-based ART. This finding supports the use of EFV as the preferred NNRTI in first-line treatment regimen for HIV treatment, particularly in resource limited settings.
  • Thumbnail Image
    Item
    Restricted
    Practical application of meta-analysis results: avoiding the double use of data
    (NRC Research Press, 2005) Minte-Vera, C V; Branch, Trevor A; Stewart, I J; Dorn, M W
    Meta-analysis is an important new tool for synthesizing scientific knowledge from many previous studies. In fisheries, meta-analyses can be used to obtain prior distributions or penalty functions for parameters used in stock assessment models. Two types of results are generally published in a meta-analysis: Type A, the updated results for each stock used in the meta-analysis, and Type B, the results that would best describe a new stock. Including these results in assessments for the individual stocks would result in double use of the data if the assessments include the input data used in the meta-analyses, which they typically would. To solve this problem, we recommend that an additional form of results should be reported in meta-analyses: Type C, the results for a new stock obtained by sequentially excluding each stock's data set and repeating the meta-analysis. Type C results should be used whenever the assessment input data overlap with the meta-analysis input data, avoiding the double use of data. We illustrate the impact of this reporting change on the results of a recent meta-analysis.
  • Thumbnail Image
    Item
    Open Access
    Prevalence and etiologies of pulmonary hypertension in Africa: a systematic review and meta-analysis
    (2017) Bigna, Jean Joël; Noubiap, Jean Jacques; Nansseu, Jobert Richie; Aminde, Leopold Ndemnge
    BACKGROUND: Despite the recent increasing worldwide attention towards pulmonary hypertension (PH), its epidemiology remains poorly described in Africa. Accordingly, we performed a systematic review and meta-analysis of PH prevalence, incidence and etiologies in Africa. METHODS: We searched PubMed, EMBASE, African Journals Online, and Africa Index Medicus. Published observational studies until September 20, 2017, including adult participants residing in Africa were considered. Two review authors independently selected studies, assessed included studies for methodological quality, and extracted data. A random-effects model was used for meta-analysis. Heterogeneity was evaluated by the χ 2 test on Cochrane's Q statistic which is quantified by I2 values. Using Newcastle-Ottawa Scale, we considered a score of 0-4, 5-7, and 8-10 as indicative of high, moderate, and low risk of bias in included studies, respectively. RESULTS: Of 1611 entries, 25 studies were retained. Twelve (48%), seven (28%), and six (24%) papers had respectively a low, moderate and high risk of bias. The prevalence of PH widely varied across different populations: 9.8% (95% confidence interval: 3.2-19.3; I2 = 99.4%; 6 studies) in 11,163 people presenting with cardiac complaints; 10.6% (4.3-19.1; I2 = 90.3%; 4 studies) in 937 HIV-infected people; 32.9% (17.6-50.4; I2 = 97.2%; 3 studies) in 2077 patients with heart failure; 23.2% (15.2-32.2; I2 = 59.4%; 3 studies) in 248 patients on hemodialysis; 12.9% (11.8-14.0; I2 = 79.7%; 2 studies) in 3750 patients with rheumatic heart disease; 36.9% (29.7-44.3; I2 = 79.7; 2 studies) in 79 patients with sickle cell disease; 62.7% (49.0-74.7; 1 study) in 51 patients with chronic obstructive pulmonary disease; 25.4% (16.3-37.3; 1 study) in 63 patients with systemic lupus erythematous; 68.7% (62.8-74.1; 1 study) in 259 patients with cardiac surgery; and 7.4% (4.6-11.9; 1 study) in 202 patients with systemic sclerosis. No study reported PH incidence. From one international study (n = 209), PH etiologies were: left heart disease (68.9%), pulmonary arterial hypertension (15.8%), lung disease and/or hypoxia (12.0%), chronic thromboembolic PH (1.9%) and unclear/multifactorial PH (15.8%). CONCLUSION: The prevalence of PH is relatively high in some populations in Africa, perhaps mainly driven by left heart diseases, highlighting the need for context-specific interventions.
  • Thumbnail Image
    Item
    Open Access
    Risk Factors for Acquired Rifamycin and Isoniazid resistance: A systematic review and meta-analysis
    (Public Library of Science, 2015) Rockwood, Neesha; Abdullahi, Leila H; Wilkinson, Robert J; Meintjes, Graeme
    BACKGROUND: Studies looking at acquired drug resistance (ADR) are diverse with respect to geographical distribution, HIV co-infection rates, retreatment status and programmatic factors such as regimens administered and directly observed therapy. Our objective was to examine and consolidate evidence from clinical studies of the multifactorial aetiology of acquired rifamycin and/or isoniazid resistance within the scope of a single systematic review. This is important to inform policy and identify key areas for further studies. METHODS: Case-control and cohort studies and randomised controlled trials that reported ADR as an outcome during antitubercular treatment regimens including a rifamycin and examined the association of at least 1 risk factor were included. Post hoc, we carried out random effects Mantel-Haenszel weighted meta-analyses of the impact of 2 key risk factors 1) HIV and 2) baseline drug resistance on the binary outcome of ADR. Heterogeneity was assessed used I 2 statistic. As a secondary outcome, we calculated median cumulative incidence of ADR, weighted by the sample size of the studies. RESULTS: Meta-analysis of 15 studies showed increased risk of ADR with baseline mono- or polyresistance (RR 4.85 95% CI 3.26 to 7.23, heterogeneity I 2 58%, 95% CI 26 to 76%). Meta-analysis of 8 studies showed that HIV co-infection was associated with increased risk of ADR (RR 3.02, 95% CI 1.28 to 7.11); there was considerable heterogeneity amongst these studies (I 2 81%, 95% CI 64 to 90%). Non-adherence, extrapulmonary/disseminated disease and advanced immunosuppression in HIV co-infection were other risk factors noted. The weighted median cumulative incidence of acquired multi drug resistance calculated in 24 studies (assuming whole cohort as denominator, regardless of follow up DST) was 0.1% (5 th to 95 th percentile 0.07 to 3.2%). CONCLUSION: Baseline drug resistance and HIV co-infection were significant risk factors for ADR. There was a trend of positive association with non-adherence which is likely to contribute to the outcome of ADR. The multifactorial aetiology of ADR in a programmatic setting should be further evaluated via appropriately designed studies.
