David R. Holtgrave

Behavioral interventions to reduce risk for sexual transmission of HIV among men who have sex with men.

BACKGROUNDnMen who have sex with men (MSM) remain at great risk for HIV infection. Program planners and policy makers need descriptions of interventions and quantitative estimates of intervention effects to make informed decisions concerning prevention funding and research. The number of intervention strategies for MSM that have been examined with strong research designs has increased substantially in the past few years.nnnOBJECTIVESn1. To locate and describe outcome studies evaluating the effects of behavioral HIV prevention interventions for MSM.2. To summarize the effectiveness of these interventions in reducing unprotected anal sex.3. To identify study characteristics associated with effectiveness.4. To identify gaps and indicate future research, policy, and practice needs.nnnSEARCH STRATEGYnWe searched electronic databases, current journals, manuscripts submitted by researchers, bibliographies of relevant articles, conference proceedings, and other reviews for published and unpublished reports from 1988 through December 2007. We also asked researchers working in HIV prevention about new and ongoing studies.nnnSELECTION CRITERIAnStudies were considered in scope if they examined the effects of behavioral interventions aimed at reducing risk for HIV or STD transmission among MSM. We reviewed studies in scope for criteria of outcome relevance (measurement of at least one of a list of behavioral or biologic outcomes, e.g., unprotected sex or incidence of HIV infections) and methodologic rigor (randomized controlled trials or certain strong quasi-experimental designs with comparison groups).nnnDATA COLLECTION AND ANALYSISnWe used fixed and random effects models to summarize rate ratios (RR) comparing intervention and control groups with respect to count outcomes (number of occasions of or partners for unprotected anal sex), and corresponding prevalence ratios (PR) for dichotomous outcomes (any unprotected anal sex vs. none). We used published formulas to convert effect sizes and their variances for count and dichotomous outcomes where necessary. We accounted for intraclass correlation (ICC) in community-level studies and adjusted for baseline conditions in all studies. We present separate results by intervention format (small group, individual, or community-level) and by type of intervention delivered to the comparison group (minimal or no HIV prevention in the comparison condition versus standard or other HIV prevention in the comparison condition). We examine rate ratios stratified according to characteristics of participants, design, implementation, and intervention content. For small group and individual-level interventions we used a stepwise selection process to identify a multivariable model of predictors of reduction in occasions of or partners for unprotected anal sex. We used funnel plots to examine publication bias, and Q (a chi-squared statistic with degrees of freedom = number of interventions minus 1) to test for heterogeneity.nnnMAIN RESULTSnWe found 44 studies evaluating 58 interventions with 18,585 participants. Formats included 26 small group interventions, 21 individual-level interventions, and 11 community-level interventions. Sixteen of the 58 interventions focused on HIV-positives. The 40 interventions that were measured against minimal to no HIV prevention intervention reduced occasions of or partners for unprotected anal sex by 27% (95% confidence interval [CI] = 15% to 37%). The other 18 interventions reduced unprotected anal sex by 17% beyond changes observed in standard or other interventions (CI = 5% to 27%). Intervention effects were statistically homogeneous, and no independent variable was statistically significantly associated with intervention effects at alpha=.05. However, a multivariable model selected by backward stepwise elimination identified four study characteristics associated with reduction in occasions of or partners for unprotected anal sex among small group and individual-level interventions at alpha=.10. The most favorable reductions in episodes of or partners for unprotected anal sex (33% to 35% decreases) were observed among studies with count outcomes, those with shorter intervention spans (<=1 month), those with better retention in the intervention condition than in the comparison condition, and those with minimal to no HIV prevention intervention delivered to the comparison condition. Because there were only 11 community-level studies we did not search for a multivariable model for community-level interventions. In stratified analyses including only one variable at a time, the greatest reductions (40% to 54% decreases) in number of episodes of or partners for unprotected anal sex among community-level interventions were observed among studies where groups were assigned randomly rather than by convenience, studies with shorter recall periods and longer follow-up, studies with more than 25% non-gay identifying MSM, studies in which at least 90% of participants were white, and studies in which the intervention addressed development of personal skills.nnnAUTHORS CONCLUSIONSnBehavioral interventions reduce self-reported unprotected anal sex among MSM. These results indicate that HIV prevention for this population can work and should be supported. Results of previous studies provide a benchmark for expectations in new studies. Meta-analysis can inform future design and implementation in terms of sample size, target populations, settings, goals for process measures, and intervention content. When effects differ by design variables, which are deliberately selected and planned, awareness of these characteristics may be beneficial to future designs. Researchers designing future small group and individual-level studies should keep in mind that to date, effects of the greatest magnitude have been observed in studies that used count outcomes and a shorter intervention span (up to 1 month). Among small group and individual-level studies, effects were also greatest when the comparison condition included minimal to no HIV prevention content. Nevertheless, statistically significant favorable effects were also seen when the comparison condition included standard or other HIV prevention content. Researchers choosing the latter option for new studies should plan for larger sample sizes based on the smaller expected net intervention effect noted above. When effects differ by implementation variables, which become evident as the study is conducted but are not usually selected or planned, caution may be advised so that future studies can reduce bias. Because intervention effects were somewhat stronger (though not statistically significantly so) in studies with a greater attrition in the comparison condition, differential retention may be a threat to validity. Extra effort should be given to retaining participants in comparison conditions. Among community-level interventions, intervention effects were strongest among studies with random assignment of groups or communities. Therefore the inclusion of studies where assignment of groups or communities was by convenience did not exaggerate the summary effect. The greater effectiveness of interventions including more than 25% non-gay identifying MSM suggests that when they can be reached, these men may be more responsive than gay-identified men to risk reduction efforts. Non-gay identified MSM may have had less exposure to previous prevention messages, so their initial exposure may have a greater impact. The greater effectiveness of interventions that include efforts to promote personal skills such as keeping condoms available and behavioral self-management indicates that such content merits strong consideration in development and delivery of new interventions for MSM. And the finding that interventions were most effective for majority white populations underscores the critical need for effective interventions for MSM of African and Latino descent. Further research measuring the incidence of HIV and other STDs is needed. Because most studies were conducted among mostly white men in the US and Europe, more evaluations of interventions are needed for African American and Hispanic MSM as well as MSM in the developing world. More research is also needed to further clarify which behavioral strategies (e.g., reducing unprotected anal sex, having oral sex instead of anal sex, reducing number of partners, avoiding serodiscordant partners, strategic positioning, or reducing anal sex even with condom use) are most effective in reducing transmission among MSM, the messages most effective in promoting these behaviors, and the methods and settings in which these messages can be most effectively delivered.

