Table 2. Factors associated with prevalent anal HPV 16 infection.
| Independent variables | Prevalent Anal HPV 16 in category | Unadjusted analysis | Adjusted model | ||
|---|---|---|---|---|---|
| n (%) | OR | 95%CI | OR | 95%CI | |
| Age at baseline in years | 1.0 | 1.0–1.1 | 1.0 | 0.9–1.1 | |
| 19–39 | 6 (15.4%) | ||||
| 40–49 | 10 (15.4%) | ||||
| 50–69 | 7 (15.2%) | ||||
| Smoking | |||||
| Never | 10 (9.8%) | Ref. | Ref. | ||
| Past | 4 (18.2%) | 2.0 | 0.6–7.2 | 1.9 | 0.4–10.4 |
| Current | 9 (34.6%) | 4.9 | 1.7–13.8 | 6.0 | 1.5–23.9 |
| CD4 cell count at baseline (chart review) | |||||
| >200 (cells/μL of blood) | 19 (13.5%) | Ref. | Ref. | ||
| ≤200 (cells/μL of blood) | 4 (44.4%) | 5.1 | 1.3–20.8 | 0.9 | 0.1–6.4 |
| Nadir CD4 cell count (chart review) | |||||
| >200 (cells/μL of blood) | 5 (6.1%) | Ref. | Ref. | ||
| ≤200 (cells/μL of blood) | 18 (26.5%) | 5.5 | 1.9–15.9 | 8.4 | 2.0–34.3 |
| HIV viral load at baseline (chart review) | |||||
| < 40 copies/mL (undetectable) | 15 (12.9%) | Ref. | Ref. | ||
| ≥ 40 copies/mL (detectable) | 8 (23.5%) | 2.1 | 0.8–5.4 | 2.1 | 0.6–7.7 |
| Prevalent Cervical HPV 16 | |||||
| No | 19 (13.2%) | Ref. | Ref. | ||
| Yes | 4 (80.0%) | 26.3 | 2.8–248.1 | 14.7 | 1.0–222.5 |
| Anogenital herpes in past 6 months (self-report) | |||||
| No or don’t know | 18 (13.0%) | Ref. | Ref. | ||
| Yes | 5 (45.5%) | 5.6 | 1.5–20.3 | 9.8 | 1.7–56.8 |
| Lifetime number of anal sex partners | |||||
| 0 or 1 | 16 (12.0%) | Ref. | Ref. | ||
| 2 or more | 7 (41.2%) | 5.1 | 1.7–15.3 | 3.0 | 0.7–12.2 |
Note. HPV, human papillomavirus; CI, confidence interval; OR, odds ratio; Ref., reference category. The dependent variable, anal HPV 16 infection, was coded as 0 = "No HPV type 16 DNA detected in anal canal" and 1 = "HPV type 16 DNA detected in anal canal". The following variables were included in the adjusted model: age as a numerical continuous variable, smoking status, CD4 count at baseline, nadir CD4 count, HIV viral load at baseline, prevalent cervical HPV-16, self-reported history of anogenital herpes in the past 6 months, total of 2 or more partners for recent or remote anal sex.