Opioid Use Patterns Among Active Duty Service Members and Civilians: 2006–2014
Authors: Kazanis William , Pugh Mary J , Tami Claudina , Maddry Joseph K , Bebarta Vikhyat S , Finley Erin P , McGeary Don D , Carnahan David H , Potter Jennifer S 
Published: January 2018

Abstract

Introduction
Between 2001 and 2009, opioid analgesic prescriptions in the Military Health System quadrupled to 3.8 million. The sheer quantity of opioid analgesics available sets the stage for issues related to misuse, abuse, and diversion. To address this issue, the Department of Defense implemented several directives and clinical guidelines to improve access to appropriate pain care and safe opioid prescribing. Unfortunately, little has been done to characterize changing patterns of opioid use in active duty service members (ADSM), so little is known about how combat operations and military health care policy may have influenced this significant problem. We examined changes in opioid use for ADSM between 2006 and 2014, compared trends with the civilian population, and explored the potential role of military-specific factors in changes in opioid use in the Military Health System.

Materials and Methods
After obtaining Institutional Review Board approval, administrative prescription records (Pharmacy Data Transaction Records) for non-deployed ADSM were used to determine the number of opioid prescriptions dispensed each year and the proportion of ADSM who received at least one prescription per month between 2006 and 2014. Based on the observation and the literature, we identified December 2011 as the demarcation point (the optimal point to identify the downturn in opioid use) and used it to compare opioid use trends before and after. We used an autoregressive forecast model to verify changes in opioid use patterns before and after 2011. Several interrupted time series models examined whether military system-level factors were associated with changes in opioid use.

Results
Between 2006 and 2014, 1,516,979 ADSM filled 7,119,945 opioid prescriptions, either in military treatment facilities or purchased through TRICARE. Both active duty and civilian populations showed signs of decreasing use after 2011, but this change was much more pronounced among ADSM. The forecast model showed a significant difference after 2011 between the projected and actual proportion of ADSM filling an opioid prescription, confirming 2011 as a point of divergence in opioid use. Interrupted time series models showed that the deflection point was associated with significant decreases. A significant increase of 0.261% in opioid prescriptions was seen for every 1,000 wounded in action service members in a given month. Troops returning from Operation Enduring Freedom, Operation Iraqi Freedom, or Operation New Dawn did not appear to influence the rates of use. Even after accounting for returning troops from Operation Enduring Freedom/Operation Iraqi Freedom/Operation New Dawn and wounded in action counts, the deflection point was associated with a lower proportion of ADSM who filled an opioid prescription, leading to a decrease of 1.61% by the end of the observation period (December 2014).

Conclusion
After December 2011, opioid use patterns significantly decreased in both civilian and ADSM populations, but more so in the military population. Many factors, such as numbers of those wounded in action and the structural organization of the Military Health System, may have caused the decline, although more than likely the decrease was influenced by many factors inside and outside of the military, including policy directives and cultural changes.