Validation of the Alcohol, Smoking And Substance Involvement Screening Test (ASSIST).

AIM: The concurrent, construct and discriminative validity of the World Health Organization's Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) were examined in a multi-site international study. PARTICIPANTS: One thousand and 47 participants, recruited from drug treatment (n = 350) and primary health care (PHC) settings (n = 697), were administered a battery of instruments. MEASUREMENTS: Measures included the ASSIST; the Addiction Severity Index-Lite (ASI-Lite); the Severity of Dependence Scale (SDS); the MINI International Neuropsychiatric Interview (MINI-Plus); the Rating of Injection Site Condition (RISC); the Drug Abuse Screening Test (DAST); the Alcohol Use Disorders Identification Test (AUDIT); the Revised Fagerstrom Tolerance Questionnaire (RTQ); and the Maudsley Addiction Profile (MAP). FINDINGS: Concurrent validity was demonstrated by significant correlations between ASSIST scores and scores from the ASI-Lite (r = 0.76-0.88), SDS (r = 0.59), AUDIT (r = 0.82) and RTQ (r = 0.78); and significantly greater ASSIST scores for those with MINI-Plus diagnoses of abuse or dependence (P < 0.001). Construct validity was established by significant correlations between ASSIST scores and measures of risk factors for the development of drug and alcohol problems (r = 0.48-0.76). Discriminative validity was established by the capacity of the ASSIST to discriminate between substance use, abuse and dependence. Receiver operating characteristic (ROC) analysis was used to establish cut-off scores with suitable specificities (50-96%) and sensitivities (54-97%) for most substances. CONCLUSIONS: The findings demonstrated that the ASSIST is a valid screening test for identifying psychoactive substance use in individuals who use a number of substances and have varying degrees of substance use.

Flexible dosing of tincture of opium in the management of opioid withdrawal: pharmacokinetics and pharmacodynamics.

AIMS: The aim was to evaluate the clinical effectiveness, pharmacodynamics and pharmacokinetics of a range of Tincture of Opium (TOP) doses in the management of opioid withdrawal. METHODS: Forty-five opium-dependent Thai subjects were allocated to three dosing groups (6.66, 13.3 and 20 mg morphine equivalents, twice daily) depending on their self-reported prior opium use. On day 5 of dosing subjects underwent an interdosing interval study where blood, withdrawal scores, heart rate and blood pressure (BP) were collected at 0, 1, 3 and 8 h. Plasma morphine concentrations were quantified by high-performance liquid chromatography, and plasma morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) concentrations by LCMS. RESULTS: Thirty-two subjects completed the study. Withdrawal scores were low for all subjects (range 9-23% of maximum response). There were dose-dependent changes in both systolic and diastolic BP (P = 0.021 and P = 0.01, respectively), but these were not considered clinically significant. There were no effects of dose on respiratory rate. Plasma morphine concentrations changed significantly across the interdosing interval (P = 0.0001), rising to a maximum at 1 h after dosing. Plasma morphine concentrations also differed according to dose (P < 0.05). The mean ratios of the morphine glucuronides were found to be: M3G/M6G = 7.7, M3G/morphine = 35.6 and M6G/morphine = 4.9, values comparable to those previously reported. CONCLUSION: The management of opioid withdrawal can be achieved, with minimal adverse effects, by using flexible dosing of TOP.

Identification of CRF34_01B, a second circulating recombinant form unrelated to and more complex than CRF15_01B, among injecting drug users in northern Thailand.

