Proinflammatory oscillations over the menstrual cycle drives bystander CD4 T cell recruitment and SHIV susceptibility from vaginal challenge.

BACKGROUND: The menstrual cycle influences HIV infection-risk in women, although the timing and underlying mechanism are unclear. Here we investigated the contribution of the menstrual cycle to HIV susceptibility through evaluating immune behavior with infection-risk over time. METHODS: Blood and vaginal lavage samples were collected from 18 pig-tailed macaques to evaluate immune changes over reproductive cycles, and from 5 additional animals undergoing repeated vaginal exposures to simian HIV (SHIV). Peripheral blood mononuclear cell (PBMC) samples from healthy women (n = 10) were prospectively collected over the course of a menstrual cycle to profile T cell populations. Immune properties from PBMC and vaginal lavage samples were measured by flow cytometry. Plasma progesterone was measured by enzyme immunoassay. The oscillation frequency of progesterone concentration and CCR5 expression on CD4 T cells was calculated using the Lomb-Scargle periodogram. SHIV infection was monitored in plasma by RT-PCR. Immune measures were compared using generalized estimating equations (GEE). FINDINGS: Macaques cycle-phases were associated with fluctuations in systemic immune properties and a type-1 inflammatory T cell response with corresponding CCR5+ memory CD4 T cell (HIV target cell) infiltration into the vaginal lumen at the late luteal phase. Power spectral analysis identified CCR5 oscillation frequencies synchronized with reproductive cycles. In a repetitive low-dose vaginal challenge model, productive SHIV163P3 infection only occurred during intervals of mounting type-1 T cell responses (n = 5/5). Finally, we identify similar type-1 inflammatory T cell responses over the menstrual cycle are occurring in healthy women. INTERPRETATION: These data demonstrate that periodic shifts in the immune landscape under menstrual cycle regulation drives bystander CCR5+ CD4 T cell recruitment and HIV susceptibility in the female reproductive tract. FUNDING: This study was supported by the U.S. Centers for Disease Control and Prevention, Atlanta, GA 30329 and NIH grants to Emory University (K23AI114407 to A.N.S., the Emory University Center for AIDS research [P30AI050409], and Atlanta Clinical and Translational Sciences Institute [KLR2TR000455, UL1TR000454]). DISCLAIMER: The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the U.S. Centers for Disease Control and Prevention or the Department of Health and Human Services.

Improvements in Retention in Care and HIV Viral Suppression Among Persons with HIV and Comorbid Mental Health Conditions: Patient-Centered HIV Care Model.

The Patient-centered HIV Care Model (PCHCM) integrated community-based pharmacists with medical providers and required sharing of patient clinical information and collaborative therapy-related action planning. We determined the proportions of participants with HIV and mental health conditions who were retained in care and the proportion virally suppressed, pre- and post-implementation. Overall, we found a relative 13% improvement in both retention [60% to 68% (p = 0.009)] and viral suppression [79% to 90% (p < 0.001)]. Notable improvements were seen among persons triply diagnosed with HIV, mental illness and substance use [+ 36% (50% to 68%, p = 0.036) and + 32% (66% to 86%, p = 0.001) in retention and viral suppression, respectively]. There were no differences in the proportions of persons adherent to psychiatric medications, pre- to post-implementation, nor were there differences in the proportions of persons retained in care or virally suppressed by psychiatric medication adherence, post-implementation. PCHCM demonstrated that collaborations between community-based pharmacists and medical providers can improve HIV care continuum outcomes among persons with mental health conditions.

Retention in HIV Care Among Participants in the Patient-Centered HIV Care Model: A Collaboration Between Community-Based Pharmacists and Primary Medical Providers.

