An increase in overdose mortality during the first 2 weeks after entering or re‐entering methadone treatment in Amsterdam

Abstract

Inhaling heroin, common among Amsterdam heroin users, is thought to account for low OD mortality rates both during and after treatment. Accumulation of methadone, inadequate assessment of tolerance of known clients re-entering treatment and concurrent periods of stress or extreme heroin use when entering treatment are mentioned as possible explanations of the increased risk within the first 2 weeks. An Australian study reported a much higher increase. The modest increase in Amsterdam is explained by low background risk of overdose mortality, low starting dosage and the low threshold to treatment.

The impact of buprenorphine and methadone on mortality: a primary care cohort study in the United Kingdom

“…Prolonged OST is associated with improved survival 5; however, recent studies highlight very high mortality risk in the month after treatment cessation 20, 21, 22, 23. There have also been reports of an elevated risk of mortality during the first month of OST 20, 21, 24, 25.…”

Risk of drug-related mortality during periods of transition in methadone maintenance treatment: A cohort study

“…the first two weeks in treatment, the first thirty days off treatment) were chosen based on published evidence. (Buster, et al, 2002;Davoli, et al, 2007) A different choice of high risk periods may influence the relative importance of the different risk factors associated with mortality. As mortality was a relatively rare event, this study may have been underpowered to detect potentially significant contributions of some factors.…”

“…Patients were defined by their treatment status at the end of the study or at the time of death. Treatment status was defined according to previous studies (Buster, et al, 2002;Davoli, et al, 2007;Degenhardt, et al, 2009) as : 1-2 weeks in treatment; 3-10 weeks in treatment; >10 weeks in treatment; ≤ 30 days off treatment; > 30 days off treatment.…”

“…(Cairns, Roberts, & Benbow, 1996;Drummer, Opeskin, Syrjanen, & Cordner, 1992;Harding-Pink, 1993;Morgan, et al, 2006) The risk of overdose has been shown to vary over the course of MMT, with several studies reporting an elevated risk of fatal overdose in the initial weeks of MMT. (Buster, van Brussel, & van den Brink, 2002;Caplehorn & Drummer, 1999;Degenhardt, et al, 2009;Perret, Deglon, Kreek, Ho, & La Harpe, 2000;Deborah Zador & Sunjic, 2000) These effects may arise due to inadequate clinical assessment and review of a patients" tolerance prior to initiating methadone, thus resulting in overdose. (Buster, et al, 2002;Caplehorn & Drummer, 1999) Therefore cautious prescribing of methadone during the first two weeks has been advised based on the risk of cumulative toxicity from methadone.…”

“…(Buster, van Brussel, & van den Brink, 2002;Caplehorn & Drummer, 1999;Degenhardt, et al, 2009;Perret, Deglon, Kreek, Ho, & La Harpe, 2000;Deborah Zador & Sunjic, 2000) These effects may arise due to inadequate clinical assessment and review of a patients" tolerance prior to initiating methadone, thus resulting in overdose. (Buster, et al, 2002;Caplehorn & Drummer, 1999) Therefore cautious prescribing of methadone during the first two weeks has been advised based on the risk of cumulative toxicity from methadone. (Zador & Sunjic, 2000) The risk of methadone overdose must be balanced against the risk of newly inducted patients resorting to illicit drug use to compensate for withdrawal symptoms as they wait for the stabilising effects of methadone to take effect.…”