Table 3

Risk factor analysis for incidence and clearance of oral infection by any HPV (A) and high-risk HPVs (B) in HIV-infected and HIV-uninfected MSM using interval time homogeneous Markov models

A) Any HPVIncidenceClearance
HIV-infected MSMUnivariate HR (95% CI)Multivariate aHR (95% CI)Univariate HR (95% CI)Multivariate aHR (95% CI)
Age, >46 versus ≤46 years*0.59 (0.19 to 1.81) 0.33 (0.14 to 0.80) 0.30 (0.12 to 0.74)
Education, postgraduate versus undergraduate0.55 (0.18 to 1.67)0.48 (0.20 to 1.16)
Pack-years†
 011
 0.25–181.13 (0.33 to 3.87)0.38 (0.14 to 1.07)
 >182.20 (0.76 to 6.35)0.84 (0.32 to 2.18)
Number of lifetime partners for any sex‡
 <5011
 50–1504.14 (0.80 to 21.44)0.76 (0.19 to 2.98)
 >150 8.84 (1.95 to 40.16)0.65 (0.18 to 2.39)
Occasional partners for any sex, yes versus no1.38 (0.45 to 4.22)1.58 (0.55 to 4.58)
Number of lifetime partners for oral sex
 <2511
 25–951.49 (0.25 to 8.95)1.58 (0.26 to 9.55)1.24 (0.28 to 5.45)
 >95 7.65 (1.71 to 34.14) 8.46 (1.89 to 37.92)0.80 (0.21 to 3.07)
Number of recent partners for oral sex
 <311
 3–62.17 (0.70 to 6.82)0.81 (0.27 to 2.45)
 >60.99 (0.25 to 3.98)1.27 (0.47 to 3.41)
Condomless oral sex, yes versus no4.27 (0.58 to 31.53)n.e.
Oral health/hygiene, poor versus good0.72 (0.26 to 1.95)0.49 (0.22 to 1.14)
Oral care/condition, poor versus good0.81 (0.29 to 2.29)1.46 (0.60 to 3.54)
STI history
 No11
 Anogenital warts1.86 (0.60 to 5.77)0.28 (0.04 to 2.00)
 Other STIs1.87 (0.61 to 5.75)0.71 (0.29 to 1.75)
Nadir CD4+ T count, <200 versus ≥200 cells/mm3 0.59 (0.22 to 1.61)0.52 (0.22 to 1.22)
Current CD4+ T count, <500 versus ≥500 cells/mm3 0.85 (0.30 to 2.44)0.99 (0.39 to 2.50)
HIV-uninfected MSM
Age, >46 versus ≤46 years* 3.77 (1.36 to 10.45) 3.70 (1.30 to 10.52)1.07 (0.47 to 2.45)
Education, postgraduate versus undergraduate 0.28 (0.09 to 0.88)0.31 (0.09 to 1.00)1.21 (0.53 to 2.74)
Pack-years†
 011
 0.25–18 0.21 (0.04 to 0.95) 0.21 (0.05 to 0.93)1.13 (0.45 to 2.85)
 >181.02 (0.22 to 4.58)0.50 (0.10 to 2.41)0.74 (0.17 to 3.26)
Number of lifetime partners for any sex
 <5011
 50–1500.93 (0.27 to 3.24)1.09 (0.43 to 2.79)
 >1501.42 (0.43 to 4.71)0.75 (0.23 to 2.46)
Occasional partners for any sex, yes versus no1.86 (0.24 to 14.23)0.31 (0.09 to 1.10)
Number of lifetime partners for oral sex
 <2511
 25–950.49 (0.12 to 1.98)0.48 (0.18 to 1.27)
 >951.46 (0.48 to 4.39)0.63 (0.22 to 1.78)
Number of recent partners for oral sex
 <311
 3–63.98 (0.50 to 31.62)0.90 (0.30 to 2.72)0.93 (0.31 to 2.72)
 >63.54 (0.42 to 29.67) 0.18 (0.05 to 0.71) 0.18 (0.05 to 0.65)
Oral health/hygiene, poor versus good 2.88 (1.04 to 7.99)2.52 (0.88 to 7.27)1.36 (0.59 to 3.14)
Oral care/condition, poor versus good1.06 (0.34 to 3.34)0.52 (0.09 to 3.09)
STI history
 No11
 Anogenital warts0.83 (0.17 to 3.93)1.29 (0.47 to 3.52)
 Other STIs2.40 (0.82 to 7.02)0.93 (0.28 to 3.14)
B) High-risk HPVIncidenceClearance
HIV-infected MSMUnivariate
HR (95% CI)
Multivariate aHR (95% CI)Univariate
HR (95% CI)
Multivariate aHR (95% CI)
Age, >46 versus ≤46 years*1.64 (0.47 to 5.71)
Age (years)
 <36 11
 36–46 n.e.0.12 (0.01 to 1.09) 0.09 (0.01 to 0.79)
 >46 n.e. 0.09 (0.01 to 0.81) 0.04 (0.01 to 0.38)
Education, postgraduate versus undergraduate0.39 (0.08 to 1.87)0.59 (0.17 to 2.10)
Pack-years†
 011
 0.25–180.48 (0.05 to 4.68)0.60 (0.12 to 3.10)
