Patterns of HIV and syphilis infection in Northern Thailand 1998-2001

Northern Thailand has been the epicentre of a largely heterosexually transmitted HIV epidemic that has recently involved married women. In preparation for HIV-prevention trials, we investigated patterns of HIV and syphilis risk through annually measured HIV and syphilis prevalence among northern Thai, peri-urban, community-dwelling men (n=2564) and women (n=3907) aged 18-35 years between 1998 and 2001. Crude HIV and syphilis prevalence were 3.3% and 2.7% for men and 2.3% and 2.1% for women, respectively. In logistic regression models of HIV and syphilis, compared with married men/women, widowers and widows were at increased risk (odds ratio; 95% confidence interval) of syphilis (7.86; 1.56-39.6 and 3.3; 1.14-9.61, respectively) and HIV (12.68; 3.23-49.8 and 41.3; 24.3-70.3, respectively). The oldest women were at lower risk of HIV (0.43; 0.22-0.85). For men and women, those with syphilis were approximately three times more likely to have HIV. These unique population data illustrate evolving sex parity of HIV burden in northern Thailand.     

Cardiac structure and function and arterial circulation in hypertensive patients with and without metabolic syndrome

High blood pressure (BP) is one of the crucial determinants of the metabolic syndrome (MS). The extent to which MS, diagnosed according to the criteria of the International Federation of Diabetes, impacts on cardiovascular organ damage, independently of BP, is debated. Three hundred and forty hypertensive patients and 100 normotensive controls underwent the following procedures: (1) physical examination and resting BP measurements, (2) 24 h ambulatory BP monitoring, (3) laboratory routine examination, (4) echocardiography, (5) carotid ultrasonography and (6) ankle-brachial BP index. The syndrome was found in 104 of the 340 hypertensive patients (30.6). In comparison to those without MS, those with MS had significantly higher prevalence of left ventricular (LV) hypertrophy by mass/height(2.7) criteria (46 vs 42%, P<0.01) but not by LV mass/body surface criteria (30 vs 31%); the ratio between early-to-late peak velocities of the LV filling waves (E/A) was higher (E/A=0.99+/-0.14 vs 0.89+/-0.15, P<0.01) and left atrium was larger (3.8+/-0.3 vs 3.5+/-0.5 cm, P<0.01). Both hypertensive groups had significantly greater LVM and carotid intima-media thickness than normotensives, without between-group-difference. In this hypertension outpatient clinic almost one-third hypertensive patients have MS. They show a deterioration in structure and function of the heart in comparison to hypertensive patients without MS, but no difference was detected in the carotid and peripheral arterial circulation.     

Return to post-test counselling by out-of-treatment injecting drug users participating in a cross-sectional survey in north Vietnam

Return to post-test counselling is essential for optimal individual and public health impact of voluntary counselling and testing (VCT) services. Our study assessed factors associated with return to post-test counselling among 309 out-of-treatment injecting drug users who underwent VCT as part of a cross-sectional survey in Bac Ninh, Vietnam during August and September 2003. The overall return rate to post-test counselling was 54% (n=167). While participants in the rural study district were significantly less likely (chi2=5.8; p<0.05) to return compared with participants in the town centre (42.7 versus 58.1%), return rates did not significantly vary by age, perception of personal HIV risk, HIV serostatus diagnosed by the study, counsellor, history of HIV testing or prior knowledge of HIV status. In a multivariate analysis, higher return rate was associated with residence in Bac Ninh town centre (adjusted OR=1.9; CI=1.1-3.1). Of HIV-positive participants (n=131), 45% (n=59) did not return to collect test results. In view of the findings it is crucial to address risk perception and benefits of collecting test results during pre-test counselling sessions in order to maximize the desired impact of community-based VCT services targeting IDUs in Vietnam.     

Comparison of methods to detect recent HIV type 1 infection in cross-sectionally collected specimens from a cohort of female sex workers in the Dominican Republic

Interest in estimating HIV-1 incidence using specimens obtained as part of cross-sectional surveys has led to the development of new methods to detect recent HIV-1 infection through the testing of a single anti-HIV-positive specimen. These assays are based on quantitative and qualitative differences in anti-HIV-1 antibodies between recent and long-standing infections. An ongoing vaccine preparedness study enrolled female sex workers in the Dominican Republic. Specimens from women found to be HIV positive at baseline were tested for recent HIV-1 infection using the detuned assay, avidity index, and BED-CEIA assay. An unweighted kappa statistic in pairwise comparisons was used to estimate the correlation of recent HIV-1 infection detection by the three methods. Nineteen (3.9%) of 482 women were positive for HIV-1 infection. The incidence of HIV infection was 1.4% [95% confidence interval (CI): 0.2, 5.3], 0.9%(95% CI: 0.1, 4.4), and 1.0%(95% CI: 0.1, 4.4) using detuned assay, avidity index, and BED-CEIA techniques, respectively. The overall agreement between both detuned assay and avidity index and detuned assay and BED-CEIA was 94%(kappa = 0.8, 95% CI; 0.3, 1.0). The correlation was highest between BED-CEIA and avidity index methods (100%; kappa = 1.0). All three methods performed similarly in detecting recent HIV-1 infection in this region dominated by clade B HIV-1 infection. Although incidence estimates were slightly higher using the detuned assay method, they were not significantly different. These assays may be of value in both clinical research and practice. The utility of individual assays for recent infection detection will depend upon operating characteristics, HIV-1 subtype limitations, and selection of appropriate assay cutoff values.     

