Increase in sexual risk behavior and prevalence of Chlamydia trachomatis among adolescents in Northern Thailand.

BACKGROUND: Monitoring changes in adolescent sexual risk behaviors and sexually transmitted infections is critical for evaluating the effectiveness of human immunodeficiency virus and other prevention programs, but population-based data on adolescents in Thailand are limited. We report findings from 2 cross-sectional surveys conducted in 1999 and 2002 among 15-to 21-year-old vocational students. METHODS: In 1999 and 2002, 1725 and 966 students, respectively, were interviewed using computer-assisted self-interview methods. Urine samples were collected and tested for Chlamydia trachomatis and Neisseria gonorrhoeae by polymerase chain reaction. RESULTS: From 1999 to 2002 C. trachomatis prevalence increased from 3.2% to 7.5% (P <0.001) in women and from 2.5% to 6.0% (P <0.001) in men. There was an increase in the reported mean lifetime number of steady sexual partners among both men (3.4-4.7, P = 0.01) and women (2.5-3.3, P <0.001), and in the mean lifetime number of casual partners among men (1.1-2.1, P <0.001) and women (0.3-1.1, P = 0.04). Reported consistent condom use decreased significantly among women with casual partners (43%-19%, P = 0.03) but not among men (25%-31%, P = 0.31). CONCLUSIONS: Our study identified important increases in the prevalence of chlamydial infection and in sexual risk behaviors among Thai adolescents over a 3-year period. These findings are consistent with other studies suggesting profound social changes are changing norms of adolescent sexual behavior in Thailand, and highlight the need for adolescent sexual health services and prevention programming.

Condom use among vocational school students in Chiang Rai, Thailand.

Condom use and its psychosocial correlates were investigated in a sample of 1,725 male and female vocational students (aged 15-21 years) in northern Thailand. Consistent condom use was relatively infrequent with all partner types (8.0% with recent steady partners, 28.5% with casual partners, and 30.7% with commercial sex partners), and only 24.3% reported condom use at first sex. These findings suggest that condom use, even with commercial partners, is not becoming widely established in the younger generation of Thai youths. Condom use with commercial partners was far below goals established by Thailand's 100% Condom Campaign, which was particularly significant for a population in Thailand's HIV epicenter. Consistent condom use with a steady partner was significantly related to condom use during first sex, which suggests the importance of establishing a "condom habit." Consistent condom use with casual partners was related to never having been pregnant (self or partner). Having used condoms at first sex also was associated with never having been pregnant (self or partner), as well as with a number of background social and psychological factors. Intentions to use condom were highly related to peer norms. Results suggest the importance of addressing peer norms concerning condom use, as well as the role of condoms in effective birth control.

Motorcycle helmet use and related risk behaviors among adolescents and young adults in Northern Thailand.

The objective of this study was to assess the prevalence of not wearing a helmet (unprotected) while riding a motorcycle and associated risk behaviors among adolescents and young adults in Northern Thailand. Participants were 1725 students, aged 15-21 years, from 3 vocational schools in Chiang Rai Province; 51.8% were male. Participants completed a classroom-based computer-assisted self-interview (ACASI). Of men 72.7% and of women 64.4% reported unprotected motorcycle riding 3 times or more in the past week. Logistic regression analysis showed the variables independently associated with unprotected riding to be history of ever riding after having had 3 or more alcoholic drinks (odds ratio (OR) = 2.21, 95% confidence interval (CI) = 1.76-2.21), attending technical school (OR = 2.09, 95% Cl = 1.55-2.83), living with the family (OR = 1.38, 95% CI = 1.10-1.73), and having ever had a traffic accident (OR = 1.20, 95% CI = 1.12-1.29). Being of hill tribe ethnicity (vs Thai lowlander) was associated with protected riding (OR = 0.42, 95% CI = 0.20-0.90). Adolescents and young adults in Chiang Rai are at high risk for riding a motorcycle without a helmet buckled on the head. Public education in combination with enforcement of compulsory helmet use while riding a motorcycle is recommended.

Palmtop-assisted self-interviewing for the collection of sensitive behavioral data: randomized trial with drug use urine testing.

Palmtop-assisted self-interviewing (PASI) may provide a cheaper and more mobile alternative to audio-computer-assisted self-interviewing (ACASI) for collecting sensitive behavioral data. To evaluate PASI, in late 2002 the authors enrolled 1,283 Thai students aged 15-21 years in a randomized trial. Data collection used PASI, ACASI, self-administered questionnaire, and face-to-face interview in combination with drug-use urine testing. By use of reported levels of behaviors and agreement between self-reports of smoking and urine test results, PASI and ACASI (alpha = 0.05) were compared for noninferiority, and PASI and interview were compared for superiority (alpha = 0.05). Noninferiority of PASI was demonstrated by use of self-reports of the most sensitive areas of sexual behavior (e.g., oral sex, sexual intercourse, commercial sex, history of genital ulcers, pregnancy), as well as self-reports of less sensitive behaviors (e.g., alcohol use, dietary behaviors, symptoms of depression). Data generally showed noninferiority of PASI, ACASI, and self-administered questionnaires when compared with each other and superiority of PASI, ACASI, and self-administered questionnaires when compared with interviews. PASI agreements between self-reports of tobacco smoking and presence of nicotine metabolites in urine were noninferior to ACASI and superior to interviews. The establishment of PASI noninferiority and superiority using behavioral and biologic measures suggests that PASI is a scientifically acceptable alternative for collecting sensitive behavioral data.

