Factors Associated With Opioid Use in Long-term Cancer Survivors.

PURPOSE: To evaluate factors associated with opioid use in patients with cancer surviving more than five years without recurrence. We evaluated exposures of opioid use before cancer diagnosis, opioid use between cancer diagnosis and five-year anniversary, surgeries, and chemotherapy. METHODS: We conducted a retrospective cohort study using linked provincial administrative data. Patients were aged 24-70 years and eligible for government-funded pharmacare. The index date was the five-year anniversary from diagnosis. Patients were accrued between 2010 and 2015. The main outcome was opioid prescription rate after index date. The main exposures were opioid use before diagnosis, opioid use between diagnosis and index, surgeries, and chemotherapy. A negative binomial regression model was used to estimate relative rates (RR) of opioid use after index date. RESULTS: Our cohort included 7431 individuals. The overall crude prescription rate after the index date was 2 per person-year. The factor most strongly associated with a higher rate of opioid use after index was continuous opioid use between diagnosis and index (RR 46.1, 95% confidence interval 34.8-61.2). Opioid use before diagnosis was also a factor (RR = 1.8, 95% confidence interval 1.44-2.19). A history of depression, comorbidity, and more than two years of diabetes were also associated with higher risk of post-index date opioid use. Significant interactions were identified between prior opioid use and opioid use between diagnosis and index. Most prescriptions are from family physicians. CONCLUSION: Patients who use opioids continuously between diagnosis and index date are at increased risk of continued use after five years of survival. Safe and appropriate pain management is an important survivorship issue.

Comparison of Opioid Prescribing Among Cancer and Noncancer Patients Aged 18-64: Analysis Using Administrative Data.

BACKGROUND: Opioid prescribing has been increasingly scrutinized among noncancer patients. As an unintended consequence, opioids may be underprescribed for cancer patients. The purpose of this study was to compare trends in opioid prescribing in younger adults with and without cancer. METHODS: From 2004 to 2013, Ontario residents aged 18-64 years eligible for government paid pharmacare were annually stratified into three groups: no cancer history, cancer diagnosis more than five years ago, and cancer diagnosis five years ago and less. We evaluated time trends in two annual outcomes: opioid prescription rate and mean daily opioid dose. RESULTS: In 2013, 800,371 individuals were eligible for this study (3% with recent cancer and 2% with remote cancer). Across all years, compared with noncancer patients, overall opioid prescription rates were 43% and 26% higher for those with recent and remote cancer, respectively. Overall, a 1% relative annual increase was seen in those without cancer and a 1% decrease was seen in those with a recent cancer. Changes in prescription rates varied with drug class and cancer group. Notably, long-acting opioids had a relative annual increase of 7% in noncancer patients vs. 2% in recent cancer patients. Immediate-release combination agents had a relative annual decrease of 2% for all cancer groups. Trends in mean daily dose were similar between groups, but by 2013, they were lowest in recent cancer patients, regardless of drug class. INTERPRETATION: Secular trends in opioid prescribing affect cancer and noncancer patients similarly. Further research is required to assess the potential impact on symptom management.

Opioid Prescribing Among Cancer and Non-cancer Patients: Time Trend Analysis in the Elderly Using Administrative Data.

CONTEXT: 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 years were identified from 2004 to 2013. Subjects were annually stratified into three 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. CONCLUSION: Overall prescribing rates for cancer patients aged ≥65 years 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.