50 research outputs found
Increasing the use of second-line therapy is a cost-effective approach to prevent the spread of drug-resistant HIV: a mathematical modelling study
METHODS: We develop a deterministic mathematical model representing Kampala, Uganda, to predict the prevalence of TDR over a 10-year period. We then compare the impact on TDR and cost-effectiveness of: (1) introduction of pre-therapy genotyping; (2) doubling use of second-line treatment to 80% (50-90%) of patients with confirmed virological failure on first-line ART; and (3) increasing viral load monitoring from yearly to twice yearly. An intervention can be considered cost-effective if it costs less than three times the gross domestic product per capita per quality adjusted life year (QALY) gained, or less than 1612 to 450-dominated) per QALY gained.CONCLUSIONS: While earlier treatment initiation will result in a predicted increase in the proportion of patients infected with drug-resistant HIV, the absolute numbers of patients infected with drug-resistant HIV is predicted to decrease. Increasing use of second-line treatment to all patients with confirmed failure on first-line therapy is a cost-effective approach to reduce TDR. Improving access to second-line ART is therefore a major priority.INTRODUCTION: Earlier antiretroviral therapy (ART) initiation reduces HIV-1 incidence. This benefit may be offset by increased transmitted drug resistance (TDR), which could limit future HIV treatment options. We analyze the epidemiological impact and cost-effectiveness of strategies to reduce TDR
Spectrum: a model platform for linking maternal and child survival interventions with AIDS, family planning and demographic projections
Background LiST is implemented in Spectrum, a modular computer program designed to examine the impact of interventions on health outcomes. A typical LiST application uses three other modules in Spectrum addressing demography, family planning and HIV/AIDS
Creating and Validating an Algorithm to Measure AIDS Mortality in the Adult Population using Verbal Autopsy
BACKGROUND: Vital registration and cause of death reporting is incomplete in the countries in which the HIV epidemic is most severe. A reliable tool that is independent of HIV status is needed for measuring the frequency of AIDS deaths and ultimately the impact of antiretroviral therapy on mortality. METHODS AND FINDINGS: A verbal autopsy questionnaire was administered to caregivers of 381 adults of known HIV status who died between 1998 and 2003 in Manicaland, eastern Zimbabwe. Individuals who were HIV positive and did not die in an accident or during childbirth (74%; n = 282) were considered to have died of AIDS in the gold standard. Verbal autopsies were randomly allocated to a training dataset (n = 279) to generate classification criteria or a test dataset (n = 102) to verify criteria. A rule-based algorithm created to minimise false positives had a specificity of 66% and a sensitivity of 76%. Eight predictors (weight loss, wasting, jaundice, herpes zoster, presence of abscesses or sores, oral candidiasis, acute respiratory tract infections, and vaginal tumours) were included in the algorithm. In the test dataset of verbal autopsies, 69% of deaths were correctly classified as AIDS/non-AIDS, and it was not necessary to invoke a differential diagnosis of tuberculosis. Presence of any one of these criteria gave a post-test probability of AIDS death of 0.84. CONCLUSIONS: Analysis of verbal autopsy data in this rural Zimbabwean population revealed a distinct pattern of signs and symptoms associated with AIDS mortality. Using these signs and symptoms, demographic surveillance data on AIDS deaths may allow for the estimation of AIDS mortality and even HIV prevalence
Building blocks for meta-synthesis: data integration tables for summarising, mapping, and synthesising evidence on interventions for communicating with health consumers
