Syphilis incidence among injection drug users by self reported sexual risk behaviour in the past 6 months, Los Angeles County, 1994–6
| Sexual risk behaviours | Cases/total sample | Cases/1000 person years | Rate ratio | 95% CI | p Value |
|---|---|---|---|---|---|
| *IDU men who have sex with men, and bisexual and lesbian IDUs. | |||||
| †Heterosexual IDUs. | |||||
| Overall incidence | 12/390 | 26.0 | — | 19.4, 32.3 | |
| Multiple sex partners: | |||||
| Yes | 7/120 | 50.2 | 3.2 | 1.89, 5.54 | <0.001 |
| No | 5/269 | 15.5 | |||
| Exchanged money/drugs for sex: | |||||
| Yes | 5/55 | 77.7 | 4.4 | 2.76, 7.12 | <0.001 |
| No | 7/335 | 17.5 | |||
| Sexual orientation: | |||||
| Group B* | 4/22 | 187.4 | 10.3 | 7.0, 15.2 | <0.001 |
| Group A† | 8/367 | 18.1 | |||