Social capital, poverty, and income inequality as predictors of gonorrhoea, syphilis, chlamydia and AIDS case rates in the United States

Background: Social capital has been related to a number of important public health variables such as child welfare, mortality, and health status. However, the relation of social capital to infectious diseases has received relatively little attention. The relation of social capital to health measures is often posited to be related to the key societal variables of poverty and income inequality. Therefore, any exploration of the correlation between social capital and infectious diseases should also include examination of the association with poverty and income inequality. Objective: This study examined the state level association between social capital, poverty, income inequality, and four infectious diseases that have important public health implications given their long term sequelae: gonorrhoea, syphilis, chlamydia, and AIDS. Method: A state level, correlational analysis (including bivariate linear correlational analysis, and multivariate linear stepwise regression analysis) was carried out. 1999 state level rates of gonorrhoea, syphilis, chlamydia, and AIDS were the main outcome measures. Results: In bivariate analyses, poverty was significantly correlated with chlamydia; income inequality was significantly correlated with chlamydia and AIDS case rates; and social capital was significantly correlated with all outcome measures. In stepwise multiple regression analyses, social capital was always the strongest predictor variable. Conclusions: These results suggest that social capital is highly predictive of at least some infectious diseases. The results indicate the need for further research into this relation, and suggest the potential need for structural interventions designed to increase social capital in communities.

