Univariate and multivariate analyses for behavioural risk factors of shigellosis among 79 MSM living with HIV in Taiwan, 2015–2016
| Variables | Cases (n=20) | Controls (n=59) | Crude OR (95% CI) | P value | Adjusted OR (95% CI) | P value |
| Age (years), median (range) | 30 (21–47) | 31 (21–50) | – | – | ||
| Age at HIV diagnosis (years), median (range) | 25 (20–46) | 28 (20–49) | – | – | ||
| Year of HIV diagnosis, n (%) | 0.6 (0.2 to 1.9) | 0.16 | ||||
| 2001–2010 | 7 (35) | 15 (25) | ||||
| 2011–2015 | 13 (65) | 44 (75) | ||||
| MSM, n (%) | 20 (100) | 59 (100) | ||||
| Region of residence, n (%) | 0.87 | |||||
| Northern | 19 (95) | 53 (90) | 1.0 | |||
| Central | 1 (5) | 5 (8) | 0.6 (0.1 to 5.1) | |||
| Southern | 0 (0) | 1 (2) | – | |||
| Marital status, n (%) | 1.8 (0.4 to 9.2) | 0.23 | ||||
| Single | 20 (100) | 58 (98) | ||||
| Married | 0 (0) | 1 (2) | ||||
| Education, n (%) | 0.5 (0.2 to 7.7) | 0.14 | ||||
| High school or below | 6 (30) | 10 (17) | ||||
| College or above | 14 (70) | 49 (83) | ||||
| Number of sex partners*, n (%) | 0.03 | |||||
| 0 | 1 (5) | 19 (32) | 1.0 | |||
| 1–5 | 9 (45) | 27 (47) | 1.8 (1.1 to 2.8) | 0.09 | ||
| ≥6 | 10 (50) | 13 (21) | 2.6 (1.1 to 5.9) | 0.02 | ||
| Venues of seeking casual sex partners*, n (%) | ||||||
| Online | 19 (95) | 25 (42) | 25.8 (3.2 to 206.0) | <0.01 | ||
| Sauna/gym | 3 (15) | 5 (8) | 1.9 (0.4 to 8.8) | 0.21 | ||
| Gay bar/private sex party | 5 (25) | 14 (23) | 1.1 (0.3 to 3.5) | 0.23 | ||
| Recreational drug used*†, n (%) | ||||||
| Poppers | 14 (70) | 11 (19) | 10.2 (3.2 to 32.5) | <0.01 | 10.9 (1.9 to 64.2) | <0.01 |
| Crystal methamphetamine | 12 (60) | 9 (15) | 8.3 (2.7 to 26.1) | <0.01 | ||
| Sildenafil/tadalafil | 12 (60) | 13 (22) | 5.3 (1.8 to 15.7) | 0.01 | ||
| GHB/GBL | 5 (25) | 5 (8) | 3.6 (0.9 to 14.1) | 0.05 | ||
| Ecstasy | 5 (25) | 5 (8) | 3.6 (0.9 to 14.1) | 0.05 | ||
| Marijuana | 5 (25) | 2 (3) | 9.5 (1.7 to 53.9) | <0.01 | ||
| 5-MeO-DIPT | 3 (15) | 2 (3) | 5.0 (0.8 to 32.6) | 0.08 | ||
| Ketamine | 2 (10) | 4 (7) | 1.6 (0.3 to 9.0) | 0.31 | ||
| Nitrous oxide | 2 (10) | 2 (3) | 3.2 (0.4 to 24.1) | 0.21 | ||
| Sexual activities*†, n (%) | ||||||
| Anal sex | 19 (95) | 40 (67) | 9.0 (1.1 to 72.5) | 0.03 | ||
| Oral sex | 19 (95) | 40 (66) | 9.0 (1.1 to 72.5) | 0.03 | ||
| Oral-to-anal sex | 17 (85) | 11 (19) | 24.7 (3.3 to 32.2) | <0.01 | 15.5 (3.6 to 66.7) | <0.01 |
| Chemsex | 13 (62) | 8 (13) | 11.8 (3.6 to 38.6) | <0.01 | 5.6 (1.4 to 22.7) | 0.01 |
P values are based on logistic regression for unmatched analysis because of the highly variable participation rate among originally matched pairs.
*Within 12 months before the diagnosis of shigellosis for cases, and within 12 months before the interview for controls.
†Chemsex was generally defined as intentional sex under the influence of three psychoactive drugs (crystal methamphetamine, GHB/GBL or mephedrone) immediately preceding and/or during the sexual session.8 However, because anecdotal data indicated mephedrone was rarely used among MSM living with HIV in Taiwan, mephedrone use was not included in the telephone interview. Therefore, chemsex in this study refers to use of crystal methamphetamine or GHB/GBL immediately proceeding and/or during the sexual session.
5-MeO-DIPT, 5-methoxy-diisopropyltryptamine; GBL, γ-butyrolactone; GHB, γ-hydroxybutyrate; MSM, men who have sex with men.