Abstract
This study aims to 1) determine reported cannabis use among patients waiting for thoracolumbar surgery and to 2) identify demographics and health differences between cannabis-users and non-cannabis users.
This observational cohort study is a retrospective national multicenter review data from the Canadian Spine Outcomes and Research Network registry. Patients were dichotomized as cannabis users and non-cannabis users. Variables of interest: age, sex, BMI, smoking status, education, work status, exercise, modified Oswestry Disability Index (mODI), the Numerical Rating Scales (NRS) for leg and back pain, tingling/numbness scale, SF-12 Quality of Life Questionnaire - Mental Health Component (MCS), use of prescription cannabis, recreational cannabis, and narcotic pain medication. Continuous variables were compared using an independent t-test and categorical variables were compared using chi-square analyses.
Cannabis-use was reported by 28.4% of pre-operative patients (N=704), 47% of whom used prescription cannabis. Cannabis-use was reported most often by patients in Alberta (43.55%), British Colombia (38.09%) and New Brunswick (33.73%). Patients who reported using cannabis were significantly younger (mean=52.9 versus mean=61.21,). There was a higher percentage of concurrent narcotic-use (51.54 %) and smoking (21.5%) reported in cannabis-users in comparison to non-cannabis users (41.09%,p=0.001; 9.51%, p=0.001, respectively). There were significant differences in cannabis-use based on pathology (p=0.01). Patients who report using cannabis had significantly worse MCS scores (difference=3.93, p=0.001), and PHQ-8 scores (difference=2.51, p=0.001). There was a significant difference in work status (p=0.002) with cannabis-users reporting higher rates (20%) of being employed, but not working compared to non-cannabis users (11.13%). Non-cannabis users were more likely to be retired (45.92%) compared to cannabis-users (31.31%). There were no significant differences based on cannabis use for sex, education, exercise, NRS-back, NRS-Leg, tingling-leg, mODI, or health state.
Thoracolumbar spine surgery patients are utilizing cannabis prior to surgery both through recreational use and prescription. Patients who are using cannabis pre-operatively did not differ in regards to reported pain or disability from non-users, though they did in demographic and mental health variables.