Social Capital as a Predictor of Adolescents' Sexual Risk Behavior: A State-Level Exploratory Study

This exploratory study assessed the state-level association between social capital, poverty, and income inequality and adolescents sexual risk and protective behaviors. A cross-sectional design using state-level correlations was employed. Seven outcome measures from the national 1999 Youth Risk Behavior Surveillance Survey were used. For females and males, social capital was significantly associated with five of the seven outcome measures (all associations p < 01). For females, the amount of variance explained by these correlations ranged from 23% to 45%; the range for males was 20% to 52%. Poverty was not a significant predictor of any outcome variable. Income inequality was a significant predictor of birth control usage among females, but in multivariate regression analyses, only social capital retained significance. Findings provide preliminary evidence that social capital may have a profound influence of adolescents sexual risk and protective behaviors. Social capital was inversely correlated with sexual risk behaviors and positively correlated with protective sexual behaviors. Further and more comprehensive research involving social capital and adolescents is warranted.

Cost comparison of three HIV counseling and testing technologies

BACKGROUNDnIn the United States, more than 2 million human immunodeficiency virus (HIV) antibody tests are performed annually at publicly funded HIV counseling and testing (CT) clinics. Clients do not receive results from one third of these tests because of low return rates. New rapid-testing technologies may improve receipt of results, but no study has systematically analyzed the costs of these newer technologies compared with the standard protocol.nnnOBJECTIVEnTo estimate and compare the economic costs associated with three HIV CT protocols: the standard protocol and the one-step and two-step rapid protocols.nnnMETHODSnA cost analysis model was developed in 2002 to calculate the intervention costs for HIV CT services with the standard CT protocol and the one-step and two-step rapid-test protocols for a hypothetical client in a publicly funded HIV clinic. Sensitivity analyses were performed to ascertain the effects of uncertainty in the model parameters.nnnRESULTSnThe one-step rapid protocol was generally the least expensive of the three protocols. The standard protocol cost less than the two-step protocol per HIV-positive client notified of his or her HIV status, but cost more per HIV-negative client. The sensitivity analysis indicated overlap in the cost estimates for HIV-negative clients, reflecting the generally similar costs of the three testing protocols. Taking into account HIV seroprevalence, the two-step rapid protocol would be less expensive than the standard protocol for most publicly funded testing programs in the United States.nnnCONCLUSIONSnRapid test protocols offer economic advantages as well as convenience, compared to the standard testing protocol. The cost estimates presented here should prove helpful to HIV program managers and other public health decision makers who need information on these counseling and testing technologies.

Using cost-effectiveness league tables to compare interventions to prevent sexual transmission of HIV.

Cost-effectiveness information is needed to help public health decision makers choose between competing HIV prevention programs. One way to organize this information is in a league table that lists cost-effectiveness ratios for different interventions and which facilitates comparisons across interventions. Herein we propose a common outcome measure for use in HIV prevention league tables and present a preliminary league table of interventions to reduce sexual transmission of HIV in the US. Fifteen studies encompassing 29 intervention for different population groups are included in the table. Approximately half of the interventions are cost-saving (i.e. save society money, in the long run), and three-quarters are cost-effective by conventional standards. We discuss the utility of such a table for informing the HIV prevention resource allocation process and delineate some of the difficulties associated with the league table approach, especially as applied to HIV prevention cost-effectiveness analysis.