Inconsistent condom use with steady and casual partners and associated factors among sexually-active men who have sex with men in Bangkok, Thailand.

HIV/STD risk behavior has not been examined in community samples of men who have sex with men (MSM) in Thailand. The sexually-active sample (n=927) was recruited from bars, saunas, and parks; 20% identified as bisexual and 17% tested HIV-positive. Inconsistent (<100%) condom use was reported by 45% of those with steady partners and 21% of those with casual partners in the prior three months. 21% had heard of effective HIV treatments (n=194), among whom 44% believed HIV was less serious and 36% said their risk behavior had increased after hearing about the treatments. In multivariate analysis, HIV-positive status, gay-identification, getting most HIV information from the radio, believing HIV can be transmitted by mosquito bite, and concern about acquiring an STD were associated with inconsistent condom use during anal sex; slightly older age (25-29 vs. 18-24 years) was associated with more consistent condom use. HIV/STD risk-reduction strategies for MSM in Bangkok should clearly state sexual risk to individuals in this population.

High rates of pregnancy among vocational school students: results of audio computer-assisted self-interview survey in Chiang Rai, Thailand.

Unplanned pregnancy among young people can lead to adverse social, psychological, and health outcomes, particularly when it results in abortion. In 1999, we examined the prevalence of and factors associated with pregnancy and abortion among 1725 consenting vocational school students in northern Thailand. Results from an audio computer-assisted self-interview showed that 48% of the male and 43% of the female students reported ever having had sexual intercourse. Among those who had had intercourse, 27% of the women and 17% of the men said they or their partner had ever been pregnant. Among the last reported pregnancies that resulted in delivery or abortion, 95% were aborted. Age, current contraceptive use, early initiation of sexual intercourse (

Risk factors for sexually transmitted diseases in northern Thai adolescents: an audio-computer-assisted self-interview with noninvasive specimen collection.

BACKGROUND: Previous studies of sexual behavior and sexually transmitted diseases (STDs) in Thai adolescents may have been limited by participation bias and underreporting of stigmatized behaviors. GOAL: The goal was to increase knowledge about risk behaviors and STDs among youths in Thailand. STUDY DESIGN: Students aged 15 to 21 years completed an audio-computer-assisted self-interview. Oral fluid was tested for HIV antibodies and urine was tested for Chlamydia trachomatis and Neisseria gonorrhoeae nucleic acids with polymerase chain reaction. RESULTS: Of 1736 invited students, 1725 (99.4%) agreed to participate. Overall, C trachomatis infection was detected in 49 (2.8%), and there were five cases (0.3%) each of infection with N gonorrhoeae and HIV. Among those who reported sexual intercourse, the prevalence of chlamydial infection was 3.7% among men and 6.1% among women. Logistic regression analysis showed age-adjusted factors associated with chlamydial infection among men to be parents' occupation in agriculture, having sold sex, having a sex partner who had been pregnant, and the number of casual sex partners during lifetime. Among women, age-adjusted factors were parents' occupation in agriculture, number of casual partners during lifetime, having an older sex partner, and perception of higher HIV infection risk. CONCLUSION: These adolescents had high rates of unprotected intercourse and are at risk for STDs. Prevention programs should emphasize use of effective contraceptive methods, including condom use; reducing the number of sex partners (stressing the risk a partner of older age may pose to female adolescents); and reducing engagement in commercial sex.

The prevalence of bisexual and homosexual orientation and related health risks among adolescents in northern Thailand.

Homo- or bisexual (HB) adolescents may have greater and different health risks than the population of heterosexual adolescents. We assessed sexual orientation and health risk behaviors in 1,725 consenting 15- to 21-year-old vocational school students in northern Thailand. Data were collected using audio-computer-assisted self-interviewing. Nine percent of males and 11.2% of females identified themselves as homo- or bisexual. HB males had an earlier mean age at sexual debut (14.7 years) and a higher mean number of lifetime sexual partners (7.9) than did heterosexual males (16.8 years and 5.8 partners, respectively). HB males (25.9%) and females (32.2%) were sexually coerced more often than were heterosexual males (4.6%) and females (19.6%). Drug use was reported significantly more frequently by HB females and significantly less frequently by HB males than by their heterosexual counterparts. HB males showed more signs of social isolation and depression than did heterosexual males. We conclude that HB adolescents in northern Thailand are at greater and different health risks than are their heterosexual counterparts. Differential health education messages for HB and heterosexual youth are warranted.