The Cochrane Library and mother-to-child transmission of HIV: an umbrella review

Review of social networks of professionals in healthcare settings-where are we and what else is needed?

Background

Social Network Analysis (SNA) demonstrates great potential in exploring health professional relationships and improving care delivery, but there is no comprehensive overview of its utilization in healthcare settings. This review aims to provide an overview of the current state of knowledge regarding the use of SNA in understanding health professional relationships in different countries.

Methods

We conducted an umbrella review by searching eight academic databases and grey literature up to April 30, 2021, enhanced by citation searches. We completed study selection, data extraction and quality assessment using predetermined criteria. The information abstracted from the reviews was synthesized quantitatively, qualitatively and narratively.

Results

Thirteen reviews were included in this review, yielding 330 empirical studies. The degree of overlaps of empirical studies across included reviews was low (4.3 %), indicating a high diversity of included reviews and the necessity of this umbrella review. Evidence from low- and middle-income countries (LMIC), particularly Asian countries, was limited. The earliest review was published in 2010 and the latest in 2019. Six reviews focused on the construction or description of professional networks and seven reviews reported factors or influences of professional networks. We synthesized existing literature on social networks of health care professionals in the light of (i) theoretical frameworks, (ii) study design and data collection, (iii) network nodes, measures and analysis, and (iv) factors of professional networks and related outcomes. From the perspective of methodology, evidence lies mainly in cross-sectional study design and electronic data, especially administrative data showing “patient-sharing” relationships, which has become the dominant data collection method. The results about the impact of health professional networks on health-related consequences were often contradicting and not truly comparable.

Conclusions

Methodological limitations, inconsistent findings, and lack of evidence from LMIC imply an urgent need for further investigations. The potential for broader utilization of SNA among providers remains largely untapped and the findings of this review may contain important value for building optimal healthcare delivery networks.

PROSPERO registration number

The protocol was published and registered with PROSPERO, the International Prospective Register of Systematic Reviews (CRD42020205996).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12992-021-00772-7.

Interventions for preventing mother-to-child HIV transmission: protocol of an overview of systematic reviews

INTRODUCTION

Various interventions to prevent mother-to-child-transmission (MTCT) of HIV have been investigated and implemented. A number of systematic reviews assessing the efficacy of interventions for the prevention of MTCT of HIV reported antiretroviral prophylaxis, caesarean section before labour and before ruptured membranes, and complete avoidance of breastfeeding were efficacious for preventing MTCT of HIV. Recent WHO guidelines recommend lifelong antiretroviral therapy for all pregnant women for treatment of the woman's own HIV infection and for prevention of MTCT of HIV. Therefore, the objective of this overview is to evaluate the currently available systematic reviews of interventions for preventing MTCT of HIV, and to identify the current best evidence-based interventions for reducing the risk of MTCT of HIV.

METHODS AND ANALYSIS

We will include only peer-reviewed systematic reviews of randomised or quasi-randomised controlled trials assessing the effects of interventions for preventing MTCT of HIV that target both HIV-infected women and children aged 2 years and younger born to HIV-infected women. We will search the Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effectiveness, Ovid MEDLINE and EMBASE. We will assess review eligibility, the methodological quality of included systematic reviews using A Measurement Tool to Assess The Systematic Reviews and will extract data, comparing our results and resolving discrepancies by consensus. Finally, we will independently assess the certainty of the evidence using Grades of Recommendation, Assessment, Development and Evaluation.

ETHICS AND DISSEMINATION

Ethics approval is not required. We will publish the results in a peer-reviewed journal and present at conferences, which will inform future research and will be useful for healthcare managers, administrators and policymakers to guide resource allocation decisions and optimisation of interventions to prevent the MTCT of HIV.