Poor retention in HIV care is associated with higher morbidity and mortality and greater risk of HIV transmission. The Patient-Centered HIV Care Model (PCHCM) integrated community-based pharmacists with medical providers. The model required sharing of patient clinical information and collaborative therapy-related action planning. The proportion of persons retained in care (≥1 medical visit in each 6-month period of a 12-month measurement period with ≥60 days between visits), pre- and post-PCHCM implementation, was modeled using log binomial regression. Factors associated with post-implementation retention were determined using multi-variable regression. Of 765 enrolled persons, the plurality were male (n = 555) and non-Hispanic black (n = 331), with a median age of 48 years (interquartile range = 38-55); 680 and 625 persons were included in the pre- and post-implementation analyses, respectively. Overall, retention improved 12.9% (60.7-68.5%, p = 0.002). The largest improvement was seen among non-Hispanic black persons, 22.6% increase (59.7-73.2%, p < 0.001). Persons who were non-Hispanic black [adjusted risk ratio (ARR) 1.27, 95% confidence interval (CI) 1.08-1.48] received one or more pharmacist-clinic developed action plan (ARR 1.51, 95% CI 1.18-1.93), had three or more pharmacist encounters (ARR 1.17, 95% CI 1.05-1.30), were more likely to be retained post-implementation. In the final multi-variable models, only race/ethnicity [non-Hispanic black (ARR 1.27, 95% CI 1.09-1.48) and "other or unknown" race/ethnicity (ARR 1.36, 95% CI 1.14-1.63)] showed an association with post-implementation retention. PCHCM demonstrated how collaborations between community-based pharmacists and primary medical providers can improve retention in HIV care. This care model may be particularly useful for non-Hispanic black persons who often are less likely to be retained in care.

The association of recent incarceration and health outcomes among HIV-infected adults receiving care in the United States.

Purpose The purpose of this paper is to describe factors associated with incarceration as well as the association between recent incarceration and HIV-related sexual risk behaviors, access to insurance, healthcare utilization (emergency department (ED) and hospital use), antiretroviral therapy (ART) prescription, and viral suppression. Design/methodology/approach Using 2009-2010 data from a cross-sectional, nationally representative three-stage sample of HIV-infected adults receiving care in the USA, the authors assessed the demographic characteristics, healthcare utilization, and clinical outcomes of HIV-infected persons who had been recently incarcerated (detention for>24 hours in the past year) using bivariate analyses. The authors used multivariable logistic regression to examine associations of recent incarceration with insurance status as well as clinical and behavioral outcomes. Findings An estimated 22,949 (95 percent confidence interval (CI) 19,062-26,836) or 5.4 percent (CI: 4.7-6.1) of all HIV-infected persons receiving care were recently incarcerated. Factors associated with recent incarceration were age <50 years, being a smoker, having high school diploma or less, being homeless, income at or below the poverty guidelines, having a geometric mean of CD4 count <500 cells/ µL, and using drugs in the past 12 months. Results from multivariable modeling indicated that incarcerated persons were more likely to use ED services, and to have been hospitalized, and less likely to have achieved viral suppression. Originality/value Recent incarceration independently predicted worse health outcomes and greater use of emergency services among HIV-infected adults currently in HIV care. Options to improve the HIV continuum of care, including pre-enrollment for healthcare coverage and discharge planning, may lead to better health outcomes for HIV-infected inmates post-release.

Evaluation of Sexual Risk Behavior Among Study Participants in the TDF2 PrEP Study Among Heterosexual Adults in Botswana.

OBJECTIVE: Among participants of a clinical trial to test the efficacy of tenofovir/emtricitabine in protecting heterosexual men and women living in Botswana from HIV infection, the aim was to determine (1) if sexual risk behavior, specifically condomless sex acts and number of sex partners, changed over time, (2) factors associated with condomless sex acts and number of sex partners, and (3) the effect of participant treatment arm perception on risk behavior to address the possibility of risk compensation. METHODS: A longitudinal modeling of rates of risk behaviors was used to determine if the rate of condomless sex acts (#acts/person) and rate of sex partners (#partners/person) changed over time and which factors were associated with behavior change. RESULTS: One thousand two hundred participants were analyzed over 1 year. There was a 25% decrease in the rate of sex partners among participants sexually active in the last 30 days. The rate of reported condomless sex acts was greater for males [rate ratio (RR) = 1.34; confidence interval (CI): 1.07 to 1.67] and participants whose sexual debut in years was ≤15 years of age (RR = 1.65; CI: 1.14 to 2.38) and 16-17 (RR = 1.68; CI: 1.22 to 2.31) compared with those ≥20 years. Rate of reported sex partners was greater for males (RR = 3.67; CI: 2.86 to 4.71) and participants whose age at sexual debut in years was ≤15 (RR = 2.92; CI: 2.01 to 4.22) and 16-17 (RR = 2.34; CI: 1.69 to 3.24) compared with those ≥20. There was no effect of participant treatment arm perception on risk behavior. CONCLUSIONS: Our study of preexposure prophylaxis to prevent HIV infection found no evidence of risk compensation which may have been due to participants' motivations to reduce their risk behaviors and risk-reduction counseling.

