#Facultyseminars: Opioid-Induced Neurotoxicity after Opioid Rotation to Methadone with Stop-and-Go Method in patients with Cancer Pain: a multicenter retrospective cohort study.

Premise:

Opioid rotation(OR) to methadone is a common strategy for managing cancer pain. However, the safety of the Stop-and-Go(SAG) method regarding neurotoxicity induced by opioids(NIO) remains uncertain.

Scope:
To identify variables associated with NIO within 14 days after opioid rotation to methadone using SAG method in patients with inadequate pain control.

Material and methods:
Multicenter retrospective cohort study in two oncology centers(January 2018-October 2022). Hospitalized cancer patients ≥18 years undergoing OR to methadone with the SAG method for pain management were included. Ethics committee approval was obtained.

Results:
372 patients were included. The mean daily morphine equivalent dose prior OR was 212.2 mg(SD 128). 58% were using fentanyl before ROP. Pain improved in 62.2% of patients after OR.
70 patients(18.8%) developed NIO after OR. Younger patients had lower rates of NIO(mean age 59.4 versus 63years; p=0.032). Women showed a trend towards lower NIO rates compared to men (13% versus 22%;p=0.065).
Patients with cognitive failure or delirium before OR presented more NIO compared to those without cognitive impairment (52.4% versus 16.8%;p<0.001).
Similar distributions of the rates of patients presenting NIO after OR were observed regarding previous tobacco use(p=0.229), alcohol consumption(p=0.270), disease stage(p=0.823), chemotherapy use in the last month(p=0.11), pain pathophysiology(p=0.567), previous doses of opioids(p=0.786), and previous opioid(p=0.876).

Conclusions:
Opioid rotation to methadone using the SAG method was associated with a low rate of NIO (<20%). These findings suggest that OR to methadone with SAG method could be considered a safe procedure, especially in younger patients and in those without cognitive impairment.

Agnès Calsina-Berna; MD, PhD.

Family and Community Medicine Specialty. Expert in Palliative Care.

PhD in Health, Welfare and Quality of Life from the University of Vic (UVic-UCC).

Attending physician in the Palliative Care Service in ICO Badalona.

Member of the ICO’s GRICOPAL Research Group. Member of the UVic-UCC Palliative Care Chair team, participating in teaching and research activities. Associate professor at the UVic-UCC Faculty of Medicine.Coordinator of the Master’s in Palliative Care ICO-UVIC

International Fellowship in Hospice and Palliative Medicine at San Diego Hospice.

Master’s in Bioethics, URL

Master’s In Palliative Care, ICO-UB

Master’s in Primary Care, UAB