Results from multinomial logistic regression analysis of sexually active patients in the past 2 months whose viral loads were >1500 copies/mL during that time, 2014–2015 (n=487)
| Odds of condomless anal/vaginal intercourse with HIV-positive partners only (serosorting) versus Always used a condom during anal/vaginal intercourse | Odds of condomless anal/vaginal intercourse with at-risk partners versus Always used a condom during anal/vaginal intercourse | |||
| Unadjusted OR (95% CI) | Adjusted‡ OR (95% CI) | Unadjusted OR (95% CI) | Adjusted‡ OR (95% CI) | |
| Gender/sexual orientation§ | ||||
| Heterosexual men | Ref | Ref | Ref | Ref |
| MSM | 3.38 (2.03 to 5.64)** | 3.03 (1.73 to 5.31)** | 3.88 (1.84 to 8.18)** | 3.36 (1.52 to 7.46)** |
| Women | 0.91 (0.51 to 1.62) | 0.87 (0.48 to 1.57) | 1.97 (0.91 to 4.25) | 1.90 (0.85 to 4.22) |
| Age at time of study entry, years | ||||
| 18–35 | Ref | Ref | Ref | Ref |
| 36–50 | 0.87 (0.56 to 1.36) | 1.10 (0.68 to 1.80) | 0.65 (0.36 to 1.16) | 0.83 (0.44 to 1.56) |
| Over 50 | 0.43 (0.23 to 0.80)** | 0.62 (0.31 to 1.22) | 0.42 (0.19 to 0.94)* | 0.56 (0.23 to 1.33) |
| Race/ethnicity | ||||
| White, non-Hispanic | Ref | Ref | Ref | Ref |
| Black, non-Hispanic | 0.54 (0.31 to 0.92)* | 0.74 (0.41 to 1.33) | 0.59 (0.30 to 1.19) | 0.73 (0.34 to 1.55) |
| Hispanic | 0.72 (0.37 to 1.41) | 0.86 (0.39 to 1.88) | 0.89 (0.38 to 2.09) | 0.99 (0.38 to 2.61) |
| Other | 0.78 (0.23 to 2.62) | 0.68 (0.19 to 2.50) | 0.71 (0.14 to 3.77) | 0.62 (0.11 to 3.44) |
| Injection drug use as HIV acquisition risk factor¶ | ||||
| No | Ref | Ref | Ref | Ref |
| Yes | 1.28 (0.66 to 2.48) | 1.26 (0.60 to 2.63) | 2.16 (1.02 to 4.56)* | 2.49 (1.09 to 5.67)* |
| Recency of testing HIV positive (from time of study entry) | ||||
| 3–12 months | Ref | Ref | Ref | Ref |
| 13+ months | 0.49 (0.22 to 1.08) | 0.50 (0.22 to 1.17) | 0.37 (0.15 to 0.93)* | 0.45 (0.16 to 1.22) |
| Language of CASI | ||||
| English | Ref | Ref | Ref | Ref |
| Spanish | 0.50 (0.18 to 1.36) | 0.34 (0.10 to 1.14) | 0.63 (0.18 to 2.18) | 0.50 (0.11 to 2.16) |
| Viral load (copies/mL) contemporaneous to sexual behaviour | ||||
| >1500–10 000 | Ref | Ref | Ref | Ref |
| 10 001–50 000 | 1.49 (0.91 to 2.43) | 1.17 (0.69 to 1.99) | 0.98 (0.52 to 1.86) | 0.86 (0.43 to 1.69) |
| 50 001 and higher | 1.16 (0.70 to 1.92) | 0.96 (0.56 to 1.66) | 0.94 (0.49 to 1.78) | 0.80 (0.40 to 1.57) |
| Currently taking ART | ||||
| No | Ref | Ref | Ref | Ref |
| Yes | 0.53 (0.35 to 0.81)** | 0.64 (0.41 to 1.01) | 0.49 (0.29 to 0.84)** | 0.62 (0.35 to 1.10) |
*p<0.05.
**p<0.01.
†At-risk partners were those perceived by study participant to be HIV-negative or of unknown serostatus at the time of the sexual activity.
‡The multivariable model adjusts for all variables in the first column.
§There were five transgender participants. They were omitted as a separate subgroup of the gender/sexual orientation variable, but were retained in the other variables for the unadjusted analyses.
¶This does not reflect whether the patient is a current injection drug user.
CASI, computer-assisted self-interview; MSM, men who have sex with other men.