Investigation of HIV Incidence Rates in a High-Risk, High-Prevalence Kenyan Population: Potential Lessons for Intervention Trials and Programmatic Strategies.

Cost-effective HIV prevention programs should target persons at high risk of HIV acquisition. We conducted an observational HIV incidence cohort study in Kisumu, Kenya, where HIV prevalence is triple that of the national rate. We used referral and venue-sampling approaches to enroll HIV-negative persons for a 12-month observational cohort, August 2010 to September 2011, collected data using computer-assisted interviews, and performed HIV testing quarterly. Among 1292 eligible persons, 648 (50%) were excluded for HIV positivity and other reasons. Of the 644 enrollees, 52% were women who were significantly older than men (P<.01). In all, 7 persons seroconverted (incidence rate [IR] per 100 person-years=1.11; 95% confidence interval [CI] 0.45-2.30), 6 were women; 5 (IR=3.14; 95% CI 1.02-7.34) of whom were ≤25 years. Most new infections occurred in young women, an observation consistent with other findings in sub-Saharan Africa that women aged ≤25 years are an important population for HIV intervention trials in Africa.

Measuring the potential role of frailty in apparent declining efficacy of HIV interventions.

OBJECTIVE: In recent HIV intervention trials, intervention efficacies appear to decline over time. Researchers have attributed this to "waning," or a loss of intervention efficacy. Another possible reason is heterogeneity in infection risk or "frailty." We propose an approach to assessing the impact of frailty and waning on measures of intervention efficacy and statistical power in randomized-controlled trials. METHODS: Using multiplicative risk reduction, we developed a mathematical formulation for computing disease incidence and the incidence rate ratio (IRR) as a function of frailty and waning. We designed study scenarios, which held study-related factors constant, varied waning and frailty parameters and measured the change in disease incidence, IRR, and statistical power. RESULTS: We found that frailty alone can impact disease incidence over time. However, frailty has minimal impact on the IRR. The factor that has the greatest influence on the IRR is intervention efficacy and the degree to which it is projected to wane. We also found that even moderate waning can cause an unacceptable decrease in statistical power while the impact of frailty on statistical power is minimal. DISCUSSION: We conclude that frailty has minimal impact on trial results relative to intervention efficacy. Study resources would, therefore, be better spent on efforts to keep the intervention efficacy constant throughout the trial (e.g., enhancing the vaccine schedule or promoting treatment adherence).

HIV-Related Mortality Among Adults (≥ 18 years) of Various Hispanic or Latino Subgroups--United States, 2006-2010.

Hispanics or Latinos residing in the USA are disproportionately affected by HIV when compared to whites. Health outcomes for Hispanics or Latinos diagnosed with HIV infection may vary by Hispanic or Latino subgroup. We analyzed national mortality data from the National Center for Health Statistics for the years 2006 to 2010 to examine differences in HIV-related mortality among Hispanics or Latinos by sociodemographic factors and by Hispanic or Latino subgroup. After adjusting for age, HIV-related death rates per 100,000 population were highest among Hispanics or Latinos who were male (45.6, 95 % confidence interval [CI], 44.4 to 46.9) compared to female (12.0, 95 % CI 11.4 to 12.6), or resided in the Northeast (75.1, 95 % CI 72.2 to 77.9) compared to other US regions at the time of death. The age-adjusted HIV-related death rate was highest among Puerto Ricans (100.9, 95 % CI 97.0 to 104.8) and lowest among Mexicans (16.9, 95 % CI 16.2 to 17.6). Among all deaths, the proportion of HIV-related deaths was more than four times as high among Puerto Ricans (adjusted prevalence ratio = 4.3, 95 % CI 4.1 to 4.5) compared to Mexicans. To ensure better health outcomes for Hispanics or Latinos living with HIV in the USA, medical care and treatment programs should be adapted to address the needs of various Hispanic or Latino subgroups.

