Thai adaptation and reliability of three versions of the Barratt Impulsiveness Scale (BIS 11, BIS-15, and BIS-Brief).

Long, short, and brief versions of the Barratt Impulsiveness scale (BIS-11, BIS-15, and BIS-Brief) were tested in an adult Thai population. The BIS-11T and BIS-15T were translated, back-translated, and administered to a non-clinical population (n = 305) of native Thai speakers who returned 2 weeks later for re-test. BIS-Brief-T psychometrics were calculated post-hoc. Impulsivity scores were normally distributed for the BIS-11T and BIS-15T, but not BIS-Brief-T. Excellent internal consistency was observed, with Cronbach's alpha coefficients above 0.80 for all translated instruments: BIS-11T (α = 0.86), BIS-15T (α = 0.81), BIS-Brief-T (α = 0.81). A total of 260 participants completed both instruments (85%), with test-retest reliability exceeding r = 0.81. All three instruments were highly correlated (r = 0.83-0.89). Confirmatory factor analysis supports a three factor structure (attention, motor, non-planning) for BIS-15T and two factor structure for BIS-11T. BIS scales can support measurement of a range of impulsivity scores in an adult Thai population, though predictive validity of these scales remains unexplored.

Prevalence estimation of dementia among Thai elderly: a national survey.

OBJECTIVE: To determine the prevalence of dementia and its associated factors among Thai elderly. DESIGN: A one-stage cross-sectional national survey. SETTING: National communities in Thailand. SUBJECTS: 4,048 elderly subjects aged 60 and above. RESULTS: There were 668 (16.5%) elderly with a CMT score below 15. Among these elderly, 132 were dependent as to certain aspects of self-care. According to the definition of dementia used in this one-stage survey design (i.e. subjects with a low CMT score and self-care dependence), 3.3 per cent of Thai elderly (95% confidence interval = 2.7-3.8) were classified as having dementia. After adjusting to geographic and municipal area, the prevalence rate was 3.4 per cent (95% confidence interval = 2.8-4). Age-specific prevalence rate increased dramatically from 1.0 per cent in the 60-64 age-group to 31.3 per cent in the 90+ age-group. The prevalence rate of dementia among Thai elderly found in this study did not differ from the prevalence rates among the elderly in other Asian and developed countries. Using a logistic regression analysis, 3 independent factors associated with dementia were age, literacy (writing) and geographic area. CONCLUSION: With a one-stage survey design for determining the prevalence of dementia, the prevalence rate and age-specific prevalence rate among the Thai elderly did not differ from those found in other Asian and developed countries.

A randomized, open-label, comparative trial of zidovudine plus lamivudine versus zidovudine plus lamivudine plus didanosine in antiretroviral-naive HIV-1-infected Thai patients.

OBJECTIVE: To assess the efficacy and tolerability of a triple nucleoside reverse transcriptase inhibitor combination of zidovudine, lamivudine, and didanosine therapy. DESIGN: A randomized open-label trial. PATIENTS: Antiretroviral-naive HIV-infected patients with CD4+ cell counts of 100 to 500 cells/microl. METHODS: A total of 106 patients were randomly assigned to 300 mg of zidovudine (200 mg for body weight <60 kg) twice daily plus 150 mg of lamivudine twice daily plus 200 mg of didanosine (125 mg for body weight <60 kg) twice daily (n = 53) or to zidovudine plus lamivudine (n = 53) for 48 weeks. MAIN OUTCOME MEASURES: Degree and duration of reduction of HIV-1 RNA load and increase in CD4+ cell counts from baseline and development of drug-related toxicities. RESULTS: At 48 weeks, triple drug therapy showed greater declines in plasma HIV-RNA levels from the beginning of treatment than double drug therapy (1.86 vs. 1.15 log10 copies/ml, respectively; p <.001). The proportions of patients with HIV-RNA <50 copies/ml in an intention-to-treat analysis were 54.7% (29 of 53 patients) and 11.3% (6 of 53 patients) in the triple and double drug therapy, respectively (p =.001). There was no significant difference in increase of CD4 count. CONCLUSION: Triple drug therapy with zidovudine, lamivudine, and didanosine was significantly more effective in inducing sustained immunologic and virologic responses than the double combination of zidovudine and lamivudine.

