Thomas E. Guadamuz
Mahidol University
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Featured researches published by Thomas E. Guadamuz.
Lancet Infectious Diseases | 2013
Stefan Baral; Tonia Poteat; Susanne Strömdahl; Andrea L. Wirtz; Thomas E. Guadamuz; Chris Beyrer
BACKGROUND Previous systematic reviews have identified a high prevalence of HIV infection in transgender women in the USA and in those who sell sex (compared with both female and male sex workers). However, little is known about the burden of HIV infection in transgender women worldwide. We aimed to better assess the relative HIV burden in all transgender women worldwide. METHODS We did a systematic review and meta-analysis of studies that assessed HIV infection burdens in transgender women that were published between Jan 1, 2000, and Nov 30, 2011. Meta-analysis was completed with the Mantel-Haenszel method, and random-effects modelling was used to compare HIV burdens in transgender women with that in adults in the countries for which data were available. FINDINGS Data were only available for countries with male-predominant HIV epidemics, which included the USA, six Asia-Pacific countries, five in Latin America, and three in Europe. The pooled HIV prevalence was 19·1% (95% CI 17·4-20·7) in 11 066 transgender women worldwide. In 7197 transgender women sampled in ten low-income and middle-income countries, HIV prevalence was 17·7% (95% CI 15·6-19·8). In 3869 transgender women sampled in five high-income countries, HIV prevalence was 21·6% (95% CI 18·8-24·3). The odds ratio for being infected with HIV in transgender women compared with all adults of reproductive age across the 15 countries was 48·8 (95% CI 21·2-76·3) and did not differ for those in low-income and middle-income countries compared with those in high-income countries. INTERPRETATION Our findings suggest that transgender women are a very high burden population for HIV and are in urgent need of prevention, treatment, and care services. The meta-analysis showed remarkable consistency and severity of the HIV disease burden among transgender women. FUNDING Center for AIDS Research at Johns Hopkins and the Center for Public Health and Human Rights at the JHU Bloomberg School of Public Health.
American Journal of Public Health | 2011
Mark S. Friedman; Michael P. Marshal; Thomas E. Guadamuz; Chongyi Wei; Carolyn F. Wong; Elizabeth Saewyc; Ron Stall
OBJECTIVES We compared the likelihood of childhood sexual abuse (under age 18), parental physical abuse, and peer victimization based on sexual orientation. METHODS We conducted a meta-analysis of adolescent school-based studies that compared the likelihood of childhood abuse among sexual minorities vs sexual nonminorities. RESULTS Sexual minority individuals were on average 3.8, 1.2, 1.7, and 2.4 times more likely to experience sexual abuse, parental physical abuse, or assault at school or to miss school through fear, respectively. Moderation analysis showed that disparities between sexual minority and sexual nonminority individuals were larger for (1) males than females for sexual abuse, (2) females than males for assault at school, and (3) bisexual than gay and lesbian for both parental physical abuse and missing school through fear. Disparities did not change between the 1990s and the 2000s. CONCLUSIONS The higher rates of abuse experienced by sexual minority youths may be one of the driving mechanisms underlying higher rates of mental health problems, substance use, risky sexual behavior, and HIV reported by sexual minority adults.
Aids and Behavior | 2011
Amy L. Herrick; Sin How Lim; Chongyi Wei; Helen A. Smith; Thomas E. Guadamuz; Mark S. Friedman; Ron Stall
Men who have sex with men experience high rates of psychosocial health problems such as depression, substance use, and victimization that may be in part the result of adverse life experiences related to cultural marginalization and homophobia. These psychosocial health conditions interact to form a syndemic which may be driving HIV risk within this population. However, MSM also evidence great resilience to both the effects of adversity and the effects of syndemics. Investigating and harnessing these natural strengths and resiliencies may enhance HIV prevention and intervention programs thereby providing the additional effectiveness needed to reverse the trends in HIV infection among MSM.