Patterns of Risky Behaviors Associated with Methamphetamine Use Among Young Thai Adults: A Latent Class Analysis

PurposeMethamphetamine (MA) is the leading illicit drug in Thailand among youth and young adults. Sexual risk behaviors are associated with methamphetamine use, but few data are available on the daily context of methamphetamine use. We developed an inductive behavioral typology that young Thais engage in while using methamphetamine.MethodsWe conducted a cross-sectional study in Chiang Mai, Thailand, in 2005–2006 among 1,162 street-recruited methamphetamine smokers 18–25 years of age. Data collected included sociodemographic characteristics, sexual behaviors, and drug use patterns. Latent class analysis was used to describe patterns of activities in which participants reported engaging directly after using MA. Logistic regression was used to examine univariate correlates of class membership, separately by gender.ResultsParticipants were 75% male with a median age of 19 years. More than half of participants reported frequent alcohol use (≥4 days/week) and half of the sample reported smoking MA ≥2 days/ week. Three classes of activities emerged for male participants (n = 863): “work” (job related); “high-risk behaviors” (motorcycle riding, fighting, sex); and “combined” (all activities). Two classes emerged for the women (n = 299): “work” (housework) and “high-risk behaviors.” “High-risk behaviors” and “combined” (men only) classes were associated with more frequent alcohol and methamphetamine use compared with the “work” class.ConclusionsOur study found a distinct typology of behaviors associated with substance abuse among young adults in Thailand. Behavioral typologies allow a better understanding of the nuances of “risky” behaviors and might prove useful in targeting interventions.     

The efficacy of a network intervention to reduce HIV risk behaviors among drug users and risk partners in Chiang Mai,Thailand and Philadelphia,USA

This HIV Prevention Trials Network study assessed the efficacy of a network-oriented peer education intervention promoting HIV risk reduction among injection drug users and their drug and sexual network members in Chiang Mai, Thailand and Philadelphia, USA. The study was designed to test impact on HIV infection, but the infection rate was low and the study was terminated early. This paper reports efficacy on outcomes of self-reported HIV risk behaviors. We enrolled 414 networks with 1123 participants. The experimental intervention consisted of six small group peer educator training sessions and two booster sessions delivered to the network index only. All participants in both arms received individual HIV counseling and testing. Follow-up visits occurred every six months for up to 30 months. There were 10 HIV seroconversions, 5 in each arm. The number of participants reporting injection risk behaviors dropped dramatically between baseline and follow-up in both arms at both sites. Index members in the intervention arm engaged in more conversations about HIV risk following the intervention compared to control indexes. There was no evidence of change in sexual risk as a result of the intervention. Reductions in injection risk behaviors were observed: 37%, 20%, and 26% reduction in odds of sharing cottons, rinse water and cookers, respectively, and 24% reduction in using a syringe after someone else. Analysis of the individual sites suggested a pattern of reductions in injection risk behaviors in the Philadelphia site. In both sites, the intervention resulted in index injection drug users engaging in the community role of discussing reduction in HIV injection risk behaviors. The intervention did not result in overall reductions in self-reported sexual risk behaviors, and although reductions in injection risk behaviors were observed, the overall efficacy in reducing risk was not established.     

Risk behaviors by audio computer-assisted self-interviews among HIV-seropositive and HIV-seronegative injection drug users.

Audio computer assisted self-interview (ACASI) has been shown to elicit significantly higher reports of sensitive HIV risk behaviors compared with interviewer-administered questionnaires (IAQ). Injection drug users were randomized to either ACASI (n = 556) or IAQ (n = 586) in order to evaluate reporting differences. A significant interaction was found between mode of administration (ACASI/IAQ) and HIV status. HIV-seropositive respondents on ACASI compared with IAQ were less likely to report condom use (odds ratio [OR] = .42, p < .01) and condom use frequency (OR = .28, p < .002), compared with HIV-seronegative respondents. Based on ACASI results, HIV-seropositive individuals engaged in fewer preventive behaviors than suggested by IAQ. These findings support the validity of ACASI as an important mode of data collection in reducing socially desirable responding, especially among HIV-seropositive subjects.