A randomized, double-blind trial of half versus standard dose of zidovudine plus zalcitabine in Thai HIV-1-infected patients (study HIV-NAT 001). HIV Netherlands Australia Thailand Research Collaboration.

BACKGROUND: Triple combination antiretroviral therapy, recommended as standard of care, is unaffordable for much of the developing world. OBJECTIVES: To establish whether half doses of zidovudine (AZT) and zalcitabine (ddC) are as effective as standard doses in a Thai population with lower body weight than Western populations and predominantly infected with HIV-1 subtype E. METHODS: A group of 116 antiretroviral naive patients, with CD4 cell counts 100-500 x 10(6) cells/l, were randomized to: AZT 200 mg three times daily plus ddC 0.75 mg three times daily versus AZT 100 mg three times daily plus ddC 0.375 mg three times daily and followed-up regularly for 48 weeks. RESULTS: The study enrolled 111 patients: 59 men and 52 women, body weight (mean +/- standard deviation) 56.4 +/- 12.3 kg, mean CD4 cell count 324 x 10(6) cells/l, mean HIV RNA 4.7 log10 copies/ml. There were no significant differences between the two groups. Twelve patients discontinued, including two deaths that were unrelated to study medication. No significant differences in adverse events were seen. Week 48 data for the standard dose and half dose arms, respectively, were mean CD4 cell count increases of 52 and 78 x 10(6) cells/l (P = 0.34), mean plasma HIV-1 RNA reduction of 1.4 and 1.1 log10 copies/ml (P = 0.10), HIV RNA of < 400 copies/ml in 52 and 20%[ (P = 0.001). Participants with higher than mean baseline CD8 cell counts (mean 1062 x 10(6) cells/l) showed greater decline in CD8 cells on standard doses. Further analysis showed improved reduction in HIV RNA (P < 0.0001) and in the percentage with undetectable HIV RNA (P = 0.0137) in the standard dose arm, corrected for baseline HIV RNA, which if < 4.75 log10 copies/ml significantly correlated with HIV RNA < 400 copies/ml at week 48. CONCLUSION: At week 48, the proportion with HIV RNA < 400 copies/ml was significantly higher in the standard dose arm; lower baseline HIV RNA correlated with better HIV RNA outcome at 48 weeks. The arms did not differ in CD4 cell response but standard doses correlated with greater CD8 cell decline.

A randomized, dose-finding study with didanosine plus stavudine versus didanosine alone in antiviral-naive, HIV-infected Thai patients.

OBJECTIVES: To evaluate the safety and efficacy of four different regimens of didanosine (ddI) + stavudine (d4T) in HIV-infected Thais. DESIGN: Prospective, open-label, randomized study. METHODS: Patients were randomized to four regimens of high and low doses of ddI and d4T or to ddI alone. D4T was added to the ddI-alone arm after week 24. The duration of study was 48 weeks. RESULTS: Seventy-eight patients were randomized (mean CD4 cell count, 255 x 10(6)/l; mean plasma HIV-1 RNA; 4.3 log10 copies/ml). In the intent-to-treat analysis, 78% of patients in the pooled combination arms and 20% of the patients in the ddI alone arm (to which d4T was added after 24 weeks) showed plasma HIV-1 RNA < 500 copies/ml at week 24 (P < 0.001), and 59% versus 53% at week 48, respectively. In addition, the proportion of patients with < 50 HIV-1 RNA copies/ml was 13% versus 7% at week 24 (P = 0.5) and 17% versus 20% at week 48 respectively. At week 24, median CD4 cell count increases from baseline were 101 x 10(6)/l in the pooled combination versus 76 x 10(6)/l in the ddI alone arm (P = 0.78). Logistic regression modeling suggested a correlation between receiving high dose ddI and achieving HIV-1 RNA < 500 copies/ml at week 48 (P = 0.07). CONCLUSIONS: The d4T/ddI combination was superior to ddI alone in producing HIV-1 viral suppression. At week 48, > 60% of patients treated with this combination reached HIV-1 RNA levels < 500 copies/ml. Receiving high dose ddI but not d4T may correlate with a better viral suppression.

