Oral Presentation NSW State Cancer Conference 2023

Quality of life and pain outcomes for cancer patients prescribed medicinal cannabis: the QUEST Initiative 12-month results (#15)

Margaret-Ann Tait 1 2 , Daniel SJ Costa 1 , Kate White 2 , Rachel Campbell 1 , Claudia Rutherford 2
  1. School of Psychology, University of Sydney, Sydney, NSW, Australia
  2. Sydney Nursing School, University of Sydney, Sydney, NSW, Australia

Introduction

Since 2018, more than 11,000 Australian patients have received medicinal cannabis prescriptions for cancer-related pain and symptoms.1 However, reporting of patient-reported outcomes associated with medicinal cannabis use in clinical practice is limited. We aimed to assess changes in overall health-related quality of life (HRQL), pain intensity, and pain interference, for cancer patients prescribed medicinal cannabis.

Methods

This sub-study includes patients with any cancer diagnosis recruited to the QUEST Initiative; a longitudinal observational study of patients prescribed medicinal cannabis oil between Nov2020-Dec2021, by 117 clinicians across Australia. Outcomes were assessed using EORTC QLQ-C302, PROMIS Scale v1.0 - Pain Intensity 3a3, and PROMIS Short Form v1.0 - Pain Interference 8a4, pre-treatment, after 2-week titration, then 1-,2-,3-,5-,7-,9-, and 12-months post-titration. Change over time was analysed using linear mixed models adjusted for age and gender.

Results

Of 127 eligible cancer patients, 89 consented and completed both baseline and at least one follow-up questionnaire. Participants were between 33 and 91 years old mean age 61.8 years (SD:13.3), and 56.2% were female. Most common diagnoses were breast cancer (27/89, 30%) and prostate cancer (16/89, 18%) and most participants were prescribed medicinal cannabis for pain (76/89, 85%), particularly musculoskeletal pain in joints, bones, muscle, or tendons (30/89, 34%) and cancer pain caused by the cancer itself or its treatment (25/89, 28%). Questionnaire completion rates for each timepoint ranged between 88% at 1 month to 29% at 1 year. Statistically significant improvements in QLQ-C30 Summary scores were observed at all follow-up timepoints compared with baseline, and from baseline to mean follow-up (MD=6.37, SD=14.96; t(437)=4.02, p<0.001). In the absence of formal guidelines for interpreting within group change for QLQ-C30 summary scores, Cohen’s d 0.43 indicated a small to medium improvement in HRQL. Pain Intensity T-scores improved from baseline to mean follow-up (MD=3.23, SD=6.45; t(366)=4.45, p<0.001), and Pain interference T-scores improved similarly (MD=3.10, SD=8.23; t(341)=3.34, p<0.001). Following PROMIS interpretation guidelines, improvements in pain outcomes were clinically meaningful (>3 T-scores).

Conclusions

We observed clinically meaningful improvements in pain outcomes and small to medium improvements in HRQL for cancer patients prescribed medicinal cannabis in a real-world setting over 12 months. Findings suggest prescribing medicinal cannabis may alleviate cancer patients’ pain symptoms and improve HRQL while allowing clinicians to monitor adverse events, prevent drug-drug interactions, and avoid risks of cannabis abuse through self-medicating. Lack of control group limits interpretation of the results.

  1. Therapeutic Goods Administration (TGA) (2023). Medicinal cannabis Special Access Scheme Category B data: SAS-B Indications. Accessed 12 April 2023. https://www.tga.gov.au/products/unapproved-therapeutic-goods/medicinal-cannabis-hub/medicinal-cannabis-access-pathways-and-patient-access-data/medicinal-cannabis-special-access-scheme-category-b-data
  2. Aaronson, N.K., et al., The EORTC QLQ-C30: a quality-of-life instrument for use in international clinical trials in oncology. J Natl Cancer Inst, 1993. 85(5): p. 365-76.
  3. Cella D, et. al., on behalf of the PCG. The Patient-Reported Outcomes Measurement Information System (PROMIS): Progress of an NIH Roadmap Cooperative Group During its First Two Years. Medical Care. 2007;45(5).
  4. Chen CX, Kroenke K, Stump T, Kean J, Krebs EE, Bair MJ, Damush T, Monahan PO. Comparative Responsiveness of the PROMIS Pain Interference Short Forms With Legacy Pain Measures: Results From Three Randomized Clinical Trials. The journal of pain : official journal of the American Pain Society. 2019;20(6):664-75.