Behavioural risk factors for a diagnosis of genital chlamydia/gonorrhoea infection at follow-up among HIV-positive MSM, OHTN Cohort Study, 2010–2013
| Sexual behaviours in preceding 3 months* | Cumulative probability of testing at 12 months (95% CI)† | Cumulative incidence of diagnosis at 12 months (95% CI)† | Unadjusted HR (95% CI) | Multivariable model A‡: adjusted HR (95% CI) | Multivariable model B‡: adjusted HR (95% CI) |
|---|---|---|---|---|---|
| Number of sexual partners | |||||
| None | 15.8 (13.3 to 18.4) | 0.4 (0.0 to 0.8) | Reference | Reference | |
| One | 20.0 (16.7 to 23.3) | 0.7 (0.0 to 1.4) | 2.7 (0.9 to 7.9) | ||
| Two to four | 33.9 (29.7 to 38.1) | 3.0 (1.5 to 4.6) | 10.3 (4.0 to 26.6) | 3.1 (1.4 to 6.6) | |
| Five or more | 42.5 (36.7 to 48.3) | 4.8 (2.4 to 7.3) | 16.0 (6.1 to 41.7) | 3.7 (1.7 to 8.3) | |
| Number of HIV-positive partners | |||||
| None | 19.0 (16.9 to 21.2) | 0.8 (0.3 to 1.2) | Reference | Reference | |
| One | 26.8 (22.2 to 31.4) | 2.2 (0.7 to 3.8) | 2.3 (1.1 to 4.7) | ||
| Two to four | 40.1 (34.2 to 45.9) | 2.9 (0.9 to 5.0) | 5.0 (2.7 to 9.4) | 1.6 (0.7 to 3.6) | |
| Five or more | 42.3 (32.8 to 51.7) | 8.3 (3.1 to 13.5) | 13.5 (7.1 to 25.5) | 3.3 (1.4 to 7.8) | |
| Number of HIV-negative/status UK partners | |||||
| None | 20.9 (18.6 to 23.2) | 1.1 (0.5 to 1.7) | Reference | Reference | |
| One | 22.3 (18.2 to 26.4) | 1.0 (0.0 to 2.0) | 1.0 (0.5 to 2.0) | ||
| Two to four | 34.6 (28.6 to 40.5) | 2.5 (0.5 to 4.4) | 2.2 (1.2 to 4.3) | 1.2 (0.5 to 2.9) | |
| Five or more | 33.7 (27.6 to 39.9) | 4.8 (2.0 to 7.5) | 3.5 (1.9 to 6.2) | 1.2 (0.5 to 3.0) | |
| Anal sex | |||||
| No partner | 15.8 (13.3 to 18.4) | 1.0 (0.3 to 1.7) | Reference | Reference | |
| Sexually active but no anal sex§ | 20.8 (16.5 to 25.1) | 1.3 (0.0 to 2.5) | 1.9 (1.1 to 3.3) | 0.5 (0.1 to 3.0) | |
| Anal sex always with a condom | 25.6 (21.2 to 30.0) | 3.4 (1.5 to 5.3) | 1.9 (0.5 to 6.9) | 3.3 (1.0 to 11.4) | |
| Any condomless anal sex | 36.8 (32.9, 40.7) | 6.0 (4.1 to 8.0) | 7.0 (2.5 to 19.0) | 3.6 (1.0 to 12.3) | |
| Anal sex with HIV+ partner | |||||
| No HIV+ partner | 19.0 (16.9 to 21.2) | 0.8 (0.3 to 1.2) | Reference | Reference | |
| Sexually active with HIV+ partner but no anal sex§ | 17.1 (10.7 to 23.5) | 0.0 (0.0 to 0.0) | 1.0 (0.2 to 4.4) | 1.2 (0.3 to 5.2) | |
| Anal sex with HIV+ partner always with a condom | 28.5 (21.5 to 35.4) | 1.2 (0.0 to 2.8) | 4.0 (1.8 to 8.8) | 2.8 (0.6 to 13.4) | |
| Any condomless anal sex with HIV+ partner | 40.6 (35.9 to 45.2) | 5.4 (3.3 to 7.5) | 6.3 (3.7 to 10.8) | 2.2 (0.5 to 9.8) | |
| Anal sex with HIV−/UK partner | |||||
| No HIV−/UK partner | 20.9 (18.6 to 23.2) | 1.1 (0.5 to 1.7) | Reference | Reference | |
| Sexually active with HIV−/UK partner but no anal sex§ | 22.3 (16.9 to 27.7) | 0.4 (0.0 to 1.3) | 0.7 (0.2 to 2.0) | 1.6 (1.5 to 5.1) | |
| Anal sex with HIV−/UK partner always with a condom | 29.6 (25.0 to 34.2) | 2.8 (1.2 to 4.5) | 2.0 (1.1 to 3.7) | 2.2 (0.7 to 6.9) | |
| Any condomless anal sex with HIV−/UK partner | 35.0 (29.3 to 40.7) | 3.3 (1.2 to 5.5) | 3.0 (1.6 to 5.3) | 1.7 (0.6 to 5.3) | |
| Any recreational drug use in preceding 6 months¶ | |||||
| No | 21.1 (19.2 to 23.0) | 0.9 (0.4 to 1.3) | Reference | Reference | Reference |
| Yes | 38.2 (33.7 to 42.8) | 4.7 (2.8 to 6.7) | 5.0 (3.1 to 5.9) | 1.8 (1.1 to 3.2) | 2.2 (1.2 to 3.9) |
UK=status unknown.
*Behaviours were time-updated at each completion of a sexual behaviour questionnaire.
†Cumulative incidence proportions for testing and diagnosis were calculated using Kaplan–Meier methods.
‡Multivariable models adjusted for variables shown plus baseline age, region and time-updated viral load. Model A includes measures of sexual behaviours with HIV-negative, HIV-positive and HIV status unknown partners grouped together. Model B distinguishes sexual behaviour according to partners' HIV status.
§The category ‘sexually active, but no anal sex’ was assigned to men who reported one or more partners to the question ‘In the last 3 months how many male partners have you had sex with?’ but responded ‘Never’ to the statements ‘I had anal sex with him’ for any reported HIV-positive or HIV-negative/status unknown partner.
¶Drug use was time -updated at each completion of a face-to-face interview. All drugs were combined to avoid multicollinearity.
MSM, men who have sex with men.