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 HPV | Incidence | Clearance | ||
| HIV-infected MSM | Univariate 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 undergraduate | 0.55 (0.18 to 1.67) | 0.48 (0.20 to 1.16) | ||
| Pack-years† | ||||
| 0 | 1 | 1 | ||
| 0.25–18 | 1.13 (0.33 to 3.87) | 0.38 (0.14 to 1.07) | ||
| >18 | 2.20 (0.76 to 6.35) | 0.84 (0.32 to 2.18) | ||
| Number of lifetime partners for any sex‡ | ||||
| <50 | 1 | 1 | ||
| 50–150 | 4.14 (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 no | 1.38 (0.45 to 4.22) | 1.58 (0.55 to 4.58) | ||
| Number of lifetime partners for oral sex | ||||
| <25 | 1 | 1 | ||
| 25–95 | 1.49 (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 | ||||
| <3 | 1 | 1 | ||
| 3–6 | 2.17 (0.70 to 6.82) | 0.81 (0.27 to 2.45) | ||
| >6 | 0.99 (0.25 to 3.98) | 1.27 (0.47 to 3.41) | ||
| Condomless oral sex, yes versus no | 4.27 (0.58 to 31.53) | n.e. | ||
| Oral health/hygiene, poor versus good | 0.72 (0.26 to 1.95) | 0.49 (0.22 to 1.14) | ||
| Oral care/condition, poor versus good | 0.81 (0.29 to 2.29) | 1.46 (0.60 to 3.54) | ||
| STI history | ||||
| No | 1 | 1 | ||
| Anogenital warts | 1.86 (0.60 to 5.77) | 0.28 (0.04 to 2.00) | ||
| Other STIs | 1.87 (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† | ||||
| 0 | 1 | 1 | ||
| 0.25–18 | 0.21 (0.04 to 0.95) | 0.21 (0.05 to 0.93) | 1.13 (0.45 to 2.85) | |
| >18 | 1.02 (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 | ||||
| <50 | 1 | 1 | ||
| 50–150 | 0.93 (0.27 to 3.24) | 1.09 (0.43 to 2.79) | ||
| >150 | 1.42 (0.43 to 4.71) | 0.75 (0.23 to 2.46) | ||
| Occasional partners for any sex, yes versus no | 1.86 (0.24 to 14.23) | 0.31 (0.09 to 1.10) | ||
| Number of lifetime partners for oral sex | ||||
| <25 | 1 | 1 | ||
| 25–95 | 0.49 (0.12 to 1.98) | 0.48 (0.18 to 1.27) | ||
| >95 | 1.46 (0.48 to 4.39) | 0.63 (0.22 to 1.78) | ||
| Number of recent partners for oral sex | ||||
| <3 | 1 | 1 | ||
| 3–6 | 3.98 (0.50 to 31.62) | 0.90 (0.30 to 2.72) | 0.93 (0.31 to 2.72) | |
| >6 | 3.54 (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 good | 1.06 (0.34 to 3.34) | 0.52 (0.09 to 3.09) | ||
| STI history | ||||
| No | 1 | 1 | ||
| Anogenital warts | 0.83 (0.17 to 3.93) | 1.29 (0.47 to 3.52) | ||
| Other STIs | 2.40 (0.82 to 7.02) | 0.93 (0.28 to 3.14) |
| B) High-risk HPV | Incidence | Clearance | ||
| HIV-infected MSM | Univariate 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 | 1 | 1 | ||
| 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 undergraduate | 0.39 (0.08 to 1.87) | 0.59 (0.17 to 2.10) | ||
| Pack-years† | ||||
| 0 | 1 | 1 | ||
| 0.25–18 | 0.48 (0.05 to 4.68) | 0.60 (0.12 to 3.10) | ||
| >18 | 3.31 (0.78 to 14.01) | 1.37 (0.38 to 4.99) | ||
| Number of lifetime partners for any sex | ||||
| <50 | 1 | 1 | ||
| 50–150 | 3.79 (0.39 to 36.70) | 1.46 (0.17 to 12.18) | ||
| >150 | 7.16 (0.86 to 59.70) | 1.45 (0.23 to 9.05) | ||
| Occasional partners for any sex, yes versus no | 1.52 (0.32 to 7.21) | 1.41 (0.40 to 5.03) | ||
| Number of lifetime partners for oral sex | ||||
| <25 | 1 | 1 | ||
| 25–95 | 1.80 (0.16 to 20.03) | 2.65 (0.27 to 26.32) | ||
| >95 | 5.80 (0.71 to 47.40) | 1.67 (0.25 to 11.10) | ||
| Number of recent partners for oral sex | ||||
| <3 | 1 | 1 | ||
| 3–6 | 1.15 (0.27 to 4.86) | 0.80 (0.22 to 2.93) | ||
| >6 | 0.69 (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 good | 0.36 (0.07 to 1.79) | 1.04 (0.33 to 3.24) | ||
| Oral care/condition, poor versus good | 1.13 (0.29 to 4.41) | 0.57 (0.17 to 1.85) | ||
| STI history | ||||
| No | 1 | 1 | ||
| Anogenital warts | 0.50 (0.06 to 4.15) | 0.70 (0.09 to 5.36) | ||
| Other STIs | 1.21 (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 undergraduate | 0.52 (0.12 to 2.17) | 1.66 (0.53 to 5.15) | ||
| Pack-years† | ||||
| 0 | 1 | 1 | ||
| 0.25–18 | 0.91 (0.20 to 4.11) | 3.30 (0.98 to 11.05) | ||
| >18 | 1.23 (0.14 to 11.13) | 6.61 (0.69 to 63.00) | ||
| Number of lifetime partners for any sex | ||||
| <50 | 1 | 1 | ||
| 50–150 | 0.30 (0.03 to 2.94) | 0.68 (0.20 to 2.33) | ||
| >150 | 1.62 (0.36 to 7.29) | 0.43 (0.09 to 2.18) | ||
| Occasional partners for any sex, yes versus no | n.e. | 0.30 (0.06 to 1.42) | ||
| Number of lifetime partners for oral sex | ||||
| <25 | 1 | 1 | ||
| 25–95 | 0.30 (0.03 to 2.93) | 0.59 (0.16 to 2.15) | ||
| >95 | 1.62 (0.36 to 7.27) | 0.60 (0.14 to 2.60) | ||
| Number of recent partners for oral sex | ||||
| <3 | 1 | 1 | ||
| 3–6 | 4.26 (0.50 to 36.64) | 0.90 (0.22 to 3.64) | ||
| >6 | 1.60 (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 good | 1.17 (0.23 to 5.85) | 0.44 (0.06 to 3.17) | ||
| STI history | ||||
| No | 1 | 1 | ||
| Anogenital warts | 1.45 (0.28 to 7.52) | 0.58 (0.13 to 2.68) | ||
| Other STIs | 0.62 (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.