<p>Abstract</p> <p>Background</p> <p>Systematic reviews have developed into a powerful method for summarising and synthesising evidence. The rise in systematic reviews creates a methodological opportunity and associated challenges and this is seen in the development of overviews, or reviews of systematic reviews. One of these challenges is how to summarise evidence from systematic reviews of complex interventions for inclusion in an overview. Interventions for communicating with and involving consumers in their care are frequently complex. In this article we outline a method for preparing data integration tables to enable review-level synthesis of the evidence on interventions for communication and participation in health.</p> <p>Methods and Results</p> <p>Systematic reviews published by the Cochrane Consumers and Communication Review Group were utilised as the basis from which to develop linked steps for data extraction, evidence assessment and synthesis. The resulting output is called a data integration table. Four steps were undertaken in designing the data integration tables: first, relevant information for a comprehensive picture of the characteristics of the review was identified from each review, extracted and summarised. Second, results for the outcomes of the review were assessed and translated to standardised evidence statements. Third, outcomes and evidence statements were mapped into an outcome taxonomy that we developed, using language specific to the field of interventions for communication and participation. Fourth, the implications of the review were assessed after the mapping step clarified the level of evidence available for each intervention.</p> <p>Conclusion</p> <p>The data integration tables represent building blocks for constructing overviews of review-level evidence and for the conduct of meta-synthesis. Individually, each table aims to improve the consistency of reporting on the features and effects of interventions for communication and participation; provides a broad assessment of the strength of evidence derived from different methods of analysis; indicates a degree of certainty with results; and reports outcomes and gaps in the evidence in a consistent and coherent way. In addition, individual tables can serve as a valuable tool for accurate dissemination of large amounts of complex information on communication and participation to professionals as well as to members of the public.</p
Multicentre RCT and economic evaluation of a psychological intervention together with a leaflet to reduce risk behaviour amongst men who have sex with men (MSM) prescribed post-exposure prophylaxis for HIV following sexual exposure (PEPSE): A protocol
Background: Post-exposure prophylaxis (PEP) following sexual exposure to HIV has been recommended as a method of preventing HIV infection in the UK. Men who have sex with men (MSM) are the group most affected by HIV in the UK and their sexual risk taking behaviour is reported to be increasing. One-to-one behavioural interventions, such as motivational interviewing (MI) have been recommended to reduce HIV in high risk groups. The Information, Motivation and Behavioral skills (IMB) model has been shown to provide a good basis for understanding and predicting HIV-relevant health behaviour and health behaviour change, however the IMB has yet to be applied to PEP after risky sexual exposure. The primary aim of this trial is to examine the impact of MI augmented with information provision and behavioural skills building (informed by the IMB Model), over and above usual care, on risky sexual behaviour in MSM prescribed PEP after potential sexual exposure. A secondary aim of this research is to examine the impact of the intervention on adherence to PEP. This study will also provide estimates of the cost-effectiveness of the intervention.
Methods: A manualised parallel group randomised controlled trial with economic evaluation will be conducted. The primary outcome is the proportion of risky sexual practices. Secondary outcomes include: i) Levels of adherence to PEP treatment; ii) Number of subsequent courses of PEP; iii) Levels of motivation to avoid risky sexual behaviours; iv) Levels of HIV risk-reduction information/knowledge; v) Levels of risk reduction behavioural skills; vi) Diagnosis of anal gonorrhoea, Chlamydia and/or HIV. 250 participants will be asked to self-complete a questionnaire at four time points during the study (at 0,3,6,12 months). The intervention will consist of a two-session, fixed duration, telephone administered augmented MI intervention based on the IMB model. A newly developed treatment manual will guide the selection of persuasive communication strategies as appropriate for each participant and will be based on underlying change mechanisms specified by the IMB theoretical framework. Information provision and skills building will also be included in the intervention package through the use of information leaflets and tailored action plans. Fidelity of intervention delivery will be assessed.
