Table 2 Cox proportional hazards regression models of overdose and emergency department (ED) / hospitalization outcomes (N = 3293)

Number with event (%)

 Treatment setting

  Outpatient

32 (1.4%)

297 (12.7%)

1446 (61.9%)

  Residential

24 (2.5%)

147 (15.4%)

717 (74.9%)

Adjusted HR (95% CI)

 Treatment setting

  Outpatient

ref

ref

–

  Residential

1.39 (0.73–2.64)

1.02 (0.80–1.29)

–

  Outpatient < 14 days post-admission

–

–

Ref

  Residential < 14 days post-admission

–

–

2.48 (1.98–3.11)

  Outpatient 14 + days post-admission

–

–

Ref

  Residential 14 + days post-admission

–

–

1.25 (1.12–1.41)

 Gender

  Male

Ref

Ref

Ref

  Female

0.84 (0.48–1.49)

1.44 (1.19–1.75)

1.36 (1.24–1.48)

 Race

  White

Ref

Ref

Ref

  Black or African American

0.83 (0.10–6.89)

0.53 (0.20–1.42)

1.29 (0.92–1.81)

  Alaska Native/American Indian

1.62 (0.39–6.83)

1.38 (0.86–2.20)

1.13 (0.89–1.43)

  Other single race

1.92 (0.58–6.30)

1.59 (1.01–2.51)

1.08 (0.85–1.36)

  Two or more races

1.16 (0.60–2.25)

0.91 (0.72–1.16)

1.04 (0.93–1.17)

 Age

  18–29

Ref

Ref

Ref

  30–39

1.57 (0.80–3.07)

0.92 (0.73–1.15)

0.98 (0.89–1.08)

  40 + 

2.02 (1.02–3.98)

0.98 (0.77–1.26)

1.09 (0.97–1.22)

 Elixhauser score

1.03 (0.99–1.07)

1.02 (1.00–1.03)

1.00 (1.00–1.01)

 Substances used

  Heroin

1.77 (0.54–5.76)

1.41 (0.96–2.08)

0.92 (0.78–1.08)

  Rx opioid

0.71 (0.29–1.74)

0.82 (0.61–1.11)

1.16 (1.01–1.33)

  Methadone

0.97 (0.13–7.34)

0.55 (0.24–1.26)

0.78 (0.58–1.06)

  Alcohol

1.62 (0.89–2.95)

0.94 (0.73–1.22)

1.02 (0.91–1.14)

  Stimulant

0.43 (0.22–0.85)

0.90 (0.73–1.11)

1.12 (1.02–1.24)

 Injection opioid use

1.54 (0.77–3.08)

1.44 (1.14–1.81)

1.25 (1.13–1.39)

 Opioid use frequency

  Not in last month

Ref

Ref

Ref

  Use in past week-month

3.63 (1.33–9.95)

1.38 (1.00–1.89)

1.06 (0.92–1.21)

  Daily

2.22 (0.84–5.89)

1.39 (1.05–1.83)

1.04 (0.93–1.17)

 Prior inpatient medically supervised withdrawal

1.44 (0.75–2.77)

1.23 (0.94–1.59)

1.11 (0.98–1.26)

 MOUD use

0.45 (0.23–0.89)

0.96 (0.78–1.20)

0.84 (0.76–0.93)

 Prior all-cause ED/hospitalization

0.76 (0.41–1.40)

1.33 (1.08–1.64)

1.83 (1.67–2.01)

 Prior opioid-related ED/hospitalization

2.16 (1.03–4.52)

1.72 (1.31–2.26)

0.94 (0.81–1.09)