A randomized, controlled 24-week study of intermittent subcutaneous interleukin-2 in HIV-1 infected patients in Thailand.

OBJECTIVES: To assess the immunological and virological effects, safety profile and feasibility of subcutaneous interleukin-2 (scIL-2) therapy in an HIV-infected Thai population. DESIGN: Seventy-two patients with baseline CD4 cell count of > or = 350 x 10(6)/l and no history of opportunistic infection were randomized to receive antiretroviral therapy plus scIL-2 (scIL-2 group) or antiretroviral therapy alone (control group). scIL-2 was administered at one of three doses for at least 24 weeks. The main measure of treatment efficacy was change in CD4 cell count. RESULTS: The time-weighted mean change in CD4 cell count from baseline to week 24 was + 252 x 10(6)/l for the scIL-2 group compared with + 42 x 10(6)/l for the control group (P< 0.0001). Changes in plasma HIV RNA were not significantly different between the groups over the same time period: there was a 0.83 log10 copies/ml decrease for the scIL-2 group and a 0.70 log copies/ml decrease for the control group (P= 0.362). CONCLUSIONS: This study provides the most extensive experience of scIL-2 therapy in HIV-1 infected women and Asians, and demonstrates the immunological efficacy, tolerability and feasability of scIL-2 therapy in this population. Data from this study were instrumental in guiding the selection of the scIL-2 dosing regimen for ongoing phase III trials.

Thai Red Cross zidovudine donation program to prevent vertical transmission of HIV: the effect of the modified ACTG 076 regimen.

OBJECTIVES: To evaluate the impact of the modified ACTG 076 zidovudine regimen on the risk for vertical HIV transmission. DESIGN: Observational retrospective evaluation of a prospective cohort. SETTING: Thai Red Cross zidovudine donation program to reduce vertical HIV transmission. PATIENTS: HIV-infected Thai women and their offspring. INTERVENTION: The modified regimen consisted of 500 mg zidovudine daily during pregnancy and 300 mg zidovudine every 3 h during labor, taken orally, and 2 mg/kg zidovudine syrup four times daily for 6 weeks to infants. MAIN OUTCOME MEASURES: Only infants with at least 1 HIV DNA polymerase chain reaction (PCR) result at age > or = 4 weeks were included. HIV infection was defined by having at least one positive PCR at age > or = 4 weeks. The transmission rate was calculated. Characteristics of women who did and did not transmit HIV to infants were compared. RESULTS: A total of 2891 women and their infants participated in the program and 726 infants of 719 women were included in the analysis. Forty-three infants were infected. The overall transmission rate was 6.0% (95% confidence interval, 4.4-8.0). There were no differences in maternal characteristics between transmitters and non-transmitters. The transmission rate in women who started zidovudine before 30 weeks' gestation was not significantly different from that in women who started zidovudine at or after 30 weeks' gestation: 5.7 versus 3.3%, respectively. CONCLUSIONS: This modified zidovudine regimen is effective in reducing vertical transmission in a country with predominant subtype E infection. A donation program for preventing vertical HIV transmission can be implemented in developing countries, as in Thailand.

The Asian Pacific Economic Cooperation Emerging Infections Network.

