To assess the prevalence and potential risk factors for polypharmacy and prescribing of the potentially inappropriate medications (PIMs), opioids and benzodiazepines/Z-drugs, in older adults with systemic lupus erythematosus (SLE).
Population comprised of adults aged ≥50 years meeting ACR or SLICC SLE classification criteria followed at a tertiary care rheumatology clinic. Information on prescriptions filled in the 4 months preceding chart review was obtained from the Manitoba Drug Program Information Network (DPIN). Clinical data, including age, sex, Charlson Co-morbidity Index (CCI), SLE disease activity (SLEDAI-2K), prednisone use, SLE duration, and rural residence were abstracted from electronic medical records. Logistic regression analyses were performed to assess any association between polypharmacy (2 definitions: ≥5 and ≥10 medications), PIM use, and clinical features.
206 patients (mean age 62 years, 91% female, 36% rural) included: 148(72%) filled ≥5 medications, 71(35%) ≥10 medications, 63(31%) used benzodiazepines/Z-drugs, and 50(24%) used opioids. Among the 77 patients ≥65 years old, 57(74%) filled ≥5 medications and 26(34%), ≥10 medications compared to 30% and 4%, respectively, of Manitobans ≥65 years old (NPDUIS, 2016). The odds of polypharmacy were greater with prednisone use (adjusted OR 3.70, 95% CI 1.40-9.79 for ≥5 medications), CCI (1.62, 1.20-2.17), and rural residence (2.05, 1.01-4.18). Odds of benzodiazepine/Z-drug use were increased with polypharmacy (4.35, 1.69-11.22); opioid use, with polypharmacy (6.75, 1.93-23.69) and CCI (1.29, 1.08-1.54).
The prevalence of polypharmacy in this SLE cohort is higher than in the general Manitoban population. Polypharmacy is a strong marker for use of prescription benzodiazepines/Z-drugs and opioids.