Characteristics and trends in injecting risk behaviour of 2966 current injecting drug users recruited during a series of cross sectional surveys in Glasgow 1990–1999
| 1990 (n=503) | 1991 (n=535) | 1992 (n=515) | 1993 (n=505) | 1994 (n=518) | 1999 (n=390) | |
| Demographic characteristics | ||||||
| Age (y) (9 non-responses) | ||||||
| mean/median (SD) | 24.4/23.5 (4.6) | 25.6/25.1 (4.6) | 26.1/25.2 (4.4) | 26.5/25.9 (4.7) | 27.8/27.2 (5.0) | 26.1/25.4 (4.7) |
| Men | ||||||
| % (n/N) | 71% (356/503) | 76% (407/535) | 75% (385/515) | 70% (354/505) | 69% (355/518) | 63% (247/390) |
| Time since onset of injecting (19 non-responses) | ||||||
| mean/median (SD) | 6.4/6.0 (3.6) | 7.2/6.9 (3.9) | 7.7/7.9 (4.2) | 7.9/7.9 (4.6) | 8.7/8.8 (4.8) | 3.8/3.31-153 (2.8) |
| Frequency of injecting drugs in previous six months (13 non-responses) | ||||||
| <2 times daily | 23% (113/499) | 22% (114/530) | 17% (86/515) | 23% (115/504) | 29% (150/515) | 29% (113/390) |
| 2–3 times daily | 43% (215/499) | 45% (240/530) | 37% (193/515) | 42% (210/504) | 43% (219/515) | 41% (158/390) |
| >3 times daily | 34% (171/499) | 33% (176/530) | 46% (236/515) | 35% (179/504) | 28% (146/515) | 30% (119/390) |
| Injecting risk behaviour in the previous six months 1-151 | ||||||
| (a) Injected with used needle/syringe at least once | ||||||
| Prevalence of risk factor (10 non-responses) | 43% (215/502) | 29% (155/532) | 27% (138/512) | 33% (164/504) | 32% (166/517) | 36% (141/389) |
| Adjusted OR (95% CI) | 1.92 (1.47, 2.53)1-150 | 1.09 (0.83, 1.44) | 1.00 (baseline) | 1.39 (1.05, 1.83)1-150 | 1.54 (1.16, 2.04)1-150 | 1.60 (1.17, 2.21)1-150 |
| (b) Injected with used needle/syringe at least weekly | ||||||
| Prevalence of risk factor (10 non-responses) | 17% (84/502) | 9% (47/532) | 6% (30/512) | 8% (42/504) | 8% (40/517) | 12% (46/389) |
| Adjusted OR (95% CI) | 2.90 (1.86, 4.53)1-150 | 1.54 (0.95, 2.50) | 1.00 (baseline) | 1.51 (0.93, 2.46) | 1.55 (0.94, 2.56) | 2.36 (1.38, 4.02)1-150 |
| (c) Injected with used needle/syringe from more than one person | ||||||
| Prevalence of risk factor (22 non-responses) | 25% (126/498) | 14% (76/530) | 12% (59/511) | 15% (74/502) | 16% (80/517) | 19% (74/386) |
| Adjusted OR (95% CI) | 2.50 (1.77, 3.54)1-150 | 1.27 (0.88, 1.85) | 1.00 (baseline) | 1.43 (0.99, 2.08) | 1.77 (1.22, 2.57)1-150 | 1.76 (1.16, 2.66)1-150 |
| (d) Injected with used needle/syringe from a casual acquaintance1-152 | ||||||
| Prevalence of risk factor (14 non-responses) | 12% (62/501) | 7% (39/529) | 4% (22/512) | 8% (39/504) | 9% (44/517) | 10% (39/389) |
| Adjusted OR (95% CI) | 3.36 (2.01, 5.62)1-150 | 1.77 (1.03, 3.07)1-150 | 1.00 (baseline) | 1.99 (1.16, 3.43)1-150 | 2.44 (1.43, 4.19)1-150 | 4.04 (2.21, 7.38)1-150 |
↵1-151 Odds ratios were adjusted for other factors reported at time of interview: (a) time since onset of injecting drug use; (b) gender; (c) age; (d) recruitment setting (that is, treatment centre, needle exchange or street setting); and (e) frequency of injecting drugs.
↵1-152 Casual acquaintance includes drug dealer, someone in a shooting gallery or street, a fellow prisoner or a stranger.
↵1-153 The eligibility criteria was set differently for the survey conducted in 1999 compared with previous years, in that participants had to have started injecting since 1990.
↵1-150 Statistically significant at the 5% level.