HIV transmission risk through anal intercourse: systematic review, meta-analysis and implications for HIV prevention
01 Aug 2010-International Journal of Epidemiology (Oxford University Press)-Vol. 39, Iss: 4, pp 1048-1063
TL;DR: It was demonstrated that it would require unreasonably low numbers of AI HIV exposures per partnership to reconcile the summary per-act and per-partner estimates, suggesting considerable variability in AI infectiousness between and within partnerships over time.
Abstract: Background The human immunodeficiency virus (HIV) infectiousness of anal intercourse (AI) has not been systematically reviewed, despite its role driving HIV epidemics among men who have sex with men (MSM) and its potential contribution to heterosexual spread. We assessed the per-act and per-partner HIV transmission risk from AI exposure for heterosexuals and MSM and its implications for HIV prevention.
Methods Systematic review and meta-analysis of the literature on HIV-1 infectiousness through AI was conducted. PubMed was searched to September 2008. A binomial model explored the individual risk of HIV infection with and without highly active antiretroviral therapy (HAART).
Results A total of 62 643 titles were searched; four publications reporting per-act and 12 reporting per-partner transmission estimates were included. Overall, random effects model summary estimates were 1.4% [95% confidence interval (CI) 0.2–2.5)] and 40.4% (95% CI 6.0–74.9) for per-act and per-partner unprotected receptive AI (URAI), respectively. There was no significant difference between per-act risks of URAI for heterosexuals and MSM. Per-partner unprotected insertive AI (UIAI) and combined URAI–UIAI risk were 21.7% (95% CI 0.2–43.3) and 39.9% (95% CI 22.5–57.4), respectively, with no available per-act estimates. Per-partner combined URAI–UIAI summary estimates, which adjusted for additional exposures other than AI with a ‘main’ partner [7.9% (95% CI 1.2–14.5)], were lower than crude (unadjusted) estimates [48.1% (95% CI 35.3–60.8)]. Our modelling demonstrated that it would require unreasonably low numbers of AI HIV exposures per partnership to reconcile the summary per-act and per-partner estimates, suggesting considerable variability in AI infectiousness between and within partnerships over time. AI may substantially increase HIV transmission risk even if the infected partner is receiving HAART; however, predictions are highly sensitive to infectiousness assumptions based on viral load.
Conclusions Unprotected AI is a high-risk practice for HIV transmission, probably with substantial variation in infectiousness. The significant heterogeneity between infectiousness estimates means that pooled AI HIV transmission probabilities should be used with caution. Recent reported rises in AI among heterosexuals suggest a greater understanding of the role AI plays in heterosexual sex lives may be increasingly important for HIV prevention.
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TL;DR: It is indicated that HAI may be an important driver of the HIV epidemic in PNG and efforts are required to improve behavioural surveillance of HAI as well as develop national HIV/STI programing and policy to better address the risks associated with unprotected HAI.
Abstract: Background
Papua New Guinea (PNG) has a high burden of sexually transmitted infections (STIs) and the highest adult HIV prevalence in the Pacific region. Despite this burden of disease, heterosexual anal intercourse (HAI) has rarely been considered. Given the increasing number of, and interest in, behavioural surveys in PNG and the changing nature of PNG’s HIV epidemic, it is timely to conduct a systematic review of HAI in PNG order to improve sexual health.
10 citations
Cites background from "HIV transmission risk through anal ..."
...While some caution is required for pooled transmission probabilities, it is clear that unprotected HAI poses greater risk for females than does vaginal intercourse [7]....
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...Background Irrespective of whether penile-anal intercourse is occurring between a male and a female or two males, penileanal intercourse is associated with greater risk of HIV transmission than penile-vaginal intercourse [1-7]....
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...This is important because HAI may play a larger role in HIV transmission in the general population than previously thought [7]....
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Dissertation•
01 Oct 2017
TL;DR: The central argument of this thesis is that highly valued legal, societal and religious guiding precepts of Nigerian society coupled with the double stigmatizing identities of being both HIV positive and MSM are propagating the everyday stigma, discrimination and extreme violence, which they experience.
