Prevalence of opioid dispensings and concurrent gastrointestinal medications in an elderly population from Ontario, Canada.

BACKGROUND: Although opioid analgesics are effective therapeutic agents, gastrointestinal (GI) side effects represent a challenging consequence of treatment. In an elderly population, age-related physiological changes, such as decreased GI functioning and dehydration, may compound the adverse effects of opioids; therefore, appropriate prophylactic treatment, utilizing laxatives and/or acid suppressants, is particularly important in an elderly population.

AIM: This study describes the prevalence of outpatient opioid dispensings and the concomitant dispensing of opioids and GI medications in a population 65 years or older enrolled in the Ontario Drug Benefit Program in 2005.

METHODS: Using a retrospective cohort design, dispensings of opioids, laxatives, and acid suppressants were identified using claims reimbursement data. Concurrent dispensings were defined as having at least one "GI medication-dispensed day" overlapping an "opioid-dispensed day".

RESULTS: More than 18 percent of the elderly, drug plan population was dispensed an opioid in 2005. Women had more opioid dispensings and were dispensed opioids for extended periods of time as compared with men. Approximately half of patients with an opioid dispensing were concomitantly dispensed a GI medication; these medications were dispensed nearly twice as frequently among people with chronic opioid dispensings when compared with people with nonchronic opioid dispensings.

CONCLUSIONS: Although laxatives are commonly recommended in patients taking opioids, only half of the older adults in Ontario who were dispensed an opioid also received a concomitant GI medication dispensing. As the elderly are more likely to develop opioid-induced constipation, the prophylactic use of laxatives and/or acid suppressant medications is often necessary to mitigate the side effects associated with their pain management.