Prescription medications dispensed following a nontraumatic spinal cord dysfunction: a retrospective population-based study in Ontario, Canada

Study design — Retrospective cohort study.

Objectives — To examine the prevalence of polypharmacy for individuals with nontraumatic spinal cord dysfunction (NTSCD) following inpatient rehabilitation and to determine associated risk factors.

Setting — Ontario, Canada.

Methods — Administrative data housed at ICES, Toronto, Ontario were used. Between 2004 and 2015, we investigated prescription medications dispensed over a 1-year period for persons following an NTSCD-related inpatient rehabilitation admission. Descriptive and analytical statistics were conducted. Using a robust Poisson multivariable regression model, relative risks related to polypharmacy (ten or more drug classes) were calculated. Main independent variables were sex, age, income quintile, and continuity of care with outpatient physician visits.

Results — We identified 3468 persons with NTSCD during the observation window. The mean number of drug classes taken post-inpatient rehabilitation was 11.7 (SD = 6.0), with 4.0 different prescribers (SD = 2.5) and 1.8 unique pharmacies (SD = 1.0). Significant predictors for post-discharge polypharmacy were: being female, lower income, higher comorbidities prior to admission, lower Functional Independence Measure at discharge, previous number of medication classes dispensed in year prior to admission, and lower continuity of care with outpatient physician visits. The most common drugs dispensed post-inpatient rehabilitation were antihypertensives (70.0%), laxatives (61.6%), opioids (59.5%), and antibiotics (57.8%).

Conclusion — Similar to previous research with traumatic spinal cord injury, our results indicate that polypharmacy is prevalent among persons with NTSCD. Additional research examining medication therapy management for NTSCD is suggested.