Men who have sex with men in Kisumu, Kenya: comfort in accessing health services and willingness to participate in HIV prevention studies.

Men who have sex with men (MSM) are a crucial and marginalized at risk population for HIV in Africa but are poorly studied. Like other areas of Africa, homosexuality is illegal in Kenya. We assessed MSM comfort in accessing health services and willingness to participate in HIV prevention research in Kisumu, Kenya-an area of high HIV prevalence. We conducted a two-phase formative study with individual interviews (n = 15) and a structured survey (n = 51). Peer contact or snowball method (n = 43, 84.3%) was the primary recruitment strategy used to locate MSM. Exact logistic regression models were used for survey data analysis. Over 60% (32/51) of survey participants were not very comfortable seeking health services from a public hospital. Almost all MSM (49/51; 96.1%) reported willingness to be contacted to participate in future HIV research studies. Efforts to provide facilities that offer safe and confidential health services and health education for MSM is required. Continued community engagement with the MSM population in Kenya is needed to guide best practices for involving them in HIV prevention research.

Incidence of opportunistic illness before and after initiation of highly active antiretroviral therapy in children.

BACKGROUND: Little is known about immune reconstitution inflammatory syndrome in children in the United States. METHODS: LEGACY is a longitudinal cohort study of HIV-infected participants 0-24 years at enrollment during 2005 to 2007 from 22 US clinics. For this analysis, we included participants with complete medical record abstraction from birth or time of HIV diagnosis through 2006. Opportunistic illness (OI) included AIDS-defining conditions and selected HIV-related diagnoses. We calculated the incidence (#/100 patient-years) of OI diagnosed in the months pre- and postinitiation of the first highly active antiretroviral therapy (HAART) regimen which was followed by ≥1 log reduction in HIV viral load. We defined OI as immune reconstitution inflammatory syndrome if an OI incidence increased after HAART initiation. "Responders" were defined as experiencing ≥1 log decline in viral load within 6 months after HAART initiation. RESULTS: Among 575 patients with complete chart abstraction, 524 received HAART. Of these 524 patients, 343 were responders, 181 were nonresponders and 86 experienced OI. Responders accounted for 98 of 124 (79%) of OI. Pre-HAART and post-HAART OI incidences were 43.7 and 24.4 (P = 0.003), respectively, among responders and 15.9 and 9.1 (P = 0.2), respectively, among nonresponders. Overall, OI incidences among responders and nonresponders were 33.8 and 12.3, respectively (P = 0.002). Responders were more likely than nonresponders to experience herpes simplex and herpes zoster before HAART initiation (all, P < 0.002). CONCLUSIONS: The lack of immune reconstitution inflammatory syndrome in participants initiating HAART may be due to low overall OI rates. The unexpectedly higher OI prevalence comprised mainly of herpes simplex and zoster, before HAART initiation among responders, may have motivated them to better adhere to HAART.

Correlates of health attitudes among homosexual and bisexual men.

There is increased emphasis on physician attention to the overall health and wellness of homosexual and bisexual men, though little is known about the health-related attitudes of these groups. This study determined factors associated with the health attitudes of homosexual and bisexual men and identified preferred sources of health information. For this study, the 2008 ConsumerStyles panel survey was used to create three health attitude scales and to determine factors associated with each scale. The three scales were labeled: (1) health motivation; (2) relationship with health care provider; and (3) self-perception of health literacy. In addition to other factors, higher scores for health motivation and relationship with health care provider were associated with black compared with white men. In contrast, lower scores for self-perception of health literacy were associated with black compared with white men. For information on an unfamiliar health condition, most homosexual and bisexual men chose the Internet. Black homosexual and bisexual men reported being motivated to be healthy and working well with their health care provider to manage their health. However, their perception of their own health literacy [corrected] was low compared with the white men. Attempts to improve health literacy through Internet sites may be helpful in improving health attitudes and reducing negative health outcomes.