  • Thumbnail Image
    Item
    Open Access
    Systematic review of TST responses in people living with HIV in under-resourced settings: implications for isoniazid preventive therapy
    (Public Library of Science, 2012) Kerkhoff, Andrew D; Kranzer, Katharina; Samandari, Taraz; Nakiyingi-Miiro, Jessica; Whalen, Christopher C; Harries, Anthony D; Lawn, Stephen D
    BACKGROUND: People living with HIV (PLWH) who have positive tuberculin skin tests (TST) benefit from isoniazid preventive therapy (IPT) whereas those testing TST-negative do not. Revised World Health Organization guidelines explicitly state that assessment of TST is not a requirement for initiation of IPT. However, it is not known what proportions of patients will benefit from IPT if implemented without targeting according to TST status. We therefore determined the proportions of PLWH who test TST-positive. METHODOLOGY/PRINCIPAL FINDINGS: We systematically reviewed the literature published between January 1990 and February 2012 to determine the proportions of patients without active tuberculosis attending HIV care services in low and middle-income countries who tested TST-positive (≥5 mm induration). Proportions were also determined for different CD4 count strata. Data from 19 studies with 9,478 PLWH from sub-Saharan Africa, Asia and Central and South America were summarized. The vast majority were not receiving antiretroviral therapy (ART). A sub-analysis was conducted of 5 studies (5,567 subjects) from high TB prevalence countries of PLWH with negative TB screens attending HIV care and treatment settings for whom CD4 stratified data were available. The median proportion of PLWH testing TST-positive overall was 22.8% (range, 19.5-32.6%). The median (range) proportions with CD4 cell counts of <200, 200-499 or ≥500 cells/µL who tested positive were 12.4% (8.2-15.3%), 28.4% (20.1-36.9%) and 37.4% (31.3-56.3%), respectively. Heterogeneity in the data precluded calculation of pooled summary estimates. Conclusions/Significance In most settings, if IPT is administered to PLWH pre-ART without assessment of TST status, only a minority of those treated are likely to benefit, especially among those with the lowest CD4 cell counts. This may be inefficient use of resources and cost-effectiveness analyses should take this into account. Local knowledge of TST response rates may help inform policies. New simple means of identifying those who will benefit from IPT are needed to permit appropriate targeting of this intervention.
  • Thumbnail Image
    Item
    Open Access
    Ventriculoperitoneal shunt insertion in human immunodeficiency virus infected adults: a systematic review and meta-analysis
    (2020-04-17) Loan, James J M; Poon, Michael T C; Tominey, Steven; Mankahla, Ncedile; Meintjes, Graeme; Fieggen, A. G
    Abstract Background Hydrocephalus is a common, life threatening complication of human immunodeficiency virus (HIV)-related central nervous system opportunistic infection which can be treated by insertion of a ventriculoperitoneal shunt (VPS). In HIV-infected patients there is concern that VPS might be associated with unacceptably high mortality. To identify prognostic indicators, we aimed to compare survival and clinical outcome following VPS placement between all studied causes of hydrocephalus in HIV infected patients. Methods The following electronic databases were searched: The Cochrane Central Register of Controlled Trials, MEDLINE (PubMed), EMBASE, CINAHL Plus, LILACS, Research Registry, the metaRegister of Controlled Trials, ClinicalTrials.gov, African Journals Online, and the OpenGrey database. We included observational studies of HIV-infected patients treated with VPS which reported of survival or clinical outcome. Data was extracted using standardised proformas. Risk of bias was assessed using validated domain-based tools. Results Seven Hunderd twenty-three unique study records were screened. Nine observational studies were included. Three included a total of 75 patients with tuberculous meningitis (TBM) and six included a total of 49 patients with cryptococcal meningitis (CM). All of the CM and two of the TBM studies were of weak quality. One of the TBM studies was of moderate quality. One-month mortality ranged from 62.5–100% for CM and 33.3–61.9% for TBM. These pooled data were of low to very-low quality and was inadequate to support meta-analysis between aetiologies. Pooling of results from two studies with a total of 77 participants indicated that HIV-infected patients with TBM had higher risk of one-month mortality compared with HIV non-infected controls (odds ratio 3.03; 95% confidence-interval 1.13–8.12; p = 0.03). Conclusions The evidence base is currently inadequate to inform prognostication in VPS insertion in HIV-infected patients. A population-based prospective cohort study is required to address this, in the first instance.