Improvement in antenatal testing for sexually transmissible infections and blood-borne viruses in Western Australian hospitals, 2007 to 2010

Objective Antenatal testing for specified sexually transmissible infections (STIs) and blood-borne viruses (BBVs) is recommended by the Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG). In 2007, the Department of Health, Western Australia (DoHWA) issued an operational directive (OD) recommending universal testing for chlamydia and additional testing for women in the STI endemic regions of Western Australia (WA). To assess adherence to these guidelines, seven WA public hospitals were audited. Design and setting: Demographic details and testing information of the last 200 women who gave birth immediately before 30 June 2007 (baseline audit) and 30 June 2010 (follow-up audit) were obtained from each hospital’s antenatal records. Results: Data from 2718 women who delivered at ≥36 weeks’ gestation were analysed (baselinen = 1353; follow-upn = 1365). Testing at the first antenatal visit in accordance with the guidelines improved over time (RANZCOG: 68–74%; χ2-test = 13.96, d.f. = 1, P < 0.001; DoHWA OD: 12–40%; χ2-test = 279.71, d.f. = 1, P < 0.001). Retesting at 28–36 weeks’ gestation in the STI endemic regions improved for chlamydia (3–10%; χ2-test = 17.40, d.f. = 1, P < 0.001) and gonorrhoea (3–7%; χ2-test = 6.62, d.f. = 1, P < 0.05), but not for syphilis or HIV. Chlamydia prevalence was 3% and 8% among nonAboriginal and Aboriginal women, respectively. Conclusion: The proportion of women delivering in WA public hospitals who had antenatal STI and BBV tests improved after publication and promotion of the OD.

Antiretroviral therapy (ART) for treating HIV infection in ART-eligible pregnant women

BACKGROUND

This systematic review focuses on antiretroviral therapy (ART) for treating human immunodeficiency virus (HIV) infection in ART-eligible pregnant women. Mother-to-child transmission (MTCT) is the primary means by which children worldwide acquire HIV infection. MTCT occurs during three major timepoints during pregnancy and the postpartum period: in utero, intrapartum, and during breastfeeding. Strategies to reduce MTCT focus on these periods of exposure and include maternal and infant use of ART, caesarean section before onset of labour or rupture of membranes, and complete avoidance of breastfeeding. Where these combined interventions are available, the risk of MTCT is as low as 1-2%. Thus, ART used among mothers who require treatment of HIV for their own health also plays a significant role in decreasing MTCT.This review is one in a series of systematic reviews performed in preparation for the revision of the 2006 World Health Organization (WHO) Guidelines regarding "Antiretroviral Drugs for Treating Pregnant Women and Preventing HIV Infection in Infants" and "Antiretroviral therapy (ART) for HIV Infections in Adults and Adolescents." The findings from these reviews were discussed with experts, key stakeholders, and country representatives at the 2009 WHO guideline review meeting. The resulting WHO 2009 "rapid advice" preliminary guidance on adult and adolescent ART now recommends lifelong treatment for all adults with HIV infection and CD4 counts <350 cells/mm(3). These recommendations also apply to pregnant women who are HIV-infected and they place a high value on early ART to benefit the mother's own health (WHO 2009). The "rapid advice" preliminary guidance also aims to minimize side effects for mothers and their infants (WHO 2009).

OBJECTIVES

Our objective was to assess the current literature regarding the treatment of HIV infection in pregnant women who are clinically or immunologically eligible for ART. This review includes an evaluation of the optimal time to start therapy in relation to the woman's laboratory parameters and/or gestational age. It also includes an analysis of which specific antiretroviral medications to start in women who are not yet on ART and which agents to continue in women who are already on ART.

SEARCH STRATEGY

In June 2009, electronic searches were undertaken in these databases: Cochrane's "CENTRAL," EMBASE, PubMed, LILACS, and Web of Science/Web of Social Science. Hand searches were performed of the reference lists of all pertinent reviews and studies identified. Abstracts from relevant conferences were searched. Experts in the field were contacted to locate additional studies. The search strategy was iterative.

SELECTION CRITERIA

We selected randomized controlled trials and observational studies that evaluated pregnant women with HIV infection who were eligible for ART according to criteria defined by the WHO guideline review committee. Studies were included in the systematic review when a comparison group was clearly defined and where the intervention comprised triple ART. For a study to be considered, each medication in the ART regimen needed to be clearly described.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the selected studies for relevance and inclusion. Relevant data was then extracted from included studies, and the risk of bias assessed. In each included study, the relative risk (RR) for the intervention versus the comparison group was calculated for each outcome, as appropriate, with 95% confidence intervals (CIs).