Associations between internet sex seeking and STI associated risk behaviours among men who have sex with men

Objective: This exploratory study identified associations between internet sex seeking and HIV associated risk behaviours among a high risk sample of men who have sex with men (MSM). Methods: A cross sectional survey of men attending a sex resort was conducted. Of 164 men asked to participate, 91% completed a self administered questionnaire. The questionnaire assessed demographic variables and (using a 3 month recall period) men’s HIV associated sexual risk behaviours. Potential confounding variables were assessed and controlled, as needed, by multivariate analysis. Results: Men currently resided in 14 states. One sixth reported being HIV positive. 57% of the men reported using the internet to seek sex. Differences in critical behaviours (unprotected anal sex and number of partners) were not found. However, compared to those not seeking sex by internet, men using the internet to meet sex partners were more likely to report fisting (adjusted odds ratiou200a=u200a3.3, pu200a=u200a0.04), having group sex (prevalence ratio (PR)u200a=u200a1.2, pu200a=u200a0.0001), using poppers during sex (PRu200a=u200a1.94, pu200a=u200a0.0001), and using ecstasy during sex (PRu200a=u200a2.7, pu200a=u200a0.04). Internet sex seeking men were also significantly more likely to report meeting sex partners in bathhouses (PRu200a=u200a2.2, pu200a=u200a0.0001), bars (PRu200a=u200a1.5, pu200a=u200a0.001), parks (PRu200a=u200a3.2, pu200a=u200a0.006), and circuit parties (PRu200a=u200a8.9, pu200a=u200a0.007). Conclusion: Among MSM attending a sex resort, those using the internet to seek sex partners may have modestly elevated risks for acquiring or transmitting sexually transmitted infections. Subsequent studies should investigate the utility of using the internet as forum for promoting safer sex behaviours among high risk MSM.

Design, measurement, and analytical considerations for testing hypotheses relative to condom effectiveness against non-viral STIs

Recently, the US Department of Health and Human Services (DHHS) issued a report on a workshop that synthesised evidence regarding the effectiveness of latex condoms for the prevention of sexually transmitted infections (STIs).1 The report cited evidence that condoms are effective in preventing HIV transmission and female to male transmission of gonorrhoea, but stated that empirical evidence was insufficient to evaluate the degree of risk reduction provided by condoms with regard to chlamydia, syphilis, chancroid, trichomoniasis, genital herpes, and human papillomavirus. One important implication of the report is that there is a need for further research on condom effectiveness. As the report noted, “to definitively answer the remaining questions about condom effectiveness for preventing STD infections will require well designed and ethically sound clinical studies.”1nnBesides the research perspective, from an applied public health perspective, intensified efforts to test condom effectiveness are urgently needed. Firstly, the DHHS report may have eroded public confidence in an otherwise widely recommended method of STI prevention (see Centers for Disease Control and Prevention, 1996 for public recommendations2). In addition, if confidence in the effectiveness of condoms declines among health professionals and other policy makers, then their efforts to promote condom use also may wane. Consequently, people at risk of STI infection may be less likely to adopt or sustain condom use as a STI prevention strategy.nnGiven the in vitro evidence that intact latex condoms are virtually impermeable to even the smallest of STI pathogens,3–5 the present lack of in vivo evidence supporting condom effectiveness against many STIs should not be counted as evidence that condoms are ineffective. Numerous, complex challenges are inherent in the design and analysis of in vivo tests of condom effectiveness.nnIn this editorial, we describe selected key issues that should be addressed and resolved …

Causes of the decline in AIDS deaths, United States, 1995–2002: prevention, treatment or both?

