Table 3

Associations of polydrug use and drug use associated with chemsex, with measures of HIV-related behaviours, among 949 MSM in the AURAH2 study who reported anal or vaginal sex in the past 3 months

HIV-related behaviour outcome	Poly drug use (past 3 months)			Chemsex drug use (past 3 months)
HIV-related behaviour outcome	Unadjusted PR (95% CI) P value*	Adjusted (i) PR (95% CI) P value*	Adjusted (ii) PR (95% CI) P value*	Unadjusted PR (95% CI) P value*	Adjusted (i) PR (95% CI) P value*	Adjusted (ii) PR (95% CI) P value*
CLS with one or more partners (past 3 months)	1.30 (1.20 to 1.40)	1.31 (1.21 to 1.42)	1.31 (1.21 to 1.41)	1.32 (1.23 to 1.43)	1.33 (1.23 to 1.44)	1.33 (1.23 to 1.44)
CLS with one or more partners (past 3 months)	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
CLS with two or more partners (past 3 months)	1.91 (1.64 to 2.24)	1.93 (1.65 to 2.25)	1.91 (1.63 to 2.23)	1.95 (1.67 to 2.28)	1.95 (1.67 to 2.28)	1.94 (1.66 to 2.27)
CLS with two or more partners (past 3 months)	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
CLS with unknown/HIV-positive partner (past 3 months)	1.71 (1.44 to 2.03)	1.69 (1.43 to 2.02)	1.71 (1.43 to 2.03)	1.83 (1.54 to 2.17)	1.81 (1.52 to 2.16)	1.82 (1.53 to 2.16)
CLS with unknown/HIV-positive partner (past 3 months)	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
Receptive CLS with unknown status partner (past 3 months)	1.37 (0.98 to 1.89)	1.34 (0.97 to 1.87)	1.34 (0.97 to 1.85)	1.36 (0.98 to 1.89)	1.34 (0.97 to 1.86)	1.34 (0.97 to 1.85)
Receptive CLS with unknown status partner (past 3 months)	0.062	0.07	0.08	0.07	0.08	0.08
Bacterial STI diagnosis (past year)	1.65 (1.43 to 1.91)	1.66 (1.44 to 1.91)	1.66 (1.43 to 1.91)	1.69 (1.43 to 1.91)	1.66 (1.43 to 1.91)	1.65 (1.43 to 1.91)
Bacterial STI diagnosis (past year)	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
Eleven or more new sexual partners (past year)	1.64 (1.43 to 1.89)	1.62 (1.41 to 1.86)	1.61 (1.39 to 1.85)	1.61 (1.39 to 1.85)	1.56 (1.36 to 1.79)	1.55 (1.35 to 1.78)
Eleven or more new sexual partners (past year)	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
Group sex (past 3 months)	2.41 (2.11 to 2.75)	2.38 (2.08 to 2.72)	2.38 (2.09 to 2.73)	2.39 (2.09 to 2.75)	2.39 (2.09 to 2.74)	2.39 (2.09 to 2.74)
Group sex (past 3 months)	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
PEP use (past year)	2.16 (1.72 to 2.71)	2.15 (1.71 to 2.71)	2.16 (1.72 to 2.72)	2.47 (1.95 to 3.11)	2.43 (1.93 to 3.08)	2.44 (1.93 to 3.08)
PEP use (past year)	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
PrEP use (past year)	2.46 (1.49 to 4.01)	2.54 (1.54 to 4.19)	2.69 (1.64 to 4.43)	2.13 (1.29 to 3.52)	2.28 (1.39 to 3.71)	2.38 (1.46 to 3.86)
PrEP use (past year)	<0.001	<0.001	<0.001	0.003	0.001	<0.001
Recent HIV test (within past 6 months)	1.16 (1.08 to 1.25)	1.16 (1.08 to 1.25)	1.17 (1.09 to 1.26)	1.18 (1.10 to 1.26)	1.18 (1.10 to 1.27)	1.18 (1.11 to 1.27)
Recent HIV test (within past 6 months)	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001

Adjusted model (i) age (continuous variable), ethnicity, sexual identity, university education, ongoing relationship status.
Adjusted model (ii) age (continuous variable), ethnicity, sexual identity, university education, ongoing relationship status, higher-risk drinking, depressive symptoms (PHQ-9 ≥10) (missing values included in variables for adjusted models).
*P values by Wald test.
AURAH2, Attitudes to and Understanding Risk of Acquisition of HIV over Time; CLS, condomless sex; MSM, men who have sex with men; PEP, post-exposure prophylaxis; PrEP, pre-exposure prophylaxis.