Table 3 Factors associated with syphilis infection among 3717 Chinese MSM
Characteristic | No. of MSM syphilis positive (%) | Crude OR (95% CI) | P-value | AOR (95% CI) | P-value |
|---|---|---|---|---|---|
Commercial sex | |||||
 NC-MSM | 302 (8.7) | Ref. | 0.28 | Ref. | 0.262 |
 MSM-buying | 7 (6.8) | 0.8 (0.4–1.7) |  | 0.5 (0.2–1.4) |  |
 MSM-selling | 18 (12.1) | 1.4 (0.9–2.4) |  | 1.5 (0.7–3.3) |  |
HIV positive | |||||
 No | 249 (7.5) | Ref. | <0.001 | Ref. | <0.001 |
 Yes | 78 (19.0) | 2.9 (2.2–3.8) |  | 2.0 (1.5–2.8) |  |
HSV-2 positive | |||||
 No | 208 (7.0) | Ref. | <0.001 | Ref. | <0.001 |
 Yes | 81 (19.8) | 3.3 (2.5–4.4) |  | 2.7 (2.0–3.7) |  |
Age (per year) |  | 1.0 (1.0–1.1) | 0.001 | 1.0 (1.0–1.1) | 0.002 |
Married to a woman | |||||
 No | 222 (7.9) | Ref. | <0.001 | Ref. | 0.45 |
 Yes | 105 (11.8) | 1.6 (1.2–2.0) |  | 0.9 (0.6–1.2) |  |
Time living in the study city | |||||
 >6 months | 244 (8.7) | Ref. | 0.31 | _ | _ |
 ≤6 months | 18 (6.9) | 0.8 (0.5–1.3) |  |  |  |
Student | |||||
 No | 305 (9.6) | Ref. | <0.001 | Ref. | 0.170 |
 Yes | 22 (4) | 0.4 (0.3–0.6) |  | 0.7 (0.4–1.2) |  |
Education | |||||
 College or above | 145 (6.8) | Ref. | <0.001 | Ref. | 0.080 |
 High school or below | 182 (11.5) | 1.8 (1.4–2.2) |  | 1.3 (1.0–1.7) |  |
Seeking partners online | |||||
 No | 135 (11.7) | Ref. | <0.001 | Ref. | 0.082 |
 Yes | 190 (7.4) | 0.6 (0.5–0.8) |  | 0.8 (0.6–1.0) |  |
Number of male sex partners in past 6Â months | |||||
 0–2 | 175 (7.6) | Ref. | 0.002 | Ref. | 0.002 |
 3–9 | 113 (10.7) | 1.5 (1.1–1.9) |  | 1.5 (1.1–1.9) |  |
 ≥10 | 35 (11.9) | 1.7 (1.1–2.4) |  | 1.5 (1.0–2.5) |  |
Drug use in past 6Â months | |||||
 No | 182 (7.8) | Ref. | 0.024 | Ref. | 0.007 |
 Yes | 91 (10.3) | 1.4 (1.0–1.8) |  | 1.5 (1.1–2.0) |  |
UAI in past 6Â months | |||||
 No | 102 (7.3) | Ref. | 0.013 | Ref. | 0.038 |
 Yes | 225 (9.7) | 1.4 (1.1–1.7) |  | 1.3 (1.0–1.8) |  |
Predominant position in anal sex | |||||
 Receptive | 265 (12.8) | Ref. | 0.23 | _ | _ |
 Insertive | 139 (9.0) | 0.9 (0.7–1.1) |  |  |  |