MAIN RESULTS

To our knowledge, there are no randomized controlled trials or observational studies that address the optimal time to start antiretroviral drugs in ART-eligible pregnant women in relation to the woman's laboratory parameters and/or gestational age. The medications to continue in ART-eligible pregnant women who are already receiving ART also have not been evaluated systematically in the current literature. The long-term mortality of HIV-positive pregnant women on ART for their own health, and the long-term virologic or clinical efficacy of ART in treating them, has not been evaluated in randomized clinical trials. In this review, surrogate outcomes for long-term mortality and virologic and clinical efficacy (e.g. MTCT and infant HIV transmission or death) were evaluated to determine the efficacy of specific antiretroviral regimens to start in women who are not yet on ART.Three randomized controlled trials and six observational studies were selected. No studies addressed comparative maternal mortality, which regimens to continue in women already on ART, or the laboratory parameters and gestational age at which to start therapy. The use of zidovudine (AZT), lamivudine (3TC) and lopinavir/ritonavir (LPV-r) starting at 28-36 weeks gestation in a breastfeeding population reduced infant HIV-transmission or death at 12 months compared to a short-course regimen (RR 0.64, 95% CI: 0.44-0.92) (deVincenzi, 2009). Starting AZT, 3TC, and nevirapine (NVP) at 34 weeks in a mixed-feeding population reduced infant HIV-transmission or death at 7 months compared to a short-course regimen (RR 0.39, 95% CI: 0.12-0.85) (Bae, 2008).In the Mma Bana study (a randomized controlled trial in a breastfeeding population) there was no difference in MTCT at six months between the AZT/3TC/LPV-r and AZT, 3TC, and abacavir (ABC) arms (RR 0.17, 95% CI: 0.02-1.44) (Shapiro, 2009). Both regimens also showed 92-95% efficacy in virologic suppression at delivery and during the breastfeeding period. In the Kesho Bora study there was a significant difference in MTCT at 12 months between breastfeeding women who initiated AZT/3TC/LPV-r starting between 28 and 36 weeks and those receiving a short course regimen (RR 0.58, 95% CI: 0.34-0.97) (deVincenzi, 2009). MTCT also decreased significantly when AZT/3TC/NVP was compared with a short-course regimen at seven months in a feeding intervention study (RR 0.15, 95% CI: 0.04-0.62) (Bae, 2008) and 12 months in a population where either exclusive breastfeeding or replacement feeding was encouraged (RR 0.14, CI: 0.04-0.47) (Ekouevi, 2008).In the Mma Bana study, there was increased risk of prematurity among infants born to women receiving AZT/3TC/LPV-r (RR 1.52, CI: 1.07- 2.17) compared with AZT/3TC/ABC (Shapiro, 2009). Ekouevi 2008 showed higher rates of infant low birth weight on AZT/3TC/NVP started at 24 weeks compared to a short course regimen started between 32 and 36 weeks (RR 1.81, 95% CI: 1.09- 3.0). Tonwe-Gold 2007 showed an increase in maternal severe adverse events among the women receiving AZT/3TC/NVP compared with a short-course regimen (RR 25.33, CI 1.49- 340.51).

AUTHORS' CONCLUSIONS

In ART-eligible pregnant women with HIV infection, ART is a safe and effective means of providing maternal virologic suppression, decreasing infant mortality, and reducing MTCT. Specifically, AZT/3TC/NVP, AZT/3TC/LPV-r, and AZT/3TC/ABC have been shown to decrease MTCT. More research is needed regarding the use of specific regimens and their maternal and infant side-effect profiles.

A typology of reviews: an analysis of 14 review types and associated methodologies

BACKGROUND AND OBJECTIVES

The expansion of evidence-based practice across sectors has lead to an increasing variety of review types. However, the diversity of terminology used means that the full potential of these review types may be lost amongst a confusion of indistinct and misapplied terms. The objective of this study is to provide descriptive insight into the most common types of reviews, with illustrative examples from health and health information domains.

METHODS

Following scoping searches, an examination was made of the vocabulary associated with the literature of review and synthesis (literary warrant). A simple analytical framework -- Search, AppraisaL, Synthesis and Analysis (SALSA) -- was used to examine the main review types.

RESULTS

Fourteen review types and associated methodologies were analysed against the SALSA framework, illustrating the inputs and processes of each review type. A description of the key characteristics is given, together with perceived strengths and weaknesses. A limited number of review types are currently utilized within the health information domain.

