Table 1:

Baseline demographic and clinical characteristics of patients, overall and by opioid agonist therapy initiation within 7 days of discharge from index emergency department visit or hospital admission for an opioid toxicity event

Participant characteristicsOverall no. (%) of patients
n = 20 702
No. (%) of patients who initiated OAT
n = 851
No. (%) of patients who did not initiate OAT
n = 19 851
Standardized difference
Age, yr, median (IQR)35 (27–48)32 (27–41)35 (27–48)0.23
Age category, yr
 0–243129 (15.1)142 (16.7)2987 (15.0)0.04
 25–346837 (33.0)343 (40.3)6494 (32.7)0.16
 35–444665 (22.5)208 (24.4)4457 (22.5)0.05
 45–645185 (25.0)144 (16.9)5041 (25.4)0.21
 ≥ 65886 (4.3)14 (1.6)872 (4.4)0.16
Sex
 Female7227 (34.9)279 (32.8)6948 (35.0)0.05
 Male13 475 (65.1)572 (67.2)12 903 (65.0)0.05
Location of residence
 Urban18 614 (89.9)763 (89.7)17 851 (89.9)0.01
 Rural1738 (8.4)67 (7.9)1671 (8.4)0.02
 Missing data350 (1.7)21 (2.5)329 (1.7)0.06
Neighbourhood income quintile
 1 (lowest)8284 (40.0)298 (35.0)7986 (40.2)0.11
 24609 (22.3)175 (20.6)4434 (22.3)0.04
 33149 (15.2)148 (17.4)3001 (15.1)0.06
 42255 (10.9)91 (10.7)2164 (10.9)0.01
 5 (highest)2030 (9.8)116 (13.6)1914 (9.6)0.12
 Missing data375 (1.8)23 (2.7)352 (1.8)0.06
Johns Hopkins Aggregate Diagnosis Group (≤ 2 yr)
 0–55633 (27.2)228 (26.8)5405 (27.2)0.01
 6–96598 (31.9)292 (34.3)6306 (31.8)0.05
 ≥ 108471 (40.9)331 (38.9)8140 (41.0)0.04
 Infective endocarditis155 (0.7)9 (1.1)146 (0.7)0.03
 HIV321 (1.6)7 (0.8)314 (1.6)0.07
 Hepatitis C3011 (14.5)143 (16.8)2868 (14.4)0.06
Mental health diagnoses
 Anxiety4757 (23.0)201 (23.6)4556 (23.0)0.02
 Deliberate self-harm6022 (29.1)254 (29.8)5768 (29.1)0.02
 Mood disorder3378 (16.3)109 (12.8)3269 (16.5)0.10
 Schizophrenia and other psychotic disorders1852 (8.9)52 (6.1)1800 (9.1)0.11
 Other mental health disorders1863 (9.0)75 (8.8)1788 (9.0)0.01
Emergency department visit or hospital admission for opioid toxicity in past 1 yr5912 (28.6)302 (35.5)5610 (28.3)0.16
OAT in past 1 yr
 Any4989 (24.1)455 (53.5)4534 (22.8)0.66
 Methadone3442 (16.6)327 (38.4)3115 (15.7)0.53
 Buprenorphine–naloxone2281 (11.0)219 (25.7)2062 (10.4)0.41
 Slow-release oral morphine92 (0.4)13 (1.5)79 (0.4)0.12
Ontario Marginalization Index
Residential instability
 1 (least marginalized)1530 (7.4)67 (7.9)1463 (7.4)0.02
 22136 (10.3)106 (12.5)2030 (10.2)0.07
 33064 (14.8)135 (15.9)2929 (14.8)0.03
 44642 (22.4)199 (23.4)4443 (22.4)0.02
 5 (most marginalized)8685 (42.0)312 (36.7)8373 (42.2)0.11
 Missing data645 (3.1)32 (3.8)613 (3.1)0.04
Material deprivation
 1 (least marginalized)2220 (10.7)118 (13.9)2102 (10.6)0.10
 22637 (12.7)116 (13.6)2521 (12.7)0.03
 33118 (15.1)135 (15.9)2983 (15.0)0.02
 44090 (19.8)166 (19.5)3924 (19.8)0.01
 5 (most marginalized)7992 (38.6)284 (33.4)7708 (38.8)0.11
 Missing data645 (3.1)32 (3.8)613 (3.1)0.04
Years
 2013–20142622 (12.9)68 (8.0)2594 (13.1)0.17
 2015–20163494 (16.9)110 (12.9)3384 (17.0)0.12
 2017–20188224 (39.7)340 (40.0)7884 (39.7)0.00
 2019–20206322 (30.5)333 (39.1)5989 (30.2)0.19
  • Note: IQR = interquartile range, OAT = opioid agonist therapy.

  • * Patients who experienced multiple toxic events during the study period were counted each time.

  • Unless otherwise indicated.