Abstract: Despite the large body of evidence suggesting that African MSM have poor healthcare seeking behavior, there remains a paucity of research especially qualitative research exploring healthcare seeking practices among Nigerian MSM. This thesis provided a nuanced exploration of the ‘lived’ experiences of HIV positive MSM as they seek to access healthcare services including adhering to antiretroviral treatment (ART) in Nigeria. The central argument of this thesis is that highly valued legal, societal and religious guiding precepts of Nigerian society coupled with the double stigmatizing identities of being both HIV positive and MSM are propagating the everyday stigma, discrimination and extreme violence, which they experience. These stigma, discrimination and violence further act to negatively influence the healthcare seeking practices of HIV positive MSM, especially the extent in which they are able to gain access to healthcare services and adhere to ART. In exploring the lived experience of HIV positive MSM, a qualitative approach using Focus Group Discussions (FGDs) and an Semi-Structured Interview were employed. A total of 4 FGDs and 21 interviews were conducted in both Lagos and Abuja, Nigeria, between January and May 2016. Data were analysed iteratively using both thematic and individual analysis in order to obtain a comprehensive picture of the men’s lived experiences. Findings reveal that HIV positive MSM access sexual and HIV related healthcare services from facilities which are specifically targeted at their population. This is due to the experience of stigma and discrimination as well as the fear of persecution at general healthcare facilities. When they do seek healthcare services from general healthcare services, in a bid to conceal their sexual orientation and avoid stigma or persecution, they falsify symptoms and this leads to misdiagnosis and in some cases death. This thesis reported on a form of stigma ‘Kito’, which is driven by the criminalisation of homosexuality, poverty, social media, religion and norms of the society. This thesis also revealed that HIV positive MSM living in Nigeria lacked knowledge about the transmission of HIV through anal sex and therefore engaged in anal sex as a protective behavior leading to their acquisition of HIV infection. MSM encounter challenges to adhering to ART which fall under patient, ART and social or structural related challenges. The study also highlighted that HIV positive MSM in Nigeria adopt strategies such as setting alarms, repackaging and breaking their ART in smaller easier to swallow pieces, selectively disclose their HIV status and conceal their ART in order to maintain optimal adherence to ART. Findings from this research can inform public health interventions geared at improving engagement with healthcare services including access and adherence to ART among this key population. Additionally, it raises the question of what an effective health education strategy for non-heterosexual men should look like in a context which is highly heteronormative and where same-sex practices and identities are criminalised.
10 citations
Journal Article•
TL;DR: Social marketing should target the modifiable predictors of condom use, such as attitudes to safe sex, with interventions also need to engage successfully with GBM reporting non-modifiable traits such as HIV-positive GBM.
Abstract: AIMS To identify predictors of non-condom use among gay and bisexual men (GBM) in New Zealand with casual male partners. METHODS We analysed anonymous self-completed data from GBM who participated in the communitybased Gay Auckland Periodic Sex Survey (GAPSS) and Internet-based Gay Online Sex Survey (GOSS), undertaken in 2014. Infrequent condom use was defined as not using condoms "always" or "almost always" during anal intercourse in the prior six months. RESULTS Of the 1,912 GBM reporting anal intercourse with a casual partner, 27.2% reported infrequent condom use. Being recruited from Internet dating sites, Pacific ethnicity, having over 20 recent male partners, infrequent condom use with a current regular partner, or being HIV-positive were independently predictive of infrequent condom use. Conversely, being older, having a tertiary degree, using a condom at first anal intercourse, being exclusively receptive with a casual partner/s, and seeing condoms promoted through multiple channels predicted frequent condom use. Attitudes to condoms and safe sex were strongly predictive of actual condom use. CONCLUSIONS Social marketing should target the modifiable predictors of condom use, such as attitudes to safe sex. Interventions also need to engage successfully with GBM reporting non-modifiable traits such as HIV-positive GBM.
10 citations
Cites background from "HIV transmission risk through anal ..."
...1993;328(19):1365–1371 Competing interests: Mr Hingston is an experienced colonoscopist who derives income from performing colonoscopy....
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TL;DR: Qualitative data confirm health workers’ motivation to discuss anal sexuality and the value of learning about anal physiology and sexual response, but revealed continued uncertainty about how to broach and navigate discussion with clients.
Abstract: Health workers report challenges to broaching sexual behavior with gay and bisexual men (MSM). We conducted a stigma-mitigation training to increase provider-initiated conversation about anal sexuality among Chinese health workers. The two-day workshop, titled Smarter Sex is the New Safer Sex: Anal Pleasure and Health, coupled information about anal physiology and sexual response with gradual exposure to trainees' emotional and cognitive responses. We analyzed surveys and one-time interviews. Acceptability (satisfaction with training activities and recommended practices), feasibility (compatibility with participants' current practices), and appropriateness (perceived fit with participants' work mission and goals) were high, reaching 84-95% of the scale range, though with variable ratings for trainee comfort during participation. Qualitative data confirm health workers' motivation to discuss anal sexuality and the value of learning about anal physiology and sexual response, but revealed continued uncertainty about how to broach and navigate discussion with clients. Refinement of the training to align with health worker recommendations and to augment communication options and skills is warranted, as is involvement of MSM clientele themselves.