In Thailand, the circulating HIV-1 strains include CRF01_AE, subtype B, and their recombinants. Genotyping and full-genome sequencing had previously identified circulating recombinant form CRF15_01B within a cohort of 347 HIV-1-infected individuals enrolled in the Opiate Users Research (OUR) study in northern Thailand. Using an improved MHAbce in six to eight genome regions and archived OUR serum samples, seven strains were identified with a new and complex 01/B recombinant pattern in common, different from that of CRF15_01B. Complete sequencing of three strains, amplified from serum as overlapping half-genomes, confirmed their common recombinant structure, mostly CRF01_AE, but with segments of subtype B in pol and gp41, plus a region of frequent 01/B crossovers in pol. OUR strains 1969P, 2275P, and 2478P were from individuals without direct epidemiological linkage and thus establish CRF34_01B. More comprehensive HIV-1 prevention and treatment programs in IDU can help to limit the growing complexity of HIV-1 strains in Thailand.

Predictors of mortality among injecting and non-injecting HIV-negative drug users in northern Thailand.

AIMS: To estimate mortality rates among HIV-negative injecting drug users (IDUs) and non-injecting drug users (non-IDUs), and to assess predictors for mortality among the IDUs. DESIGN: Prospective cohort study in northern Thailand with 2-year follow-up. SETTING: IDUs and non-IDUs who were admitted for detoxification treatment for opiate or amphetamine dependence in a regional drug treatment center were screened. After discharge, HIV-negative individuals were followed-up in the community. PARTICIPANTS: A total of 821 HIV-negative drug users [346 IDUs (42%) and 475 non-IDUs, median age = 32; 51% were ethnic minorities]. MEASUREMENTS: All-cause mortality. FINDINGS: There were 33 deaths over 1360 person-years of follow-up. The all-cause mortality rate was 39 per 1000 person-years among IDUs [standardized mortality ratio (SMR) = 13.9], and was 14 per 1000 person-years among non-IDUs (SMR = 4.4). Among male IDUs, the hazards for all-cause deaths were ethnic minority status [adjusted hazard ratio (HR) = 2.9, 95% CI = 1.2-7.2], incident HIV infection (HR = 2.8, 95% CI = 1.1-7.7) and longer duration of drug injection (HR = 1.07, 95% CI = 1.01-1.14). CONCLUSIONS: The mortality among IDUs is high. Being from an ethnic minority, recent HIV acquisition, and a greater number of years of drug injection are predictors of mortality among the IDUs in this region.

Hepatitis C infection among drug users in northern Thailand.

Illicit drug users are commonly infected with hepatitis C virus (HCV) and human immunodeficiency virus (HIV). We evaluated the prevalence, incidence, and risk behaviors associated with HCV infection in 1,859 drug users in northern Thailand. The HCV prevalence was 27.3%: 86.0% among drug injectors (IDUs) and 5.3% among those who did not inject. Sexual behavior was not significantly associated with HCV among IDUs or drug users who used but didn't inject illicit drugs; only injection behaviors were independently associated with HCV in multivariate analysis. Among men, a history and increasing frequency of injecting drugs, older age, and a history of incarceration were associated with HCV infection. Among 514 opiate users who were HCV and HIV seronegative at baseline, 41 incident HCV infections and 6 HIV infections occurred on follow-up; the HCV incidence was 5.43/100 person-years; it was 44.3/100 person-years in IDUs and 1.9/100 person-years in non-injectors. HCV and HIV among drug users in Thailand are common and primarily associated with injection behavior.

Risk factors associated with injection initiation among drug users in Northern Thailand.

BACKGROUND: Circumstances surrounding injection initiation have not been well addressed in many developing country contexts. This study aimed to identify demographic factors, sexual behaviors and drug use characteristics related to injection initiation among drug users in northern Thailand. METHODS: A cross-sectional survey was conducted among 2,231 drug users admitted to the Northern Drug Treatment Center in Mae Rim, Chiang Mai, Thailand, between February 1, 1999 and December 31, 2000. A multiple logistic regression was employed to identify the independent effects from potential risk factors of transition into injection. RESULTS: After controlling for other covariates, being 20 years of age or older, single, ever receiving education, urban residence, and having a history of smoking or incarceration were significantly associated with higher likelihood of injection initiation. Multiple sex partners and an experience of sex abuse were associated with an increased risk of injection initiation. Comparing to those whose first drug was opium, individuals using heroin as their initiation drug had greater risk of injection initiation; conversely, those taking amphetamine as their first drug had less risk of injection initiation. Age of drug initiation was negatively associated with the risk of injection initiation: the older the age of drug initiation, the less the risk of injection initiation. CONCLUSION: Injection initiation was related to several demographic factors, sexual behaviors and drug use characteristics. Understanding these factors will benefit the design of approaches to successfully prevent or delay transition into injection.

