Study Suggests Link between Length of Prescription for Initial Exposure to Opioids and Long-Term Use
BACKGROUND:
Opioid prescribing has changed in the United States in recent years, peaking in 2012. Since then, the incidence of new long-term opioid use has decreased in the VA healthcare system. This decrease reflects changes in attitudes about and policies governing opioid use in general, and long-term opioid use in particular. However, further investigation is needed to better understand the pathways to long-term opioid prescribing. Therefore, this study examined the association between initial opioid exposure and subsequent long-term use in two national VA cohorts from 2011 and 2016. Using VA data, investigators identified incident opioid users during 2016 (n=317,367 Veterans). Incident use was defined as the first prescription for a non-injectable dosage form of a schedule II opioid, tramadol, or codeine during this period, which was preceded by 365 days with no prescriptions for any of these medications. A secondary cohort was constructed for incident opioid users during 2011 (n=376,140). Investigators examined the relationships between days' supply, daily dose, and number of fills within the first 30 days and subsequent long-term opioid use.
FINDINGS:
- There is a strong relationship between initial opioid exposure and the future likelihood for long-term use. Cumulative days' supply of prescription opioids emerged as the strongest predictor of long-term opioid use, which occurred in only 2% of Veterans dispensed ≤7 days' supply, and in 28% of patients dispensed >30 days' supply.
- Comparing 2011 and 2016 data, the association between day's supply and long-term use persisted, even as the overall rate of long-term opioid use decreased.
IMPLICATIONS:
- These findings suggest that limiting initial opioid exposure may reduce risk for long-term opioid use. Moreover, examination of early opioid exposure may offer an opportunity to recognize when a patient is in the process of starting long-term opioid use.
LIMITATIONS:
- VA administrative data do not include any outside prescriptions or illegal obtainment of opioids.
- Examining prescriptions is not a guarantee that patients took medications as prescribed.
AUTHOR/FUNDING INFORMATION:
This study was funded through HSR&D. All authors are part of HSR&D's Center for Comprehensive Access and Delivery Research and Evaluation (CADRE), Iowa City, Iowa.
Hadlandsmyth K, Lund B, and Mosher H. Associations between Initial Opioid Exposure and the Likelihood for Long-Term Use. Journal of the American Pharmacists Association. November 5, 2018;epub ahead of print.