ISSUE: The Asia Pacific Economic Cooperation (APEC) has undertaken an initiative in emerging infections. PROJECT: The APEC Emerging Infections Network project uses collaborative telecommunications tools such as e-mail and a World Wide Web site to bridge the broad geographic expanse and diversity of APEC. Scientists and policymakers share information to effectively combat emerging infectious disease (EID) through surveillance, prevention, research, and control measures. RESULTS: In the project's first year, site visits compiled information on Internet access in selected economies. Information sharing via electronic lists has been successful; feedback suggests that these strategies will become increasingly useful. The Emerging Infections Network (EINet) Web site includes project information, library access, surveillance data, prevention guidelines, and distance learning resources. A pilot effort to promote the secure electronic exchange of surveillance data demonstrated that informal communications may be both preferable and more feasible during the early stages of this project. LESSONS LEARNED: Human networking is as important as technology-based networking in addressing emerging infections. Internet technology in some APEC economies is barely adequate, but is becoming more reliable and accessible. Numerous member economies are eager to be included in project activities.

Evolution of medical services for HIV/AIDS in Thailand.

BACKGROUND: Thailand started the anti-retroviral supply program in 1992 primarily for low income groups. The budget has increased but coverage has decreased due to the large number of cases requesting supply. Rapid advancement of HIV therapy has resulted in higher drug cost which is not affordable to people in developing countries. The cost effectiveness review in 1995, conducted by staff of the World Bank, World Health Organization, and Ministry of Public Health (MOPH), demonstrated high cost with limited benefit. It encouraged program evolution, from "supply for services" to "supply for research". Faced with an expanding AIDS epidemic and economic set back, Thailand has to adapt its program to fit scientific, ethic, and economic situations. ACTIVITIES: The program now extends to (a) adapting current therapeutic regimens, (b) developing new treatment and (c) natural history study of people with HIV/AIDS who receive anti-retrovirals (ARV), anti-opportunistic infections (anti OIs), or alternative care. Laboratory issues, and prevention activities are also included. To allocate an approximately 300 million baht budget each year, participating hospitals were invited to submit proposals for consideration. Proposals were ranked and supported according to scores and research priority. A clinical research network was set up in 1996 and supply was shipped out in 1997 on double combination for 1,200 cases, with triple combination for 40 cases, all in 58 sites. Investigators were trained for Good Clinical Practices (GCP) to reassure data handling quality. Psychological and social support were encouraged through the health system research network. Until 15 Jan 98, 49 proposals were submitted (42 ARV, 1 herbal medicine, 6 pediatrics/perinatals). A working group consisting of local experts from medical schools, and the MOPH together ranked these proposals. Those with high scores received medical supplies while the low scores received technological advice in order to increase their capability to participate in research in the near future. CONCLUSIONS: Central supply encouraged physicians to treat more cases but discouraged their hospitals to set up their own budget. The clinical research network allowed team and infrastructure building up which can be adapted for drug, vaccine trials and observational databases. More training is needed. For other developing countries, Thailand's experiences should be perceived as an example not a model.

Why do HIV-1 subtypes segregate among persons with different risk behaviors in South Africa and Thailand?

PIP: Initial research on the genetic variability of human immunodeficiency virus (HIV)-1 has indicated that HIV-1 envelope subtype B is dominant in Western countries where homosexuality and injecting drug use are the major risk factors, while env subtypes A, C, D, and E predominate in Africa and Asia where most transmission is heterosexual. Data from South Africa and Thailand suggest that, due to limited mixing of population subgroups, largely independent HIV epidemics caused by different genotypic subgroups may co-exist in a given geographic area. On the other hand, the possibility that HIV-1 subtypes differ in transmission efficiency by exposure mode also has some support. For example, subtypes E and C appear to be better adapted to penile-vaginal transmission, while subtypes B, E, and C may be transmitted efficiently through blood. Factors such as sexual mixing patterns (e.g., commercial sex work) and the prevalence of sexually transmitted diseases must also be considered when examining HIV-1 subtype transmission differences. The use of new assays that allow for the accurate measurement of viral levels in plasma, semen, and genital secretions should complement epidemiologic estimates of transmission efficiency for various HIV-1 subtypes.^ieng

Managing HIV with limited medical resources.

Only a small minority of people in the world infected with HIV will receive the benefits of the current advances in medical treatment. Planning is required to ensure that each country provides the best possible care allowed by its health resources. Relatively small amounts of money, if well spent, can go a long way towards reducing suffering and assisting death with dignity.

