Opioid prescribing among cancer and non-cancer patients: time trend analysis in the elderly using administrative data

Background — In 2007, Cancer Care Ontario introduced a provincial symptom screening program, which included pain, for cancer patients. Over this same time, opioid prescribing has been increasingly scrutinized among non-cancer patients. The study purpose was to see if opioid prescribing changed among older adults after 2007 in the context of changing opioid regulations, and whether effects were different among patients with a cancer history.

Methods — Ontario residents aged ≥65 were identified from 2004 to 2013. Subjects were annually stratified into 3 groups: no cancer history, cancer diagnosis >5 years ago and cancer diagnosis ≤5 years ago. We evaluated time trends by year for: (1) opioid prescription rate, comparing trends before and after 2007, and (2) mean daily opioid dose.

Results — Between 2004 and 2013, opioid prescribing was relatively constant for cancer patients with no observed change in trends after 2007. For non-cancer patients there was a 2% relative annual increase during this period. Significant changes were seen for opioid sub-classes (e.g. decreasing use of long-acting oxycodone). These were similar for those with or without a history of cancer. Among all groups, changes in the mean daily dose over time were similar in all drug classes.

Interpretation — Overall prescribing rates for cancer patients aged ≥65 remain unchanged over time, in spite of the introduction of a provincial symptom screening program. Decreasing prescription rates in some drug sub-classes were observed. The potential impact of these changes on the quality of symptom control for cancer patients needs further investigation.