Results of sensitivity analyses of the cost-effectiveness of diacetylmorphine compared with methadone in the treatment of refractory opioid dependence over a lifetime horizon
| Analysis; treatment | Cost, Can$ × 1000, mean (95% CI) | Cost component, % total | QALYs, mean (95% CI) | Incremental cost-effectiveness ratio, Can$ × 1000 per QALY gained, mean (95% CI) | ||
|---|---|---|---|---|---|---|
| Treatment | Health resources utilization | Criminal activity and charges | ||||
| Third-party payer perspective* | ||||||
| Diacetylmorphine | 971.5 (642.1–1489.9) | 10.5 | 15.7 | 73.8 | 7.92 (7.32–8.53) | CS (CS–129.9) |
| Methadone | 993.6 (635.6–1546.3) | 2.4 | 18.9 | 78.7 | 7.46 (6.91–8.01) | |
| Ministry of Health perspective† | ||||||
| Diacetylmorphine | 247.6 (170.8–401.9) | 41.1 | 58.9 | – | 7.92 (7.32–8.53) | 85.6 (CS–363.1) |
| Methadone | 208.0 (113.9–386.3) | 12.1 | 87.9 | – | 7.46 (6.91–8.01) | |
| Diacetylmorphine not available after initial relapse | ||||||
| Diacetylmorphine | 1112.9 (727.2–1743.0) | 5.9 | 15.3 | 78.8 | 7.71 (7.15–8.26) | CS (CS–95.9) |
| Methadone | 1137.6 (736.8–1776.5) | 2.1 | 16.7 | 81.2 | 7.46 (6.91–8.01) | |
| Assumed no change in lengths of treatment/relapse episodes after first cycle | ||||||
| Diacetylmorphine | 1105.3 (730.7–1732.7) | 8.8 | 14.5 | 76.7 | 7.81 (7.21–8.43) | CS (CS–105.6) |
| Methadone | 1155.4 (748.2–1825.0) | 1.9 | 17.3 | 80.8 | 7.29 (6.77–7.81) | |
| Time to discontinuation of relapse for diacetylmorphine from NAOMI trial data | ||||||
| Diacetylmorphine | 1018.7 (673.4–1629.1) | 13.0 | 10.8 | 76.1 | 8.58 (7.87–9.29) | CS (CS–847.5) |
| Methadone | 1042.6 (664.1–1678.3) | 3.1 | 14.0 | 82.9 | 8.18 (7.32–9.09) | |
| Time to discontinuation of post-diacetylmorphine methadone for diacetylmorphine from NAOMI trial data | ||||||
| Diacetylmorphine | 1113.3 (739.7–1728.5) | 9.2 | 14.6 | 76.2 | 7.79 (7.18–8.40) | CS (CS–106.7) |
| Methadone | 1172.9 (759.1–1864.5) | 1.7 | 17.7 | 80.6 | 7.19 (6.68–7.71) | |
| Exponential distributions set for time to discontinuation curves | ||||||
| Diacetylmorphine | 1103.5 (728.7–1712.1) | 7.9 | 15.2 | 76.9 | 7.77 (7.14–8.44) | CS (CS–330.7) |
| Methadone | 1145.5 (737.8–1812.3) | 2.0 | 17.1 | 80.9 | 7.38 (6.78–8.06) | |
| Probability of HIV seroconversion set to zero | ||||||
| Diacetylmorphine | 1017.9 (652.7–1624.6) | 10.0 | 7.3 | 82.7 | 7.94 (7.33–8.54) | CS (CS–147.1) |
| Methadone | 1039.3 (647.1–1692.6) | 2.3 | 8.6 | 89.1 | 7.46 (6.91–8.02) | |
| Discount rate 0% | ||||||
| Diacetylmorphine | 1802.9 (1114.6–3040.9) | 8.6 | 15.8 | 75.5 | 12.16 (11.04–13.37) | CS (CS–223.4) |
| Methadone | 1837.5 (1128.1–3112.3) | 2.0 | 18.3 | 79.7 | 11.29 (10.27–12.37) | |
| Discount rate 3% | ||||||
| Diacetylmorphine | 1317.7 (850.0–2116.7) | 9.0 | 14.7 | 76.2 | 9.28 (8.52–10.07) | CS (CS–143.1) |
| Methadone | 1358.9 (863.6–2191.4) | 2.1 | 17.3 | 80.6 | 8.69 (8.00–9.41) | |
| Equalize mortality in methadone state to mortality in diacetylmorphine state (using diacetylmorphine estimates) | ||||||
| Diacetylmorphine | 1091.2 (721.5–1703.7) | 9.3 | 14.1 | 76.6 | 7.89 (7.29–8.53) | CS (CS–115.4) |
| Methadone | 1118.1 (724.7–1758.9) | 2.1 | 16.7 | 81.2 | 7.35 (6.86–7.87) | |
| Mortality estimates from Grönbladh et al. (36) | ||||||
| Diacetylmorphine | 941.2 (640.8–1435.4) | 10.3 | 13.5 | 76.2 | 7.33 (6.65–8.01) | 44.8 (CS–146.6) |
| Methadone | 904.2 (604.4–1377.4) | 2.4 | 16.2 | 81.4 | 6.50 (6.09–6.90) | |
| Treatment starting age 30 yr | ||||||
| Diacetylmorphine | 1292.7 (966.5–1736.6) | 9.5 | 13.1 | 77.4 | 10.27 (9.69–10.85) | CS (CS–123.1) |
| Methadone | 1345.1 (965.5–1852.2) | 2.2 | 15.3 | 82.5 | 9.83 (9.27–10.38) | |
| Treatment starting age 50 yr | ||||||
| Diacetylmorphine | 840.7 (421.7–1653.9) | 9.4 | 15.1 | 75.4 | 5.37 (4.82–5.94) | CS (CS–148.3) |
| Methadone | 864.3 (420.4–1754.2) | 2.1 | 18.3 | 79.6 | 4.92 (4.40–5.46) | |
| Treatment-specific cost and utilities | ||||||
| Diacetylmorphine | 1109.3 (712.1–1754.0) | 9.3 | 13.1 | 77.6 | 7.99 (7.41–8.60) | CS (CS–417.3) |
| Methadone | 1229.2 (790.0–1838.1) | 2.0 | 15.8 | 82.2 | 7.38 (6.81–7.98) | |
| No improvement in health- related quality of life from treatment to abstinence | ||||||
| Diacetylmorphine | 1096.1 (724.1–1707.2) | 9.3 | 14.1 | 76.7 | 7.90 (7.28–8.52) | CS (CS–131.3) |
| Methadone | 1137.6 (736.8–1776.5) | 2.1 | 16.7 | 81.2 | 7.46 (6.90–8.01) | |
Note: CI = credibility interval, CS = cost saving, NAOMI = North American Opiate Medication Initiative, QALY = quality-adjusted life-year.
↵* Third-party payer perspective includes costs borne by the health care and criminal justice systems but excludes out-of-pocket costs borne by society.
↵† Ministry of Health perspective includes only costs incurred by the health care system.