TABLE 3.
Unadjusted and adjusted Cox regression of the association between baseline fentanyl UDT and time to (a) assigned or (b) any MOUD discontinuation among 209 people with POUD in the OPTIMA trial who initiated treatment
| Assigned MOUD discontinuation | Any MOUD discontinuation | |||
|---|---|---|---|---|
| Unadjusted HR (95% CI) | Adjusted HR†‡ (95% CI) | Unadjusted HR (95% CI) | Adjusted HR†‡ (95% CI) | |
| Main explanatory variable | ||||
| UDT positive for fentanyl at baseline | 3.61 (2.52–5.17)* | 1.23 (0.73–2.06) | 3.32 (2.30–4.80)* | 1.35 (0.78–2.33) |
| Assigned MOUD | ||||
| Buprenorphine/naloxone (versus methadone) | 1.28 (0.91–1.79) | 1.44 (0.99–2.08) | 1.04 (0.73–1.48) | 1.10 (0.75–1.62) |
| Socio-demographics | ||||
| Age (per year older) | 0.98 (0.97–1.00)* | 0.98 (0.96–0.99) | 0.99 (0.97–1.00)* | 0.99 (0.97–1.01) |
| Male sex | 0.65 (0.46–0.92)* | 0.65 (0.46–0.94)* | ||
| White (versus BIPOC) | 0.52 (0.37–0.75)* | 1.00 (0.68–1.48) | 0.53 (0.37–0.67)* | 0.85 (0.56–1.29) |
| High school education or higher | 1.18 (0.76–1.85) | 1.05 (0.67–1.65) | ||
| Comorbidities | ||||
| BDI-II score (per 1 point higher) | 1.01 (1.00–1.02) | 1.01 (0.99–1.02) | ||
| BPI severity score (per 1 point higher) | 0.99 (0.94–1.05) | 0.99 (0.93–1.06) | ||
| BPI interference score (per 1 point higher) | 1.01 (0.96–1.06) | 1.01 (0.95–1.06) | ||
| Substance use related factors | ||||
| Life-time heroin use | 1.76 (0.21–2.57)* | 1.20 (0.75–1.92) | 1.59 (1.08–2.34)* | |
| OUD moderate/severe (versus mild) | 0.93 (0.35–2.53) | 0.80 (0.29–2.16) | ||
| UDT positive for opioids (excluding fentanyl) | 0.67 (0.42–1.05)* | 0.72 (0.45–1.15) | ||
| UDT positive for stimulants (cocaine/amphetamines) | 3.07 (2.09–4.50)* | 1.62 (0.97–2.71) | 2.93 (1.97–4.38)* | 1.60 (0.93–2.76) |
| UDT positive for benzodiazepines | 0.53 (0.30–0.91)* | 0.76 (0.43–1.35) | 0.55 (0.31–0.97)* | |
| UDT positive for THC | 0.95 (0.68–1.33) | 0.91 (0.64–1.29) | ||
| Alcohol intoxication last 30 days | 0.73 (0.45–1.17) | 0.71 (0.43–1.15) | ||
| Health-care-related factors | ||||
| Prior enrolment in MOUD (ref: no) | ||||
| Yes, same as assigned MOUD | 1.77 (1.22–2.57)* | 1.77 (1.21–2.59)* | ||
| Yes, different from assigned MOUD | 1.63 (1.00–2.66)* | 1.26 (0.74–2.13) | ||
| Structural-level factors* | ||||
| Province (ref: British Columbia) | ||||
| Alberta | 0.63 (0.42–0.97)* | 0.52 (0.32–0.83) | 0.70 (0.45–1.0.8) | |
| Ontario | 0.38 (0.24–0.61)* | 0.45 (0.25–0.80) | 0.46 (0.29–0.74)* | |
| Quebec | 0.11 (0.06–0.19)* | 0.15 (0.07–0.30) | 0.12 (0.07–0.22)* | |
| Current homelessness | 1.84 (1.30–2.59)* | 2.10 (1.47–2.99)* | 1.18 (0.77–1.80) | |
| Employment last 30 days | 0.68 (0.47–1.00)* | 0.82 (0.54–1.23) | 0.65 (0.44–0.97)* | 0.76 (0.47–1.20) |
BIPOC = black, Indigenous and people of colour; OUD = opioid use disorder; UDT = urine drug test; THC = Δ−9-tetrahydrocannabinol; BDI-II = Beck Depression Index, version 2; BPI = Brief Pain Inventory; MOUD = medication for opioid use disorder; HR = hazard ratio; OPTIMA = Optimal Personalized Treatment of early breast cancer using Multi-parameter Analysis; POUD = prescription-type opioid use disorder.
P < 0.10 in the unadjusted analyses and considered for inclusion in the multivariable model.
Only the variables included in the final multivariable confounder model are presented in this column.
Models also adjusted for calendar-year of enrolment and assigned MOUD.