CONCLUSIONS

Few review types possess prescribed and explicit methodologies and many fall short of being mutually exclusive. Notwithstanding such limitations, this typology provides a valuable reference point for those commissioning, conducting, supporting or interpreting reviews, both within health information and the wider health care domain.

Interventions for preventing late postnatal mother-to-child transmission of HIV

BACKGROUND

Worldwide, mother-to-child transmission (MTCT) of human immunodeficiency virus type 1 (HIV) represents the most common means by which children acquire HIV infection. Efficacious and effective interventions to prevent in utero and intrapartum transmission of HIV infection have been developed and implemented. However, a large proportion of MTCT of HIV occurs postnatally, through breast milk transmission.

OBJECTIVES

The objectives of this systematic review were to collate and assess the evidence regarding interventions to decrease late postnatal MTCT of HIV, and to determine the efficacy of such interventions in decreasing late postnatal MTCT of HIV, increasing overall survival, and increasing HIV-free survival.

SEARCH STRATEGY

Electronic searches were undertaken using PubMed, EMBASE and other databases for 1980-2008. Hand searches of reference lists of pertinent reviews and studies, as well as abstracts from relevant conferences, were also conducted. Experts in the field were contacted to locate any other studies. The search strategy was iterative.

SELECTION CRITERIA

Randomized clinical trials assessing the efficacy of interventions to prevent MTCT of HIV through breast milk were included in the analysis. Other trials and intervention cohort studies with relevant data also were included, but only when randomization was not feasible due to the nature of the intervention (i.e., infant feeding modality).

DATA COLLECTION AND ANALYSIS

Data regarding HIV infection status and vital status of infants born to HIV-infected women, according to intervention, were extracted from the reports of the studies.

MAIN RESULTS

Six randomized clinical trials and one intervention cohort study were included in this review. Two trials addressed the issue of shortening the duration of (or eliminating) exposure to breast milk. In a trial of breastfeeding versus formula feeding, formula feeding was efficacious in preventing MTCT of HIV (the cumulative probability of HIV infection at 24 months was 36.7% in the breastfeeding arm and 20.5% in the formula arm [p = 0.001]), but the mortality and malnutrition rates during the first two years of life were similar in the two groups. In a trial of early cessation of breastfeeding, HIV-free survival was similar between those children who ceased breastfeeding around four months of age and those who continued breastfeeding. Another trial addressing vitamin supplementation found more cases of HIV infection among children of mothers in the vitamin A arm. Efficacy for other vitamin supplements was not shown. An intervention cohort study evaluated the risk of MTCT according to infant feeding modality, and found increased risks of MTCT among breastfed children who also received solids (hazard ratio = 10.87, p = 0.018) as well as higher 3-month mortality rates (hazard ratio = 2.06) among infants given non- breast milk feedings (instead of exclusive breastfeeding). Three trials evaluated antiretroviral prophylaxis to breastfeeding infants. One trial found that breastfeeding with zidovudine prophylaxis (transmission rate = 9.0%) was not as effective as formula feeding (transmission rate 5.6%) in preventing late postnatal HIV transmission (p = 0.04). Breastfeeding with zidovudine prophylaxis and formula feeding had comparable HIV-free survival rates at 18 months (p = 0.60). Two trials of extended nevirapine prophylaxis demonstrated efficacy. In the first (data combined from trials conducted in three different countries), a six-week course of nevirapine resulted in a lower risk of HIV transmission by six weeks of age (p=0.009), but not at six months of age (p = 0.016). In the second, nevirapine administration until 14 weeks of age (5.2%) or nevirapine with zidovudine until 14 weeks of age (6.4%) resulted in significantly lower risks of MTCT of HIV by 9 months of age than a control regimen of peripartum prophylaxis (10.6%) (p < 0.001). HIV-free survival was significantly better through the age of 9 months in both extended prophylaxis groups, and through the age of 15 months in the extended nevirapine group.

AUTHORS' CONCLUSIONS

Complete avoidance of breastfeeding is efficacious in preventing MTCT of HIV, but this intervention has significant associated morbidity (e.g., diarrheal morbidity if formula is prepared without clean water). If breastfeeding is initiated, two interventions 1). exclusive breastfeeding during the first few months of life; and 2) chronic antiretroviral prophylaxis to the infant (nevirapine alone, or nevirapine with zidovudine) are efficacious in preventing transmission.