High HIV, hepatitis C and sexual risks among drug-using men who have sex with men in northern Thailand.

BACKGROUND: Men who have sex with men (MSM) and who use drugs have shown high HIV risks in Europe, and the Americas. We investigated MSM-drug user demographics, HIV sexual and drug use risks and behaviors in Chiang Mai, northern Thailand to identify prevention targets. METHODS: A total of 2005 males aged 13 years and older were enrolled during inpatient drug treatment from 1999-2000 and assessed for HIV, hepatitis C virus (HCV), syphilis, and for demographics and risks by questionnaire. Data were analyzed using chi and multiple logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Of 2005 males in treatment, 1752 (87.4%) had ever had sex, and 66 of 1752 (3.8%) reported ever having sex with another man; mostly Katoey (transgendered male) partners. MSM had higher HIV rates (OR, 2.32; 95% CI, 1.36-3.96) and were younger (P = 0.002); more likely to be Thai (P < 0.0001); better educated (P < 0.0001); had more lifetime sex partners (P < 0.0001), more female partners (P = 0.002), more female paid partners (P < 0.0001), and been paid for sex (P < 0.0001). MSM were more likely to have ever injected (P < 0.0001), sold drugs, been in prison, injected in prison, used heroin, and to have HCV (OR, 2.59; 95% CI, 1.55-4.34). CONCLUSIONS: Northern Thai MSM-drug users are at high HIV and HCV risk. In addition to sex risks with men, they have more sex with women and sex workers than other men, which fits Thai MSM patterns but not Western ones. Prevention must take into account their high rates of substance use and multiple partner types.

The nature, time course and severity of methamphetamine withdrawal.

AIMS: To characterize the natural history of methamphetamine withdrawal during the first 3 weeks of abstinence. DESIGN: Cross-sectional study with comparison group. Setting A substance use treatment facility in Chiang Mai Province, Thailand. PARTICIPANTS: The sample comprised 21 in-patients undergoing treatment for methamphetamine dependence. Nine age- and sex-matched non-dependent individuals provided comparison data. MEASUREMENTS: Instruments including: the Amphetamine Withdrawal Questionnaire, a modified version of the Cocaine Selective Severity Assessment, Clinical Global Impression scale and the St Mary's Hospital Sleep Questionnaire were completed daily for the first 3 weeks of abstinence. FINDINGS: Methamphetamine withdrawal severity declined from a high initial peak within 24 hours of the last use of amphetamines reducing to near control levels by the end of the first week of abstinence (the acute phase). The acute phase of amphetamine withdrawal was characterized by increased sleeping and eating, a cluster of depression-related symptoms and less severely, anxiety and craving-related symptoms. Following the acute withdrawal phase most withdrawal symptoms remained stable and at low levels for the remaining 2 weeks of abstinence. CONCLUSIONS: This study has provided evidence of a methamphetamine withdrawal syndrome that can be categorized into two phases, the acute phase lasting 7-10 days during which overall symptom severity declined in a linear pattern from a high initial peak, and a subacute phase lasting at least a further 2 weeks.

An effective tool for identifying HIV-1 subtypes B, C, CRF01_AE, their recombinant forms, and dual infections in Southeast Asia by the multi-region subtype specific PCR (MSSP) assay.

