Opioid use in cancer patients compared with non-cancer pain patients in a veterans population.

BACKGROUND: Opioid safety initiatives may secondarily impact opioid prescribing and pain outcomes for cancer care.

METHODS: We reviewed electronic health record data at a tertiary Veterans Affairs system (VA Palo Alto) for all patients from 2015-2021. We collected outpatient Schedule II opioid prescriptions data and calculated morphine milligram equivalents (MMEs) using CDC conversion formulas. To determine the clinical impact of changes in opioid prescription, we used the highest level of pain reported by each patient on the 0 to 10 Numeric Rating Scale (NRS) in each year, categorized into mild (0-3), moderate (4-6), and severe (7 and above).

RESULTS: Among 89,569 patients, 9073 had a cancer diagnosis. Cancer patients were almost twice as likely to have an opioid prescription compared with non-cancer patients (69.0% vs 36.7%, respectively). The proportion of patients who received an opioid prescription decreased from 27.1% to 18.1% (trend p < .01) in cancer patients, and from 17.0% to 10.2% in non-cancer patients (trend p < .01). Cancer and non-cancer patients had similar declines of MMEs per year between 2015 and 2019, but the decline was more rapid for cancer patients (1462.5 to 946.4, 35.3%) compared to non-cancer patients (1315.6 to 927.7, 29.5%) from 2019-2021. During the study period, the proportion of non-cancer patients who experienced severe pain was almost unchanged, while it increased among cancer patients, reaching a significantly higher rate than among non-cancer patients in 2021 (31.9% vs 27.4%, p < .01).

CONCLUSIONS: Our findings suggest potential unintended consequences for cancer care due to efforts to manage opioid-related risks.