Aids and Behavior | 2009
Ron Stall; Luis Duran; Stephen R. Wisniewski; Mark S. Friedman; Michael P. Marshal; Willi McFarland; Thomas E. Guadamuz; Thomas C. Mills
Attempts to document changing HIV incidence rates among MSM are compromised by issues of generalizability and statistical power. To address these issues, this paper reports annualized mean HIV incidence rates from the entire published incidence literature on MSM from Europe, North America and Australia for the period 1995–2005. Publications that met the entry criteria were coded for region of the world, sampling method and year of study. From these reports, we calculated a mean incidence rate with confidence intervals for these variables. Although no differences in mean incidence rates were found for MSM from 1995 to 2005, HIV incidence rates are lower in Australia than either North America or Europe. We calculated a mean incidence rate of 2.39% for MSM in the United States, which if sustained within a cohort of MSM, would yield HIV prevalence rate of approximately 40% at age 40. These extrapolations overlap published HIV prevalence rates for MSM younger than age 40 in the United States. HIV incidence rates in the 2–3% range will adversely affect the health of gay male communities for decades to come. This analysis suggests that greater attention should be devoted to the question of how best to design prevention interventions that will lower HIV incidence rates among gay men.
Journal of Urban Health-bulletin of The New York Academy of Medicine | 2012
Typhanye Penniman Dyer; Steve Shoptaw; Thomas E. Guadamuz; Michael Plankey; Uyen Kao; David G. Ostrow; Joan S. Chmiel; Amy L. Herrick; Ron Stall
This study analyzed data from a large prospective epidemiologic cohort study among men who have sex with men (MSM), the Multicenter AIDS Cohort Study, to assess syndemic relationships among Black MSM in the cohort (N = 301). We hypothesized that multiple interconnections among psychosocial health conditions would be found among these men, defining syndemic conditions. Constituents of syndemic conditions measured included reported depression symptoms, sexual compulsiveness, substance use, intimate partner violence (IPV), and stress. We found significant evidence of syndemics among these Black men: depression symptoms were independently associated with sexual compulsiveness (odds ratios [OR]: 1.88, 95% CI = 1.1, 3.3) and stress (OR: 2.67, 95% CI = 1.5, 4.7); sexual compulsiveness was independently associated with stress (OR: 2.04, 95% CI = 1.2, 3.5); substance misuse was independently associated with IPV (OR: 2.57, 95% CI = 1.4, 4.8); stress independently was associated with depression symptoms (OR: 2.67, 95% CI = 1.5, 4.7), sexual compulsiveness (OR: 2.04, 95% CI = 1.2, 3.5) and IPV (OR: 2.84, 95% CI = 1.6, 4.9). Moreover, men who reported higher numbers of syndemic constituents (three or more conditions) reportedly engaged in more unprotected anal intercourse compared to men who had two or fewer health conditions (OR: 3.46, 95% CI = 1.4–8.3). Findings support the concept of syndemics in Black MSM and suggest that syndemic theory may help explain complexities that sustain HIV-related sexual transmission behaviors in this group.
Aids and Behavior | 2013
Amy L. Herrick; Ron Stall; Joan S. Chmiel; Thomas E. Guadamuz; Typhanye Penniman; Steven Shoptaw; David G. Ostrow; Michael Plankey
Health disparities research among gay and bisexual men has focused primarily on risk and deficits. However, a focus on resiliencies within this population may greatly benefit health promotion. We describe a pattern of resilience (internalized homophobia (IHP) resolution) over the life-course and its associations with current health outcomes. 1,541 gay and bisexual men from the Multi-Center AIDS Cohort study, an ongoing prospective study of the natural and treated histories of HIV, completed a survey about life-course events thought to be related to health. The majority of men resolved IHP over time independent of demographics. Men who resolved IHP had significantly higher odds of positive health outcomes compared to those who did not. These results provide evidence of resilience among participants that is associated with positive health outcomes. Understanding resiliencies and incorporating them into interventions may help to promote health and well-being among gay and bisexual men.
American Journal of Public Health | 2009
Chongyi Wei; Thomas E. Guadamuz; Ron Stall; Frank Y. Wong
We describe the behavioral characteristics and sexually transmitted disease (STD) prevalence of Chinese men who have sex with men (MSM) (n = 41) from a national probability sample of men (n = 1861). Most MSM were partnered with females (97%) and had a low rate of consistent condom use (7%). More MSM than heterosexual men self-reported a prior STD and risky sexual behaviors. MSM may act as a bridge for HIV transmission to female partners. Targeted interventions may help prevent a generalized HIV epidemic in China.
