2017 HSR&D/QUERI National Conference

4006 — Trends in Opioid and Nonsteroidal Anti-inflammatory Drug Prescriptions and Adverse Events before and after an Opioid Safety Initiative in Veterans

Lead/Presenter: Sherrie Aspinall, COIN - Pittsburgh/Philadelphia
All Authors: Fassio V (Kansas City VA Medical Center) Aspinall SL (VA Center for Medication Safety and Center for Health Equity Research and Promotion) Zhao X (VA Center for Health Equity Research and Promotion) Miller DR (VA Center for Healthcare Organization and Implementation Research) Singh JA (Birmingham VA Medical Center) Good CB (VA Center for Medication Safety and Center for Health Equity Research and Promotion) Cunningham FE (VA Center for Medication Safety)

Objectives:
The Veterans Health Administration (VHA) implemented an opioid safety initiative (OSI) to reduce high-risk opioid prescribing. Prescribing of alternative medications, such as non-steroidal anti-inflammatory drugs (NSAIDs), may have increased after the OSI and led to use in populations at increased risk of NSAID-related adverse effects. Therefore, the objectives are to describe the prevalence and incidence of opioid and NSAID use before and since the start of the OSI and to assess the rates of adverse events among opioid and NSAID users.

Methods:
This retrospective cohort study included 3,315,846 outpatients who were regular users of VHA and had at least one opioid and/or NSAID prescription between fiscal years (FYs) 2011 and 2015. The OSI began in August 2012 and was fully implemented across VHA by the end of FY2013. Therefore, the study timeframe was categorized into baseline (FY2011-2012), transition (FY2013), and post-implementation (FY2014-2015) phases. The outcomes measures were prevalence and incidence of opioid and NSAID use and rates of NSAID-related adverse events among incident opioid and NSAID users. For adverse events, Cox proportional hazards models with inverse probability weighting were used to adjust for potential selection bias and confounding.

Results:
Quarterly opioid prevalence rates were approximately 21% during the baseline and transition phases, and then decreased in the post-implementation phase to 17.3%. NSAID prevalence rates remained constant at about 16%. Opioid incidence rates gradually decreased (2.7% to 2.2%) during the study, while NSAID incidence rates remained around 2.2%. After inverse probability weighting, patients receiving opioids had a greater risk of cardiovascular events (hazard ratio [HR] 1.38; 95% CI 1.33-1.44), acute kidney injury (HR 2.55; 95% CI 2.47-2.64), gastrointestinal bleeding (HR 1.70; 95% CI 1.58-1.84), and all-cause mortality (HR 3.72; 95% CI 3.59-3.86) than NSAID users.

Implications:
The prevalence and incidence of opioid use declined following implementation of the OSI, while NSAID use remained constant. Adverse events were higher among opioid users.

Impacts:
The findings provide additional support for ongoing efforts to use non-opioid strategies for pain management when appropriate. Further research is needed to examine the greater incidence of serious adverse outcomes, and cause of death, with opioids.