The greater the pleiotropic effects, the greater the benefits - cannabis as a “biopsychosocial” drug: a mixed-methods study on chronic non-cancer pain

Against the background of widely inconsistent data from randomized controlled trials (RCT), the use of cannabis-based medicines (CBM) from the perspective of patients with chronic non-cancer pain (CNCP) was described. Based on a purposive/convenient sampling, patients were recruited from the Pain Clinic of Hannover Medical School who had been using CBM prescribed by a doctor for at least 6 months. The patients discussed their experiences with CBM in semi-structured individual interviews. The interview transcripts were coded and analyzed using a modified grounded theory approach with the help of MAXQDA®. In addition, the Treatment Satisfaction Questionnaire with Medication (TSQM) was used. Theoretical saturation was reached after 32 interviews. Open and selective coding revealed the overarching phenomenon of “subjective pain experience under CBM therapy”, with one of the main themes being the “effect of CBM”. This revealed the categories “effect on pain” and “psychological” and “somatic effect”. The most important concepts were “pain intensity”, “pain management”, “stress management”, “musculoskeletal system”, and “sleep quality.” Constructing a theoretical framework 4 groups of responses to CBM treatment were identified. The focus is either on (I) pain reduction, (II) pain coping, (III) reduced stress or (IV) multidimensional aspects. When this classification was applied to topic of quality of life (QOL), the greatest effectiveness and highest overall satisfaction were found in group (IV). Mixed methods showed a continuous increase in the perceived effectiveness of CBM on pain-centered complaints from group (I) to (IV). In line with the biopsychosocial understanding of chronic pain, it appears that those CNCP patients who benefit most from CBM are those who show the most far-reaching effects on both a physical and psychological level. The pleiotropic effects of CBM may be responsible for this. Based on these results, interdisciplinary prospective research appears sensible and necessary to further and systematically investigate this clinically relevant topic. This study was registered with the German Clinical Trials Register (DRKS00037434), after approval by the local ethics committee (No. 8391_B0-K_2019).