Table 2 Bivariate analyses of factors predicting past year quasi-legal psychoactive substance use among HIV-positive males accessing HIV care in Japan (n = 895)

 Median (IQR)

39 (33–44)

43 (37–52)

 Per year older

0.95 (0.93–0.97)

<0.001

  < Secondary education

1 (0.9%)

21 (2.7%)

0.32 (0.07–1.53)

0.153

  ≥ Secondary education

114 (99.1%)

759 (97.3%)

ref

 Yes

61 (53.0%)

344 (44.1%)

1.43 (1.04–1.97)

0.028

 No

54 (47.0%)

436 (55.9%)

ref

  < 1 million Yen^a

28 (24.4%)

210 (26.9%)

0.76 (0.54–1.09)

0.444

 1–2.99 million Yen^a

29 (25.2%)

196 (25.1%)

0.85 (0.52–1.39)

0.995

 3–4.99 million Yen^a

28 (24.3%)

202 (25.9%)

0.80 (0.63–1.01)

0.518

  ≥ 5 million Yen^a

30 (26.1%)

171 (22.1%)

ref

 Currently on ART

106 (92.2%)

741 (95.0%)

0.62 (0.29–1.31)

0.210

 Never on ART

9 (7.8%)

39 (5.0%)

ref

 Yes

32 (27.8%)

236 (30.3%)

0.89 (0.55–1.43)

0.625

 No

83 (72.2%)

544 (69.7%)

ref

 Male-to-male sexual behaviour

111 (96.5%)

647 (82.9%)

5.70 (3.29–9.88)

<0.001

 Other

4 (3.5%)

133 (17.1%)

ref

 Yes

9 (7.8%)

46 (5.9%)

1.36 (0.67–2.72)

0.394

 No

106 (92.2%)

734 (94.1%)

ref

 Score of ≥ 13

13 (11.3%)

99 (12.7%)

0.88 (0.48–1.61)

0.672

 Score of < 13

102 (88.7%)

681 (87.3%)

ref

 Yes

65 (56.5%)

187 (24.0%)

4.12 (2.90–5.86)

<0.001

 No

50 (43.5%)

593 (76.0%)

ref

 Yes

25 (21.7%)

62 (8.0%)

3.22 (1.79–5.78)

<0.001

 No

90 (78.3%)

718 (92.0%)

ref

 Yes

41 (35.7%)

68 (8.7%)

5.80 (3.79–8.88)

<0.001

 No

74 (64.3%)

712 (91.3%)

ref

 Yes

19 (16.5%)

39 (5.0%)

3.76 (2.41–5.87)

<0.001

 No

96 (83.5%)

741 (95.0%)

ref

 Yes

8 (7.0%)

15 (1.9%)

3.81 (1.62–9.01)

0.002

 No

107 (93.0%)

765 (98.1%)

ref