Men who have sex with men in Kisumu, Kenya: support group membership and knowledge of HIV-risk factors.

Men who have sex with men are an important yet marginalised population for HIV prevention in Africa. We conducted a two-phase study (individual qualitative interviews and a survey) of men who have sex with men, aged 18-34 years of age and living in Kisumu, Kenya. Approximately half (27/51) of survey respondents reported belonging to a support group. The odds of belonging to support groups were greater for older men (aged 24-34 versus 18-23 years [OR = 5.20; 95% CI = 1.27-26.66]). More than two-thirds (68.6%) of survey respondents were categorised as having high knowledge of HIV-risk factors. Most respondents (94.1%) correctly reported lack of condom use during vaginal sex as a risk factor for HIV, but slightly fewer (82.4%) recognised lack of condom use during anal sex as an HIV risk factor. Among the 15 interviewees, the following were included as greatest needs: health information (n = 5), safe lubricants (n = 5), condoms (n = 4), healthcare facility or men-who-have-sex-with-men-friendly health services (n = 3) and advocacy (n = 2). Kenyan men who have sex with men have developed support groups and have unmet needs for information, lubricants and condoms and services. Partnering with support groups offers an opportunity for organisations to reach men who have sex with men with accurate health information, provision of safe sexual lubricants, condoms and other health and social services.

Patterns of condom use among students at historically Black colleges and universities: implications for HIV prevention efforts among college-age young adults.

Over 1.1 million Americans are living with human immunodeficiency virus (HIV), and African-American youth and young adults are disproportionately affected. Condoms are the most effective prevention tool, yet data regarding condom use patterns for African-American college youth are lacking. To inform and strengthen HIV prevention strategies with African-American college-age youth, we surveyed students attending 24 historically Black colleges and universities regarding condom use patterns. Students were administered anonymous questionnaires online to explore knowledge, attitudes, and practices related to condom use during last sexual intercourse (LSI). Among 824 sexually active respondents (51.8% female, median age 20 years, 90.6% heterosexuals), 526 (63.8%) reported condom use during LSI. Students who used condoms for disease prevention, whose mothers completed high school or had some college education or completed college were more likely to have used a condom during LSI. Spontaneity of sexual encounters, not feeling at risk of HIV, and partner-related perceptions were associated with condom non-use during LSI (p<0.05). Over a third of our college youth sample did not use a condom during LSI and may benefit from increased condom education efforts. These efforts should highlight condoms' effectiveness in protection from HIV. Future HIV education and prevention strategies with similar groups of young adults should explore the implications of maternal education, clarify perceptions of HIV risk, and consider strategies that increase consistent condom use to interrupt sexual transmission of HIV.

HIV/AIDS knowledge scores and perceptions of risk among African American students attending historically black colleges and universities.

OBJECTIVE: African American young adults are disproportionately affected by the HIV/AIDS epidemic and often unaware of their personal risk for HIV. Historically black colleges and universities (HBCUs) enroll 25% of college-educated African American young adults and can play an important role in HIV prevention. We examined HIV/AIDS knowledge of students at HBCUs to inform and strengthen our HIV prevention efforts at HBCUs. METHODS: African American undergraduate HBCU students completed online surveys assessing HIV/AIDS knowledge and behaviors, and we analyzed data to assess their knowledge and behaviors. RESULTS: A total of 1,051 of 1,230 surveys completed (85.4%) were analyzable. Eighty-two percent of students had average/high HIV knowledge scores. Seventy-nine percent of students surveyed perceived themselves to be at low risk for HIV infection; 64% of those who had at least two or more sex partners had not used a condom at last sex encounter. In the final model, significant independent effects were identified for average/high knowledge of HIV risk, including agreeing with assessing a potential partner's HIV risk by all of the five actions listed (adjusted odds ratio [AOR] = 2.7, 95% confidence interval [CI] 1.7, 4.3) and never using a needle to inject drugs (AOR=5.6, 95% CI 3.2, 9.7). CONCLUSIONS: Educating students about effectively assessing sex partner risk will improve HIV knowledge and prevention efforts at HBCUs.