Discussion: The results from this NIHR funded study will identify whether it is appropriate and cost-effective to intervene using one-to-one telephone calls with MSM seeking PEP. If the intervention is effective, further work will be needed on training staff to deliver the intervention competently
Perinatal HIV transmission and the cost-effectiveness of screening at 14 weeks gestation, at the onset of labour and the rapid testing of infants
<p>Abstract</p> <p>Background</p> <p>Preventing HIV transmission is a worldwide public health issue. Vertical transmission of HIV from a mother can be prevented with diagnosis and treatment, but screening incurs cost. The U.S. Virgin Islands follows the mainland policy on antenatal screening for HIV even though HIV prevalence is higher and rates of antenatal care are lower. This leads to many cases of vertically transmitted HIV. A better policy is required for the U.S. Virgin Islands.</p> <p>Methods</p> <p>The objective of this research was to estimate the cost-effectiveness of relevant HIV screening strategies for the antenatal population in the U.S. Virgin Islands. An economic model was used to evaluate the incremental costs and incremental health benefits of nine different combinations of perinatal HIV screening strategies as compared to existing practice from a societal perspective. Three opportunities for screening were considered in isolation and in combination: by 14 weeks gestation, at the onset of labor, or of the infant after birth. The main outcome measure was the cost per life year gained (LYG).</p> <p>Results</p> <p>Results indicate that all strategies would produce benefits and save costs. Universal screening by 14 weeks gestation and screening the infant after birth is the recommended strategy, with cost savings of $1,122,787 and health benefits of 310 LYG. Limitations include the limited research on the variations in screening acceptance of screening based on specimen sample, race and economic status. The benefits of screening after 14 weeks gestation but before the onset of labor were also not addressed.</p> <p>Conclusion</p> <p>This study highlights the benefits of offering screening at different opportunities and repeat screening and raises the question of generalizing these results to other countries with similar characteristics.</p
Performance of self-reported HIV status in determining true HIV status among older adults in rural South Africa: a validation study
Abstract Introduction:: In South Africa, older adults make up a growing proportion of people living with HIV. HIV programmes are likely to reach older South Africans in home-based interventions where testing is not always feasible. We evaluate the accuracy of self-reported HIV status, which may provide useful information for targeting interventions or offer an alternative to biomarker testing. Methods:: Data were taken from the Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI) baseline survey, which was conducted in rural Mpumalanga province, South Africa. A total of 5059 participants aged ≥40 years were interviewed from 2014 to 2015. Self-reported HIV status and dried bloodspots for HIV biomarker testing were obtained during at-home interviews. We calculated sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for self-reported status compared to “gold standard” biomarker results. Log-binomial regression explored associations between demographic characteristics, antiretroviral therapy (ART) status and sensitivity of self-report. Results:: Most participants (93%) consented to biomarker testing. Of those with biomarker results, 50.9% reported knowing their HIV status and accurately reported it. PPV of self-report was 94.1% (95% confidence interval (CI): 92.0–96.0), NPV was 87.2% (95% CI: 86.2–88.2), sensitivity was 51.2% (95% CI: 48.2–54.3) and specificity was 99.0% (95% CI: 98.7–99.4). Participants on ART were more likely to report their HIV-positive status, and participants reporting false-negatives were more likely to have older HIV tests. Conclusions:: The majority of participants were willing to share their HIV status. False-negative reports were largely explained by lack of testing, suggesting HIV stigma is retreating in this setting, and that expansion of HIV testing and retesting is still needed in this population. In HIV interventions where testing is not possible, self-reported status should be considered as a routine first step to establish HIV status
Factors associated with HIV infection among children born to mothers on the prevention of mother to child transmission programme at Chitungwiza Hospital, Zimbabwe, 2008
Gender difference in HIV-1 RNA viral loads.
OBJECTIVES: To test and characterize the dependence of viral load on gender in different countries and racial groups as a function of CD4 T-cell count. METHODS: Plasma viral load data were analysed for > 30,000 HIV-infected patients attending clinics in the USA [HIV Insight (Cerner Corporation, Vienna, VA, USA) and Plum Data Mining LLC (East Meadow, NY, USA) databases] and the Netherlands (Athena database; HIV Monitoring Foundation, Amsterdam, Netherlands). Log-normal regression models were used to test for an effect of gender on viral load while adjusting for covariates and allowing the effect to depend on CD4 T-cell count. Sensitivity analyses were performed to test the robustness of conclusions to assumptions regarding viral loads below the lower limit of quantification (LLOQ). RESULTS: After adjusting for covariates, women had (nonsignificantly) lower viral loads than men (HIV Insight: -0.053 log(10) HIV-1 RNA copies/mL, P = 0.202; Athena: -0.005 log(10) copies/mL, P = 0.667; Plum: -0.072 log(10) copies/mL, P = 0.273). However, further investigation revealed that the gender effect depended on CD4 T-cell count. Women had consistently higher viral loads than men when CD4 T-cell counts were at most 50 cells/microL, and consistently lower viral loads than men when CD4 T-cell counts were greater than 350 cells/microL. These effects were remarkably consistent when estimated independently for the racial groups with sufficient data available in the HIV Insight and Plum databases. CONCLUSIONS: The consistent relationship between gender-related differences in viral load and CD4 T-cell count demonstrated here explains the diverse findings previously published