The RV144 Thai vaccine trial has been the only vaccine study to show efficacy in preventing HIV infection. Ongoing molecular surveillance of HIV-1 in Southeast Asia is vital for vaccine development and evaluation. In this study a novel tool, the multi-region subtype specific PCR (MSSP) assay, that was able to identify subtypes B, C, CRF01_AE for Thailand, other Southeast Asian countries, India and China is described. The MSSP assay is based on a nested PCR strategy and amplifies eight short regions distributed along the HIV-1 genome using subtype-specific primers. A panel of 41 clinical DNA samples obtained primarily from opiate users in northern Thailand was used to test the assay performance. The MSSP assay provided 73-100% sensitivity and 100% specificity for the three subtypes in each genome region. The assay was then field-tested on 337 sera from HIV infected northern Thai drug users collected between 1999 and 2002. Subtype distribution was CRF01_AE 77.4% (n=261), subtype B 3.3% (n=11), CRF01_AE/B recombinant 12.2% (n=41), CRF01_AE/C recombinant 0.6% (n=2), and non-typeable 6.5% (n=22). The MSSP assay is a simple, cost-effective, and accurate genotyping tool for laboratory settings with limited resources and is sensitive enough to capture the recombinant genomes and dual infections.

The changing molecular epidemiology of HIV type 1 among northern Thai drug users, 1999 to 2002.

CRF01_AE and subtype B have dominated the HIV-1 epidemic in Thailand since 1989. We reported a new circulating recombinant form of HIV-1, CRF15_01B, as well as other unique CRF01_AE/B recombinants among prevalent HIV infections in Thailand. We sought to study this challenging molecular picture through assessment of subtypes among recent HIV-1 seroconverters in northern Thai drug users. A total of 847 HIV-1 seronegative drug users (342 IDU and 505 non-IDU) were enrolled, from 1999 to 2002, in a prospective study; 39 HIV-1 incident cases were identified and characteristics were collected. The overall HIV-1 incidence rate was 2.54/100PY, but it was 10.0/100PY among male IDU. HIV was strongly associated with injection history; 38 of 39 seroconverters gave a history of IDU. A near full-length genome of HIV-1 was recovered by PCR amplification and sequenced from peripheral mononuclear cell extracted DNA of 38 seroconverters. Phylogenetic analysis revealed that 33 (86.8%) were CRF01_AE and 5 (13.2%) were CRF01_AE/B recombinants. These recombinants had different structure but shared some common breakpoints, indicating an ongoing recombination process. Recombinant infection increased with year of sampling (0 to 57.1%). The molecular epidemiology of HIV-1 among drug users in northern Thailand has thus entered a new era. CRF01_AE remains predominant while pure subtype B is becoming rare, and now a substantial component of the epidemic. These findings support the need for CRF01_AE and subtype B components in clade-matched vaccine strategies for Thai phase III trials. Ongoing molecular surveillance of circulating HIV-1 strains is imperative for the evaluation of HIV vaccine efficacy.

A new circulating recombinant form, CRF15_01B, reinforces the linkage between IDU and heterosexual epidemics in Thailand.

HIV-1 subtype B and CRF01_AE have been in circulation in Thailand and Southeast Asia for more than a decade. Initially separated by risk group, the two strains are increasingly intermixed, and two recombinant strains of essentially reciprocal structure have been recently reported. Here we identify additional CRF_01B recombinants and provide the evidence that HIV-1 strains now pass freely between the two high-risk populations. HIV isolates that showed discordance between CRF01_AE and subtype B in multi-region genotyping assays were selected for the study. They were drawn from 3 different cohorts in Thailand representing different risk behaviors and demographic characteristics: a drug user cohort in the north, a family planning clinic attendee cohort in the southeast, and a cohort study of the mucosal virology and immunology of HIV-1 infection in Thailand. The DNA from these isolates was PCR amplified to recover the full HIV-1 genome and subjected to sequencing and phylogenetic analysis. We establish that one particular CRF_01B recombinant, with the external envelope of subtype B and the rest of the genome from CRF01_AE, is circulating widely in Thailand. Termed CRF15_01B (also referred to as CRF15), the strain was primarily heterosexually transmitted, although injecting drug use (IDU) also played a role. In aggregate data from the studies, CRF15 constituted 1.7% of all HIV-1 infections (95% confidence interval 0.5-4.4%) and was dispersed widely in the country. The previously separate heterosexual and IDU epidemics have apparently been bridged by a new CRF. The entry of CRF15 into the mainstream of the epidemic signals new complexity in the long stable molecular picture in Thailand. These recombinants must be considered in ongoing or projected efficacy evaluations of HIV-1 vaccines and antiviral therapies.