Missed opportunities for HIV testing in health care settings among young African American men who have sex with men: implications for the HIV epidemic.

Limited health care access and missed opportunities for HIV and other sexually transmitted infection (STI) education and testing in health care settings may contribute to risk of HIV infection. In 2008, we conducted a case-control study of African American men who have sex with men (MSM) in a southeastern city (Jackson, Mississippi) with an increase in numbers of newly reported HIV cases. Our aims were to evaluate associations between health care and HIV infection and to identify missed opportunities for HIV/STI testing. We queried 40 potential HIV-infected cases and 936 potential HIV-uninfected controls for participation in this study. Study enrollees included HIV-infected cases (n=30) and HIV-uninfected controls (n=95) who consented to participate and responded to a self-administered computerized survey about sexual risk behaviors and health care utilization. We used bivariate analysis and logistic regression to test for associations between potential risk factors and HIV infection. Cases were more likely than controls to lack health insurance (odds ratio [OR]=2.5; 95% confidence interval [CI]=1.1-5.7), lack a primary care provider (OR=6.3; CI=2.3-16.8), and to not have received advice about HIV or STI testing or prevention (OR=5.4; CI=1.3-21.5) or disclose their sexual identity (OR=7.0; CI=1.6-29.2) to a health care provider. In multivariate analysis, lacking a primary health care provider (adjusted odds ratio [AOR]=4.5; CI=1.4-14.7) and not disclosing sexual identity to a health care provider (AOR=8.6; CI=1.8-40.0) were independent risk factors for HIV infection among African American MSM. HIV prevention interventions for African American MSM should address access to primary health care providers for HIV/STI prevention and testing services and the need for increased discussions about sexual health, sexual identity, and sexual behaviors between providers and patients in an effort to reduce HIV incidence and HIV-related health disparities.

Characteristics of first-time and repeat HIV tests among men who have sex with men who test at CDC-supported sites, 2007.

This report describes characteristics of HIV test data for men who have sex with men (MSM) tested in 2007 through programs funded by the Centers for Disease Control and Prevention (CDC). HIV test-level data of MSM submitted by 29 health departments were analyzed to explore test characteristics among all tests, first-time tests, and repeat tests. Characteristics significantly associated with HIV-positive results among first-time tests were identified through logistic regression. Of the 129,893 tests conducted, 18% were first-time tests and 82% were repeat tests. HIV positivity among first-time tests was 4.1% and 3.7% among repeat tests. Among first-time tests, 46% of tests were among White MSM and 48% of HIV-positive test results were among African Americans. An HIV-positive test among first-time tests was strongly associated with being African American, being 40-49 years old, and testing in the southern United States. Race/ethnicity differences exist among MSM testing at CDC-funded sites. African American MSM accounted for the greatest proportion of HIV-positive results but White MSM represented the greatest proportion of tests conducted. HIV prevention strategies that include CDC-funded testing for MSM should increase targeting of African Americans.

Epidemiology of HIV among Asians and Pacific Islanders in the United States, 2001-2008.