HIV-1 subtypes and male-to-female transmission in Thailand.

We examined the risk factors for heterosexual transmission of HIV in a case-control study of couples in Thailand. 90 HIV-positive men and their regular sex partners were enrolled at the immune clinic, Chulalongkorn Hospital, where 92% of male index cases had HIV-1 serotype A (subtype E). Most index cases had acquired HIV through sexual intercourse. 95 couples were enrolled at 15 detoxification clinics, where 79% of them had HIV-1 serotype B (subtype B). Most men had acquired HIV through injecting drug use (IDU).

PIP: A case control study was conducted during February 1992-April 1993 in Bangkok, Thailand, among 62 couples of which both partners were HIV seropositive (concordant couples [cases]) and 46 couples of which the man was HIV seropositive and the woman was HIV seronegative. The subjects were patients in the Immune Clinic in Chulalongkorn Hospital and in 15 drug detoxification (IDU) clinics. Couples in the immune clinic were more likely to be HIV seroconcordant than those in the IDU clinics (69% vs. 48%; 67% vs. 27%, after excluding females who were intravenous [IV] drug users; p 0.01). HIV-1 serotype B (subtype B) was more common among men in the IDU clinics while HIV-1 serotype A (subtype E) (79%) was more common among men in the immune clinic (92%). Seroconcordance was much more common when HIV-1 was of serotype A than when it was of serotype B (70% vs. 52%; odds ratio [OR] = 2.1; p 0.05). Further, when the researchers did not include couples of which the woman was an IV drug user, the difference in concordance was even greater (70% vs. 26%, OR = 6.8; p 0.01). These differences in concordance suggest that HIV-1 serotype A may be more efficiently transmitted than HIV-1 serotype B. The multivariate logistic regression analysis showed that independent risk factors of HIV seroconcordance were HIV-1 serotype A of male partners (adjusted OR = 3.1) and history of IV drug use in female partners (AOR = 4.8). HIV-1 subtype E may be linked to a higher risk of heterosexual transmission than subtype B. If so, the predominance of HIV-1 subtype E in Thailand could explain the rapid spread of HIV infection in Thailand.

Outbreak of anthrax in Thailand.

An outbreak of anthrax occurred among 14 persons exposed to the meat of two water buffalo which had died from anthrax, in two neighbouring villages in the northeastern region of Thailand. All but one case had typical eschars or blisters. Three had eaten raw meat; one of them died from gastric anthrax with severe haematemesis. All the others were successfully treated with penicillin. The incubation period varied between two and 11 days. Sporadic outbreaks of human and animal anthrax still occur in Southeast Asia.

Introduction and spread of multi-resistant Shigella dysenteriae I in Thailand.

Outbreaks of Shigella dysenteriae I occurred in northeastern Thailand in the fall of 1986 and again in the spring and fall of 1987 for the first time in over 20 years. The epidemic strain of S. dysenteriae I was resistant to tetracycline, streptomycin, chloramphenicol, and trimethoprim-sulfamethoxazole, but susceptible to ampicillin. Trimethoprim resistance was chromosomally encoded by type I dihydrofolate reductase. In Ubon Province, where 10,000 cases of dysentery were reported, there were 3-5 cases of dysentery per 1,000 residents during the peak months, with 2-5 hospitalizations per 100 cases of reported dysentery. There were 2 deaths among 101 hospitalized, culture-confirmed cases. The overall case-fatality rate among reported cases of dysentery in this province was 0.9%. In contrast to S. flexneri infections, which occurred predominantly among children less than 5 years old, S. dysenteriae I infections occurred in all age groups. The large number of susceptibles appeared to be important in allowing rapid spread of S. dysenteriae I. In 1 village, 46% of 434 villagers reported dysentery; S. dysenteriae I was isolated from 24 out of 81 (30%) individuals cultured. Based on the prevalence of IgG antibody to S. dysenteriae I lipopolysaccharide, it was estimated that 76% of the villagers had been infected.