title: Substance use and sexual behaviours of Japanese men who have sex with men: a nationwide internet survey conducted in Japan.
abstract: BACKGROUND
  Japanese men who have sex with men (MSM), especially those living in large metropolitan areas such as Tokyo and Osaka, are facing a growing HIV/AIDS epidemic. Although the Internet is used as a new venue for meeting sex partners, it can also serve as a useful research tool for investigating the risk behaviours of Japanese MSM. This Internet survey explored the extent of substance use and its association with sexual risk behaviours among Japanese MSM.
  
  
  METHODS
  Between 28 February 2003 and 16 May 2003 MSM were recruited through 57 Japanese gay-oriented Web sites, gay magazines, and Internet mailing lists. Participants completed a structured questionnaire anonymously through the Internet.
  
  
  RESULTS
  In total, 2,062 Japanese MSM completed the questionnaire. The average age of participants was 29.0 years and 70.5% identified as gay, 20.8% as bisexual, and 8.7% as other. Overall, 34.5% reported never using a substance, 45% reported ever using one type of substance (lifetime reported single substance users), and 19.6% had used more than 1 type of substance (lifetime reported multiple substance users) in their lifetimes. The substances most commonly used were amyl nitrite (63.2%), 5-methoxy-N, N-diisopropyltryptamine (5MEO-DIPT) (9.3%), and marijuana (5.7%). In the multivariate analysis, unprotected anal intercourse, having had 6 or more sexual partners, visiting a sex club/gay venue in the previous 6 months, a lower education level, and being 30 to 39 years of age were associated with both lifetime single and lifetime multiple substance use. Lifetime reported multiple substance use was also correlated with having a casual sex partner, having symptoms of depression, being diagnosed as HIV-positive, and greater HIV/AIDS-related knowledge.
  
  
  CONCLUSIONS
  This is the first Internet-based research focused on the sexual and substance use behaviours of MSM in Asia. Our findings suggest a compelling need for prevention interventions to reduce HIV risk-related substance use behaviours among Japanese MSM. The results also suggest that the Internet is potentially a useful tool for collecting behavioural data and promoting prevention interventions among this population.
authors.affiliation: Department of Global Health and Socio-epidemiology, Kyoto University School of Public Health Yoshidakonoe-cho, Sakyo-ku, Kyoto 606-8501, Japan. yass@kta.att.ne.jp
authors.forename: Yasuharu
authors.initials: Y
authors.lastname: Hidaka
authors.forename: Seiichi
authors.initials: S
authors.lastname: Ichikawa
authors.forename: Junko
authors.initials: J
authors.lastname: Koyano
authors.forename: Michiko
authors.initials: M
authors.lastname: Urao
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Yasuo
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Kimura
authors.forename: Masako
authors.initials: M
authors.lastname: Ono-Kihara
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kihara
mesh_terms: D008735:5-Methoxytryptamine / Q000031:analogs & derivatives; D000293:Adolescent; D000328:Adult; D000368:Aged; D000680:Amyl Nitrite; D015658:HIV Infections / Q000453:epidemiology / Q000523:psychology*; D007722:Health Knowledge, Attitudes, Practice; D006306:Health Surveys; D018451:Homosexuality, Male / Q000523:psychology* / Q000706:statistics & numerical data; D006801:Humans; D020407:Internet; D007564:Japan; D008297:Male; D002189:Marijuana Abuse; D008875:Middle Aged; D010506:Periodicals as Topic; D012309:Risk-Taking; D019966:Substance-Related Disorders / Q000453:epidemiology / Q000523:psychology*; D011795:Surveys and Questionnaires; D047568:Unsafe Sex / Q000523:psychology* / Q000706:statistics & numerical data
chemical_list: C033696:5-methoxy-N,N-diisopropyltryptamine; D008735:5-Methoxytryptamine; D000680:Amyl Nitrite