Table 1 Basic characteristics of 595 opioid agonist therapy patients (numbers (n) and percentages (%)):

Age (years), n (%)

 18-30

57 (10)

 30-40

169 (28)

 40-50

193 (32)

 50-60

10 (23)

 ≥ 60

36 (6)

 Mean (SD)

44 (10)

Sex, n (%)

 Male

420 (71)

 Female

175 (29)

Highest level of education, n (%)

 Not completed primary school

30 (5)

 Completed primary school (9 years)

266 (45)

 Completed high school (12 years)

243 (41)

 ≤ 3 years of college or university

46 (8)

 > 3 years of college or university

10 (2)

 Number of years in opioid agonist therapy, mean (SD)

8 (5)

 Injecting substance use past 30 days, n (%)

181 (30)

 Unstable housing past 30 days^a), n (%)

58 (10)

Substances used past 30 days^b), n (%)

 Cannabis

396 (67)

 Benzodiazepines

354 (60)

 Alcohol

349 (59)

 Amphetamines

249 (42)

 Opioids

123 (21)

 Cocaine

25 (4)

 Mean age for the onset of substance use (mean (SD))

13 (2)

Comorbidities, n (%)

 Hepatitis C virus infection

350 (59)

 Hepatitis B virus infection

< 5 (< 1)

 Human immunodeficiency virus

< 5 (< 1)