Table 1 Factors associated with HIV-seroconversion in 1529 men who have sex with men attending the Antwerp Helpcenter (univariate and multivariate associations)

Age—Median, years (IQR)

37 (31–46)

34 (28–43)

1.0 (1.0–1.0)

1.0 (1.0–1.0)

World region

**

*

 West Europe

48 (65.8)

1185 (81.4)

Ref

Ref

 Sub Saharan Africa

3 (4.1)

47 (3.2)

1.6 (0.5–5.2)

2.0 (0.6–6.7)

 Rest

22 (30.1)

224 (15.4)

2.4 (1.4–4.1)

2.2 (1.2–3.8)

Education

*

 Secondary or less

38 (52.1)

529 (36.3)

Ref

Ref

 Tertiary

35 (48.0)

927 (63.7)

0.5 (0.3–0.8)

0.6 (0.4–1.0)

Partners in last 12 months (n)

**

 0–1

3 (4.1)

209 (14.4)

Ref

 2–4

17 (23.3)

604 (41.5)

2.0 (0.6–6.8)

NE

 ≥ 5

38 (52.1)

481(33.0)

5.5 (1.7–18.0)

NE

 Missing

15(20.6)

162 (11.1)

6.5 (1.8–22.7)

NE

Condom usage

*

 Always

14 (19.2)

316 (21.7)

Ref

 Sometimes

38 (52.1)

788 (54.1)

1.1 (0.6–2.0)

NE

 Never

3 (4.1)

151 (10.4)

0.4 (0.1–1.6)

NE

 Missing

18 (24.7)

201 (13.8)

2.0 (1.0–4.2)

NE

Unprotected sex under influence of: ^a

 Alcohol

**

  No

22 (30.1)

779 (53.5)

Ref

  Yes

27 (37.0)

474 (32.6)

2.0 (1.1–3.6)

NE

  Missing

24 (32.9)

203 (13.9)

4.2 (2.3–7.6)

NE

 Ecstasy/cocaine/amphetamines/GHB

**

**

  No

27 (37.0)

1111 (76.3)

Ref

Ref

  Yes

22 (30.1)

142 (9.8)

6.4 (3.5–11.5)

5.7 (3.2–10.4)

  Missing

24 (32.9)

203 (13.9)

4.9 (2.8–8.6)

2.9 (1.6–5.1)

 Marijuana

**

  No

43 (58.9)

1125 (77.3)

Ref

  Yes

6 (8.2)

128 (8.8)

1.2 (0.5–2.9)

NE

  Missing

24 (32.9)

203 (13.9)

3.1 (1.8–5.2)

NE

Use of drugs: ^b

 Alcohol

**

  No

7 (9.6)

315 (21.6)

Ref

  Yes

31 (42.5)

706 (48.5)

2.0 (0.9–4.5)

NE

  Missing

35 (48.0)

435 (29.9)

3.6 (1.6–8.3)

NE

 Ecstasy/cocaine/amphetamines/GHB

**

  No

19 (26.0)

885 (60.8)

Ref

  Yes

24 (32.9)

186 (12.8)

6.0 (3.2–11.2)

NE

  Missing

30 (41.1)

385 (26.4)

3.6 (2.0–6.5)

NE

 Marijuana

*

  No

24 (32.9)

712 (48.9)

Ref

  Yes

10 (13.7)

204 (14.0)

1.5 (0.7–3.1)

NE

  Missing

39 (53.4)

540 (37.1)

2.1 (1.3–3.6)

NE