The decline in AIDS deaths in the USA between 1995 and 2002 has been attributed by Centers for Disease Control (CDC) to HIV treatments advances. The purpose of the present study is to assess whether this AIDS deaths decline was due entirely to treatment advances, to earlier prevention successes, or a combination of both. Secondarily, we quantitatively estimate the number of AIDS deaths averted (or delayed) by treatment advances over and above prevention effects. The study employed scenario analysis to address the research questions. To answer the primary research question, we examined whether three key predictions derived from the shape and peak of the HIV incidence curve in the USA (and the natural history of HIV disease in the era before highly active antiretroviral therapy [HAART]) about the shape and peak of the AIDS deaths curve were upheld (e.g., one prediction was that the peak of the AIDS deaths curve should occur 10–12 years after the peak of the HIV incidence curve). To the extent that these predictions are supported, there is evidence that earlier HIV prevention efforts impacted the number of AIDS deaths later in the epidemic. To answer the second research question, the observed annual AIDS deaths curve (1995–2002) was compared with three estimated AIDS deaths curves that may have occurred had HAART never became available. Three estimations were employed to reflect a range of assumptions about the lag between the flattening of HIV incidence in the USA and the flattening of AIDS deaths (i.e., 10, 11 or 12 years). For any one of the three-scenario analyses, the quantitative area between the observed and estimated AIDS deaths curves provide an estimate of the number of AIDS deaths averted by HIV/AIDS treatments. The three predictions from the HIV incidence curve (and the pre-HAART natural history of HIV disease) for determining the shape and peak of the AIDS deaths curve were supported thereby indicating the influence of past prevention efforts on recent AIDS deaths. However, the observed decline in AIDS deaths was more precipitous than predicted (indicating the influence of treatment advances). The scenario analyses indicated that between 33,480 and 41,784 AIDS deaths were averted (or delayed) between 1995 and 2002 as a function of treatment. That is, approximately, 206,037 AIDS deaths occurred between 1995 and 2002 (in the HAART era), but between 239,517 and 247,821 likely would have occurred without the advent of HAART. We conclude that both past prevention and current treatment services have lead to the AIDS deaths decline in the USA, and that HAART has averted between 33,480 and 41,784 AIDS deaths in the USA between 1995 and 2002 over and above the effects of early prevention efforts.

Differences in HIV risk behaviors among black and white men who have sex with men.

Objectives: Surveillance findings consistently indicate that black men who have sex with men (MSM) experience a disproportionate burden of HIV/AIDS compared with white MSM. This study tested the hypothesis that black MSM engage in greater levels of HIV risk behaviors than white MSM and sought to determine if self-reported HIV serostatus moderated any of the observed differences. Methods: A cross-sectional study of MSM was conducted by recruiting men from gay-identified venues in a large metropolitan area of the southern United States. Data were collected by face-to-face interview. Results: The hypothesis was only supported for one measure of HIV risk behavior: The average number of main (steady) sex partners in the past year was significantly greater among black men (P < 0.0001). However, black and white MSM did not significantly differ in unprotected sex with serodiscordant partners. Racial differences in sexual risk behavior were found only for HIV-negative men and indicated greater protective behavior for black men. Discussion: These findings suggest that fewer black MSM, compared with white MSM, engage in HIV sexual risk behaviors but only among HIV-negative men. Identifying the epidemiologic dynamics driving HIV infection among black MSM that go beyond individual-level risk behaviors may be warranted.

Estimation of annual HIV transmission rates in the United States, 1978-2000.

The HIV/AIDS epidemic in the United States generally has been characterized by AIDS case incidence and AIDS-associated death rates; in a more limited fashion, the epidemic has also been described by AIDS prevalence; population-specific HIV prevalence; and HIV incidence statistics. However, HIV transmission rate information (i.e., the rate of transmission from persons living with HIV to HIV-seronegative persons) has received relatively little attention. The purpose of the present paper is to estimate the annual HIV transmission rate (from HIV-seropositive to HIV-seronegative persons) in the United States for the time period 1978–2000 and to discuss the practical utility of the findings. Using as input annual AIDS-associated deaths and HIV incidence (both variables, especially the latter, contain some element of uncertainty), the model described here finds that HIV transmission rates have dropped dramatically in the United States since the beginning of the epidemic and stayed approximately between 4.00–4.34% during the 1990s. This implies a programmatic success in that for more than roughly 95% of persons living with HIV in any given year, no HIV transmission occurs. Research is urgently needed to fully understand the circumstances that allow the remaining instances of HIV transmission to take place; moreover, serostatus-appropriate HIV-related services are needed to disrupt these remaining instances of transmission.