 >183.31 (0.78 to 14.01)1.37 (0.38 to 4.99)
Number of lifetime partners for any sex
 <5011
 50–1503.79 (0.39 to 36.70)1.46 (0.17 to 12.18)
 >1507.16 (0.86 to 59.70)1.45 (0.23 to 9.05)
Occasional partners for any sex, yes versus no1.52 (0.32 to 7.21)1.41 (0.40 to 5.03)
Number of lifetime partners for oral sex
 <2511
 25–951.80 (0.16 to 20.03)2.65 (0.27 to 26.32)
 >955.80 (0.71 to 47.40)1.67 (0.25 to 11.10)
Number of recent partners for oral sex
 <311
 3–61.15 (0.27 to 4.86)0.80 (0.22 to 2.93)
 >60.69 (0.13 to 3.54)1.37 (0.25 to 7.61)
Condomless oral sex, yes versus no 11.85 (2.38 to 58.96) 13.40 (2.55 to 70.53)n.e.
Oral health/hygiene, poor versus good0.36 (0.07 to 1.79)1.04 (0.33 to 3.24)
Oral care/condition, poor versus good1.13 (0.29 to 4.41)0.57 (0.17 to 1.85)
STI history
 No11
 Anogenital warts0.50 (0.06 to 4.15)0.70 (0.09 to 5.36)
 Other STIs1.21 (0.30 to 4.88)1.72 (0.52 to 5.67)
Nadir CD4+ T count, <200 versus ≥200 cells/mm3 1.30 (0.27 to 6.25) 0.22 (0.05 to 0.99) 0.14 (0.03 to 0.75)
Current CD4+ T count, <500 versus ≥500 cells/mm3 1.47 (0.31 to 7.14)0.39 (0.11 to 1.41)
HIV-uninfected MSM
Age, >46 versus ≤46 years* 6.31 (1.27 to 31.38) 5.33 (1.06 to 26.68)1.12 (0.37 to 3.44)
Education, postgraduate versus undergraduate0.52 (0.12 to 2.17)1.66 (0.53 to 5.15)
Pack-years†
 011
 0.25–180.91 (0.20 to 4.11)3.30 (0.98 to 11.05)
 >181.23 (0.14 to 11.13)6.61 (0.69 to 63.00)
Number of lifetime partners for any sex
 <5011
 50–1500.30 (0.03 to 2.94)0.68 (0.20 to 2.33)
 >1501.62 (0.36 to 7.29)0.43 (0.09 to 2.18)
Occasional partners for any sex, yes versus non.e.0.30 (0.06 to 1.42)
Number of lifetime partners for oral sex
 <2511
 25–950.30 (0.03 to 2.93)0.59 (0.16 to 2.15)
 >951.62 (0.36 to 7.27)0.60 (0.14 to 2.60)
Number of recent partners for oral sex
 <311
 3–64.26 (0.50 to 36.64)0.90 (0.22 to 3.64)
 >61.60 (0.14 to 17.75)0.33 (0.08 to 1.42)
Oral health/hygiene, poor versus good 5.21 (1.05 to 25.93)4.45 (0.89 to 22.30)1.47 (0.47 to 4.58)
Oral care/condition, poor versus good1.17 (0.23 to 5.85)0.44 (0.06 to 3.17)
STI history
 No11
 Anogenital warts1.45 (0.28 to 7.52)0.58 (0.13 to 2.68)
 Other STIs0.62 (0.07 to 5.37)1.97 (0.45 to 8.70)
  • Only the variables that resulted significantly associated with incidence and/or clearance from the univariate analysis (p<0.20) were included in the multivariable model (see Methods section for further details)

  • Condom use in oral sex was excluded from the analysis for HIV-uninfected MSM because the model did not converge.

  • Data in bold highlight statistically significant associations.

  • *Age, which was originally categorised into tertiles (<36, 36–46 and >46 years), was recoded as a binary variable (≤46 and >46 years) when the number of transitions for the category 36–46 years was too low to produce reliable estimates.

  • †Smoking, which was originally categorised into tertiles among smokers (0.25–5.50, 5.50–18 and >18 pack-years), was recoded into two categories (0.25–18.0 and >18 pack-years) since the number of transitions for the category 0.25–5.50 was too low to produce reliable estimates.

  • ‡Excluded from the multivariate analysis because of collinearity with number of lifetime partners for oral sex.

  • aHR, adjusted HR; HPV, human papillomavirus; MSM, men who have sex with men; n.e., not estimable; STI, sexually transmitted infection.