Differential seroprevalences of hepatitis C virus, hepatitis B virus and human immunodeficiency virus among intravenous drug users, commercial sex workers and patients with sexually transmitted diseases in Chiang Mai, Thailand.

To elucidate the differences in the mode of transmission of three blood-borne viruses, hepatitis C virus (HCV), hepatitis B virus (HBV) and human immunodeficiency virus (HIV), under comparable conditions of study, we analyzed the prevalences of anti-HCV antibodies (anti-HCV), anti-HBV core antibodies (anti-HBc), HBV surface antigen (HBsAg) and anti-HIV antibodies (anti-HIV) in different risk populations in Chiang Mai, Thailand, where the prevalence of HIV infection is high. The subjects consisted of 98 intravenous drug users (IVDU), 100 commercial sex workers (CSW) and 50 male patients with sexually transmitted diseases (STD). In IVDU the prevalence of anti-HCV was the highest (85%), followed by anti-HBc (77%) and anti-HIV (46%), whereas in CSW and STD the prevalence of anti-HCV was 2 and 0%, respectively, that of anti-HBc 69 and 64%, respectively, and that of anti-HIV 11 and 14%, respectively. The prevalence of anti-HBc minus that of HBsAg, representing horizontal transmission of HBV, was similar for IVDU (63%), CSW (58%) and STD (64%). Thus, HCV is mainly transmitted by blood contact, HIV primarily by blood contact rather than by sexual contact, and HBV equally readily by blood or sexual contact. These findings were supported by the results of logistic regression analysis.

HIV voluntary counseling and testing and HIV incidence in male injecting drug users in northern Thailand: evidence of an urgent need for HIV prevention.

HIV voluntary counseling and testing (VCT), an important strategy for HIV prevention and care, has been available in all government hospitals in Thailand since 1992. We assessed factors associated with HIV testing, its uptake, and estimates of HIV incidence after HIV testing among male northern Thai injecting drug users (IDUs) admitted for inpatient drug treatment. Participants were interviewed about risk behaviors and HIV testing history before VCT was provided as part of the study. Of 825 IDUs who participated, 36% reported a prior HIV test. Factors associated with prior HIV testing in multiple logistic regression analysis included higher education and having >1 lifetime sex partner. Needle sharing was not associated with prior HIV testing. Of the 298 men with a prior test, 80% reported a negative result on their last prior HIV test, of whom 28% tested positive in our study, leading to an estimated incidence rate of 10.2 per 100 person-years. Fifty-nine percent of the IDUs who reported a prior HIV test stated that they did not receive pre- and/or posttest counseling. HIV incidence among IDUs remains high despite having VCT. Extending HIV prevention and harm reduction programs is urgently needed for IDUs in the region.

Comparison of tincture of opium and methadone to control opioid withdrawal in a Thai treatment centre.

