Table 3.
Segmented regression analysis of the impact of opioid agonist therapy on different types of substance use among 1107 people who use illicit drugs in Vancouver, British Columbia, Canada.
| Estimated prevalence, % (95% confidence interval) | ||||
|---|---|---|---|---|
| Substance type | Baseline a | Before OAT initiation | After OAT initiation | End of study b |
| Heroin | 64.8 (61.3, 68.1) | 84.2 (82.5, 85.8) | 70.6 (68.9, 72.3) | 43.4 (41.2, 45.6) |
| Illicit prescription opioid | 29.6 (26.7, 32.8) | 39.7 (37.3, 42.1) | 28.7 (26.9, 30.5) | 18.9 (17.3, 20.6) |
| Cocaine | 61.2 (57.8, 64.4) | 55.3 (52.8, 57.7) | 49.4 (47.4, 51.3) | 30.1 (28.2, 32.1) |
| Crack cocaine | 51.9 (48.5, 55.2) | 47.4 (45.0, 49.9) | 48.9 (46.9, 50.8) | 54.8 (52.6, 56.9) |
| Crystal methamphetamine | 13.6 (11.5, 16.0) | 20.0 (18.1, 22.1) | 19.0 (17.5, 20.6) | 14.8 (13.4, 16.4) |
| Cannabis | 57.0 (53.6, 60.3) | 52.1 (49.7, 54.6) | 51.3 (49.4, 53.2) | 45.7 (43.5, 47.9) |
| Daily alcohol | 15.1 (12.7, 17.8) | 9.6 (8.3, 11.1) | 8.1 (7.2, 9.3) | 9.3 (8.1, 10.7) |
| Benzodiazepines | 15.8 (13.4, 18.5) | 13.2 (11.7, 14.9) | 8.4 (7.3, 9.6) | 2.4 (1.9, 3.0) |
OAT opioid agonist therapy.
a
The first observation upon joining cohort.
b
At five years post opioid agonist therapy enrolment.