10 citations
TL;DR: The results indicate condom breakage is an important problem for MSM that may be more common for younger men, for men with more partners, and during sex with casual partners after alcohol consumption or drug use.
Abstract: Background: Within the United States, HIV affects men who have sex with men (MSM) disproportionally compared to the general population. In 2011, MSM represented nearly two-thirds of all new HIV infections while representing less than 2% of the US male population. Condoms continue to be the foundation of many HIV prevention programs; however, the failure rate of condoms during anal intercourse among MSM is estimated to be 0.5% to 8%, and condom breakages leave those affected at high risk for HIV transmission. Objective: Estimate the frequency of condom breakage and associated demographic and behavioral factors during last act of anal intercourse using data from a national online HIV prevention survey of MSM. Methods: From March 19 to April 16, 2009, data were collected on 9005 MSM through an online survey of US MSM recruited through a social networking site. Using multivariable logistic regression and controlling for several demographic and sexual risk behaviors, we estimated odds ratios of the association between condom breakage and several risk factors. Results: In the study, 8063 participants reported having at least one male sexual partner in the last 12 months. The median age of participants was 21 years (range 18-65). More than two-thirds (68.2%, 5498/8063) reported anal intercourse during last sex and 16.90% (927/5498) reported using a condom during last anal intercourse act. Condom breakage was reported by 4.4% (28/635) participants who engaged in receptive anal intercourse and 3.5% (16/459) participants who engaged in insertive anal intercourse, with an overall failure rate of 4.0% (95% CI 3.2%-6.0%). Age (adjusted odds ratio [aOR] per 5 years: 0.53 (95% CI 0.30-0.94), number of male sex partners (aOR per 5 sex partners: 1.03 (95% CI 1.00-1.08), and being high or buzzed during sex with a casual sex partner (aOR: 3.14, 95% CI 1.02-9.60) were associated with condom breakage. Conclusions: Our results indicate condom breakage is an important problem for MSM that may be more common for younger men, for men with more partners, and during sex with casual partners after alcohol consumption or drug use. A better understanding of why condom breakage occurs more often in these groups is needed to improve educational efforts. Further, during this time of expanded interest in new condom designs, consideration should be given to how condom design might minimize breakage during anal sex. [JMIR Public Health Surveill 2016;2(1):e7]
10 citations
Cites background from "HIV transmission risk through anal ..."
...While condoms remain a strong component of prevention policy, our findings indicate condoms may not suffice as a sole means of reducing HIV transmission risk within the context of a high per-act transmission risk of anal sex [6]....
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...The high prevalence of condomless anal intercourse among MSM coupled with the fact that anal intercourse is associated with greater HIV transmission probabilities compared to vaginal intercourse provides some explanation of the large burden of disease experienced among MSM [4-9]....
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References
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TL;DR: A new quantity is developed, I 2, which the authors believe gives a better measure of the consistency between trials in a meta-analysis, which is susceptible to the number of trials included in the meta- analysis.
Abstract: Cochrane Reviews have recently started including the quantity I 2 to help readers assess the consistency of the results of studies in meta-analyses. What does this new quantity mean, and why is assessment of heterogeneity so important to clinical practice?
Systematic reviews and meta-analyses can provide convincing and reliable evidence relevant to many aspects of medicine and health care.1 Their value is especially clear when the results of the studies they include show clinically important effects of similar magnitude. However, the conclusions are less clear when the included studies have differing results. In an attempt to establish whether studies are consistent, reports of meta-analyses commonly present a statistical test of heterogeneity. The test seeks to determine whether there are genuine differences underlying the results of the studies (heterogeneity), or whether the variation in findings is compatible with chance alone (homogeneity). However, the test is susceptible to the number of trials included in the meta-analysis. We have developed a new quantity, I 2, which we believe gives a better measure of the consistency between trials in a meta-analysis.
Assessment of the consistency of effects across studies is an essential part of meta-analysis. Unless we know how consistent the results of studies are, we cannot determine the generalisability of the findings of the meta-analysis. Indeed, several hierarchical systems for grading evidence state that the results of studies must be consistent or homogeneous to obtain the highest grading.2–4
Tests for heterogeneity are commonly used to decide on methods for combining studies and for concluding consistency or inconsistency of findings.5 6 But what does the test achieve in practice, and how should the resulting P values be interpreted?
A test for heterogeneity examines the null hypothesis that all studies are evaluating the same effect. The usual test statistic …
45,105 citations
TL;DR: A checklist contains specifications for reporting of meta-analyses of observational studies in epidemiology, including background, search strategy, methods, results, discussion, and conclusion should improve the usefulness ofMeta-an analyses for authors, reviewers, editors, readers, and decision makers.