Aids Care-psychological and Socio-medical Aspects of Aids\/hiv | 2010
Thomas E. Guadamuz; Piyada Kunawararak; Chris Beyrer; Jitrat Pumpaisanchai; Chongyi Wei; David D. Celentano
Abstract This paper reports demographic characteristics, HIV prevalence, and correlates among male sex workers (MSW) in Chiangmai, Thailand. A behavioral assessment survey was included as part of the Thailand Ministry of Public Health HIV sentinel surveillance conducted during June 2003. A sample of 181 MSW from 14 sex establishments around Chiangmai who self-identified as sex workers were interviewed. Non-Thai MSW made up half of the sample (48.6%), with the majority being of Shan ethnicity (64.7%). Thai MSW were significantly more likely to report having had receptive anal intercourse (38.0% vs. 11.8%, p<0.001) and to have higher HIV prevalence than non-Thai MSW (11.8% vs. 3.4%, p<0.001). In multivariate analysis, having one or more than one steady male partner in the past month (Odds Ratio: 5.56, 95% Confidence Intervals: 1.13–27.27 and 8.29, 2.01–34.20, respectively), and being older than 21 years (2.26, 1.04–4.90) were significantly and independently associated with prevalent HIV infection. While Thai MSW had higher HIV prevalence and engage in riskier activities, culturally appropriate education and outreach activities are still needed for the large number of ethnic minority MSW, particularly Shan MSW.
Culture, Health & Sexuality | 2015
Louis Gooren; Tanapong Sungkaew; Erik J. Giltay; Thomas E. Guadamuz
There exists limited understanding of cross-sex hormone use and mental well-being among transgender women and, particularly, among transgender men. Moreover, most studies of transgender people have taken place in the Global North and often in the context of HIV. This exploratory study compared 60 transgender men (toms) with 60 transgender women (kathoeys) regarding their use of cross-sex hormones, mental well-being and acceptance by their family. Participants also completed a dispositional optimism scale (the Life Orientation Test Revised), the Social Functioning Questionnaire and the Short Form Health Survey 36 assessing their profile of functional health and mental well-being. Cross-sex hormones were used by 35% of toms and 73% of kathoeys and were largely unsupervised by health-related personnel. There were no differences in functional health and mental well-being among toms and kathoeys. However, toms currently using cross-sex hormones scored on average poorer on bodily pain and mental health, compared to non-users. Furthermore, compared to non-users, cross-sex hormone users were about eight times and five times more likely to be associated with poor parental acceptance among toms and kathoeys, respectively. This study was the first to compare cross-sex hormone use, functional health and mental well-being among transgender women and transgender men in Southeast Asia.
Aids and Behavior | 2014
Chongyi Wei; Sin How Lim; Thomas E. Guadamuz; Stuart Koe
Abstract Increasing use of the Internet to seek sex partners is accompanied by rising HIV infections among men who have sex with men (MSM) in East and South-East Asia. We examined whether the Internet facilitates greater HIV risk taking among MSM in the region. A cross-sectional sample of 9,367 MSM was recruited via the Internet in 2010. We compared socio-demographic and HIV-related behavioral characteristics among MSM who met sex partners on the Internet only, who met sex partners offline only, and who met sex partners through both. Multinomial logistic regression was used to identify independent correlates that were associated with differences in where participants met their male sex partners. Compared to MSM who met partners offline only, those who met partners online only were less likely to have multiple male sex partners, have paid for sex, have consumed recreational drugs, and have used alcohol before sex. MSM who met partners both online and offline appeared to be the riskiest group that they were more likely to have multiple male sex partners, have engaged in UIAI, and have consumed alcohol before sex. These findings suggest that social networking websites alone do not facilitate greater HIV risk taking among MSM. Rather, they provide additional venues for MSM who already engage in HIV-related high risk behaviors to seek sex partners. The Internet offers incredible opportunities to reach large numbers of MSM in East and South-East Asia for HIV prevention and research. Web-based outreach and prevention activities are needed to reach these men. In addition, mobile and application-based interventions should also be developed and disseminated.