BACKGROUND: Recent analyses have shown increases in combined annual HIV diagnosis rates for Asians and Pacific Islanders (API). METHODS: Using surveillance data from 33 states and 4 dependent areas we investigated the epidemiology of HIV among API during 2001-2008. RESULTS: HIV diagnoses for API during 2001-2008 were predominantly among persons age 30-39 years (40%) and males (78%). The primary risk factor for males was sexual contact with males (78%) and for females, heterosexual contact (86%). API were the only racial/ethnic groups with a statistically significant estimated annual percentage increase (4.4%) in HIV diagnoses over the time period. Thirty-seven percent of HIV diagnoses among API progressed to AIDS in <12 months, with significantly greater likelihood among those 30 years and older. Survival was lower among API with AIDS diagnosis after 49 years of age, and was higher among persons with AIDS whose primary risk factor for infection was heterosexual contact. CONCLUSIONS: In contrast to other racial/ethnic groups, API were the only groups to show a significant increase in HIV diagnoses. A clearer understanding of the reasons for this trend is needed, so that appropriate interventions can be selected and adapted to prevent increased HIV prevalence among API in the U.S.

Provision of HIV counseling and testing services at five community-based organizations among young men of color who have sex with men.

In the context of monitoring and improving CDC-funded HIV prevention programs, we describe HIV tests and infections, provision of results, previous HIV tests, and risk behaviors for young (aged 13-29) men of color who have sex with men who received HIV tests at five community-based organizations. Of 1,723 tests provided, 2.1% were positive and 75.7% of positives were previously unaware of their infection. The highest positivity rate was among men aged 25-29 (4.7%). Thirty-four percent of tests were provided to men who were tested for the first time. Over half the tests (53.2%) were provided to men who reported sex with a person of unknown HIV status, and 34% to men who reported sex with an anonymous partner. Continued and more focused prevention efforts are needed to reach and test young men of color who have sex with men and to identify previously undiagnosed HIV infections among this target population.

Assessing mediation in HIV intervention studies.

OBJECTIVES: A mediator is a psychosocial construct that is targeted by an intervention to bring about behavior change. Recent literature suggests that a widely used approach for assessing mediation, namely the causal steps method, can be severely statistically underpowered. This article describes three standard methods for assessing mediation: causal steps, difference in coefficients, and product of coefficients. We also demonstrate the use of asymmetric confidence limits (ACLs) in testing mediation. METHODS: We compared the results obtained by ACL construction with results obtained based on the causal steps and product of coefficients approaches to analyze data from the Seropositive Urban Men's Intervention Trial. RESULTS: ACL construction uncovered previously unidentified mediating factors. We also identified a marginally significant suppressor, which means that, with regard to this factor, the intervention had effects that were opposite from the desired direction. CONCLUSIONS: ACLs are preferred for this type of analysis because of their statistical power and because they are informative regardless of whether the intervention has a significant effect on the outcome. Furthermore, ACLs present the size of the mediating effect rather than just a binary decision regarding significance.

Characteristics of persons with heterosexually acquired HIV infection, United States 1999-2004.

OBJECTIVES: In the United States a growing proportion of cases of heterosexually acquired HIV infections occur in women and in persons of color. We analyzed the association between race/ethnicity, whether diagnoses of HIV infection and AIDS were made concurrently, and the survival after diagnosis of heterosexually acquired AIDS. METHODS: We used data from 29 states that report confidential name-based HIV/AIDS cases to the Centers for Disease Control and Prevention to calculate estimated annual percentage change in the number of actual diagnoses and analyzed the association between race/ethnicity and concurrent diagnoses of HIV and AIDS. We adjusted for reporting delays and absence of information about HIV risk factors. RESULTS: During 1999 to 2004, diagnoses of heterosexually acquired HIV were made for 52 569 persons in 29 states; 33 554 (64%) were women. Among men and women, 38 470 (73%) were non-Hispanic Black; 7761 (15%), non-Hispanic White; and 5383 (10%), Hispanic. The number of persons with heterosexually acquired HIV significantly increased: 6.1% among Hispanic men (95% confidence interval=2.7, 9.7) and 4.5% among Hispanic women (95% confidence interval=1.8, 7.3). The number significantly decreased (-2.9%) among non-Hispanic Black men. Concurrent HIV and AIDS diagnoses were slightly more common for non-Hispanic Whites (23%) and Hispanics (23%) than for non-Hispanic Blacks (20%). CONCLUSIONS: To decrease the incidence of heterosexually acquired HIV infections, prevention and education programs should target all persons at risk, especially women, non-Hispanic Blacks, and Hispanics.