Abstract: ObjectiveBecause of the pressure for timely, informed decisions in public health
and clinical practice and the explosion of information in the scientific literature,
research results must be synthesized. Meta-analyses are increasingly used
to address this problem, and they often evaluate observational studies. A
workshop was held in Atlanta, Ga, in April 1997, to examine the reporting
of meta-analyses of observational studies and to make recommendations to aid
authors, reviewers, editors, and readers.ParticipantsTwenty-seven participants were selected by a steering committee, based
on expertise in clinical practice, trials, statistics, epidemiology, social
sciences, and biomedical editing. Deliberations of the workshop were open
to other interested scientists. Funding for this activity was provided by
the Centers for Disease Control and Prevention.EvidenceWe conducted a systematic review of the published literature on the
conduct and reporting of meta-analyses in observational studies using MEDLINE,
Educational Research Information Center (ERIC), PsycLIT, and the Current Index
to Statistics. We also examined reference lists of the 32 studies retrieved
and contacted experts in the field. Participants were assigned to small-group
discussions on the subjects of bias, searching and abstracting, heterogeneity,
study categorization, and statistical methods.Consensus ProcessFrom the material presented at the workshop, the authors developed a
checklist summarizing recommendations for reporting meta-analyses of observational
studies. The checklist and supporting evidence were circulated to all conference
attendees and additional experts. All suggestions for revisions were addressed.ConclusionsThe proposed checklist contains specifications for reporting of meta-analyses
of observational studies in epidemiology, including background, search strategy,
methods, results, discussion, and conclusion. Use of the checklist should
improve the usefulness of meta-analyses for authors, reviewers, editors, readers,
and decision makers. An evaluation plan is suggested and research areas are
explored.
17,663 citations
TL;DR: The problem of making a combined estimate has been discussed previously by Cochran and Yates and Cochran (1937) for agricultural experiments, and by Bliss (1952) for bioassays in different laboratories as discussed by the authors.
Abstract: When we are trying to make the best estimate of some quantity A that is available from the research conducted to date, the problem of combining results from different experiments is encountered. The problem is often troublesome, particularly if the individual estimates were made by different workers using different procedures. This paper discusses one of the simpler aspects of the problem, in which there is sufficient uniformity of experimental methods so that the ith experiment provides an estimate xi of u, and an estimate si of the standard error of xi . The experiments may be, for example, determinations of a physical or astronomical constant by different scientists, or bioassays carried out in different laboratories, or agricultural field experiments laid out in different parts of a region. The quantity xi may be a simple mean of the observations, as in a physical determination, or the difference between the means of two treatments, as in a comparative experiment, or a median lethal dose, or a regression coefficient. The problem of making a combined estimate has been discussed previously by Cochran (1937) and Yates and Cochran (1938) for agricultural experiments, and by Bliss (1952) for bioassays in different laboratories. The last two papers give recommendations for the practical worker. My purposes in treating the subject again are to discuss it in more general terms, to take account of some recent theoretical research, and, I hope, to bring the practical recommendations to the attention of some biologists who are not acquainted with the previous papers. The basic issue with which this paper deals is as follows. The simplest method of combining estimates made in a number of different experiments is to take the arithmetic mean of the estimates. If, however, the experiments vary in size, or appear to be of different precision, the investigator may wonder whether some kind of weighted meani would be more precise. This paper gives recommendations about the kinds of weighted mean that are appropriate, the situations in which they
4,335 citations
TL;DR: The viral load is the chief predictor of the risk of heterosexual transmission of HIV-1, and transmission is rare among persons with levels of less than 1500 copies of HIV -1 RNA per milliliter.
Abstract: Background and Methods We examined the influence of viral load in relation to other risk factors for the heterosexual transmission of human immunodeficiency virus type 1 (HIV-1). In a community-based study of 15,127 persons in a rural district of Uganda, we identified 415 couples in which one partner was HIV-1–positive and one was initially HIV-1–negative and followed them prospectively for up to 30 months. The incidence of HIV-1 infection per 100 person-years among the initially seronegative partners was examined in relation to behavioral and biologic variables. Results The male partner was HIV-1–positive in 228 couples, and the female partner was HIV-1–positive in 187 couples. Ninety of the 415 initially HIV-1–negative partners seroconverted (incidence, 11.8 per 100 person-years). The rate of male-to-female transmission was not significantly different from the rate of female-to-male transmission (12.0 per 100 person-years vs. 11.6 per 100 person-years). The incidence of seroconversion was highest among ...
2,897 citations
TL;DR: A theoretical strategy of universal voluntary HIV testing and immediate treatment with ART, combined with present prevention approaches, could have a major effect on severe generalised HIV/AIDS epidemics.
1,948 citations