Table 2

Adjusted/unadjusted odds of rectal infection among HIV-uninfected MSM on PrEP performing rectal douching and/or enema

Rectal infection
Total (n=384)Unadjusted ORAdjusted OR*
N (%)OR95% CIP valueaOR95% CIP value
Rectal douching/enema
 Never125 (33%)
 Less than weekly138 (36%)1.971.11 to 3.490.0201.750.96 to 3.200.070
 Weekly or more121 (31%)4.572.58 to 8.09<0.0013.591.90 to 6.78<0.001
Substance use
 No92 (24%)
 Yes292 (76%)2.831.59 to 5.03<0.0011.971.06 to 3.670.033
Number of male sexual partners† (med/IQR)6 (3–10)1.451.23 to 1.72<0.0011.331.10 to 1.600.003
Number cARS (med/IQR)4 (0–16)1.021.01 to 1.04<0.0011.010.99 to 1.020.093
Age (years) (mean/SD)35 (±9)0.960.93 to 0.980.0010.950.92 to 0.98<0.001
Antibiotic use
 No274 (71%)
 Yes110 (29%)1.090.68 to 1.730.7260.820.49 to 1.380.455
  • *Adjusted for age, number of condomless anal receptive sex, log2 median number of male sexual partners, use of antibiotics and substance use.

  • †Log2 transformed median number of partners in past 3 months.

  • cARS, condomless anal receptive sex; MSM, men who have sex with men; PrEP, pre-exposure prophylaxis; Substance use, methamphetamine/hallucinogen/dissociative/popper.