Details of included articles
| Author | Context | Objective | Method | Results | Authors' conclusions | Level of evidence |
|---|---|---|---|---|---|---|
| Blinderman et al 5 | USA (NYC speciality outpatient pain clinic) 53 HIV/AIDs cases with pain syndrome (36M, 17F), mostly Latino, African-American | To evaluate efficacy and safety of initiating and maintaining additional methadone for chronic pain in HIV/AIDs patients in pain including cancer pain with ongoing MMT | Retrospective chart review (March 2005–April 2006) No control group 12-month follow-up; pain measured at 1, 3, 6 and 12 months | Pain well controlled using methadone as separate agent from MMT (average NRS 9.4±1.0 at baseline, 4.2±1.4 at 12 months), initial dose 67% of total daily dose then titrated according to needs to ∼200% of MMT dose, low side effect profile. Few (13%) patients actively using heroin at 12 months | Methadone use for analgesia in addition to MMT dose improved pain levels No serious adverse events noted if titrated properly Low ongoing heroin use |
2
Retrospective cohort; relevant population, outcomes, good follow-up. However, lack of control group |
| Hines et al 11 | Australia, 1 centre, inpatient tertiary care hospital 67 case, 67 control 1:1 M:F median age 35 case 39 control | To compare pain management between MMT and non-MMT patients for an acute pain admission | Case–control restrospective chart review (1998–2004) Chronic pain excluded | Case and control did not differ in morphine dose received or pain report per day There is trend that those with no methadone dose increase are more likely to discharge AMA MMT patients have more behavioural problems than non-MMT | Inadequate analgesia leads to behavioural problems and premature discharge |
2
Retrospective case–control, however, less relevant comparison for the current research question; does not compare pain management strategies in MMT patients |
| Hoffman et al 16 | USA, NY N=2, 32M, 37M | To discuss pain management in opioid-addicted patients with cancer and its challenges | Case series (1991) | Use of methadone as analgesia by increasing dose and frequency of administration | Early psychiatric intervention is important aside from pharmacological interventions |
3
Case series with no comparison |
| Manfredi et al 12 | USA, cancer centre, NY 6 cases (3M,3F) age: 34–55 | Demonstrate use of methadone for acute pain in MMT patients with cancer | Case series (2001) Compared pain control before and after use of methadone for analgesia | Aggressive titration of methadone provides pain relief in opioid refractory pain with no adverse effects | Use methadone early, low threshold to titrate aggressively or switch to methadone |
3
Case series, pre–post comparison with high risk of bias |
| Ostgathe et al 15 | Germany N=1, 38 years/F palliative care IPU | To present the pain management in an opioid-addicted patient with cancer and the challenges | Case report (2008) | High doses of l- methadone were needed initially, followed by signs of opioid-toxicity, followed by adequate control at lower doses. Adjuvant regimens and IDT approach were also used | Difficult to determine substance abuse relapse versus pseudoaddiction; use of l-methadone at high dose can achieve good pain control with adjuvant modalities |
3
Single case without comparison (no other opioid attempted) |
| Rowley et al 14 | Dublin, Ireland Palliative care referrals,1 centre (8M, 4F) Age: 24–62 | To review the use of opioids for analgesia in MMT patients and present case series | Chart review 2006–2010 | It was difficult to control patients’ pain, multiple agents required in 70% Methadone used in only 1/12 | IDT approach should be used Methadone is underused and should be used early for these patients |
3
Case series; no comparison between methadone and other opioid analgesics, dose and frequency of methadone not specified |
| Sulistio and Jackson13 | Australia N=1, 48M Hospice IPU | To describe the difficulty in treating pain in terminally ill cancer patient on MMT To review current guidelines | Case report (2013) | Used increased methadone doses given at frequent intervals; also used ketamine and adjuvants | It is challenging to determine an appropriate starting dose for breakthrough; MTT patients require larger, more frequent dosing even in face for risk of relapse |
3
Case report; did not compare use of methadone versus other opioids, did not achieve good, lasting pain control |