AIMS: To evaluate the effectiveness of oral tincture of opium (TOP) and methadone to control opioid withdrawal in patients in northern Thailand. METHODS: Open label, parallel group study in an inpatient facility compared 15 former heroin users receiving methadone 5-20 mg 12 hourly with 15 former opium smokers receiving TOP (3.33-10 mg morphine equivalents 12 hourly). At 0, 1, 3 and 8 h, blood, withdrawal scores and subjective opioid effects were collected. RESULTS: There was a reciprocal association between withdrawal scores/direct subjective opioid effects and plasma (R)-methadone, but not plasma morphine, concentrations. Withdrawal scores at the time of dosing were higher in the TOP patients (9.1 +/- 3) than in the methadone patients (4.5 +/- 4.6) and in the TOP patients were significantly (P = 0.001) attenuated at 3 and 8 h. CONCLUSIONS: At the doses used, TOP was inferior to methadone in suppressing withdrawal. It could prove to be a cost effective and valuable drug, but only after dose size and frequency are further investigated.

Drug use, increasing incarceration rates, and prison-associated HIV risks in Thailand.

BACKGROUND: Incarceration is a known risk for HIV infection in Thai drug users. Through the 1990s, incarceration rates for drug-related offenses rose sharply, whereas HIV prevention and drug treatment in prisons remained limited. METHODS: We assessed HIV and incarceration risks for injection drug users (IDU) and non-IDU in a large treatment center cohort in northern Thailand to investigate HIV and prison risks in this period. We used Thai Bureau of Corrections data to assess incarceration and prevention funds in prisons, 1992-2000. RESULTS: Among 1,865 drug user in the treatment cohort, 503 (27.0%) had ever been jailed. Men (OR 3.3, 95% CI 2.1, 5.2), IDU (OR 6.3, 95% CI 5.1, 7.9), and men who have sex with men (MSM) (OR 3.4, 95% CI 1.8, 6.3) were more likely to have been jailed. Among male IDU who had ever been jailed (N = 272), 15.8% had used drugs in prison. In a multivariate model, incarceration and ever IDU remained independently associated with HIV infection; IDU, MSM behaviors, and harmful traditional practices remained independently associated with having been jailed. From 1992 to 2000, overall alleged narcotics offenses increased from 117,000 to 276,000/year. The number of persons incarcerated for narcotics offenses increased fivefold from 1992 to 1999, from 12,860 to 67,440. For FY 2000, narcotics treatment accounted for 0.06% of the Thai corrections budget, whereas HIV programs in prisons were 0.017%. CONCLUSIONS: Incarceration rates for narcotics offenses have increased sharply in Thailand, whereas prevention has lagged. Having been jailed is an important independent risk for HIV infection among Thai male drug users, especially IDU and MSM. HIV prevention and drug treatment are urgently needed in Thai prisons.

HIV prevalence and risks among injection and noninjection drug users in northern Thailand: need for comprehensive HIV prevention programs.

The authors sought to determine sociodemographic and sexual and drug use risk factors for HIV infection among drug users in northern Thailand adjacent to the Golden Triangle. The authors enrolled patients admitted for inpatient drug detoxification at one treatment center in northern Thailand and studied HIV risks and prevalence using an interviewer-administered questionnaire and serum collection with HIV pretest and posttest counseling. Between February 1, 1999 and January 31, 2000, 1865 patients admitted for opiate and methamphetamine dependence completed study procedures. Overall HIV prevalence was 10.3%: 30.0% among 513 injection drug users (IDUs) and 2.8% among non-IDUs (OR = 14.8, 95% CI: 10.2, 21.6). HIV seroprevalence was 2.4% among exclusive methamphetamine users (98% of whom are non-IDUs) and 3.4% among opium smokers. Injection drug use was the dominant risk factor in multivariate models. Although Thailand is widely recognized as having a successful national response to the heterosexual HIV epidemic, seroprevalence in IDUs remains high. Despite a sharp increase of non-IDUs admitted to the drug treatment center, HIV infection and risks remained high among IDUs in northern Thailand. HIV prevention campaigns need to focus on IDUs and to implement harm reduction strategies to reduce transmission to IDUs and further contain the HIV epidemic in Thailand.