Defining Prescription Drug Misuse: A Naturalistic Evaluation of National Survey on Drug Use and Health Data From 2012-2014 to 2015-2017

Abstract

Objectives: Prescription drug misuse (PDM) is a significant public health problem. As research has evolved, the definitions of misuse have varied over time, yet the implications of this variability have not been systematically studied. The objective of this study was to leverage a change in the measurement of PDM in a large population survey to identify its impact on the prevalence and correlates of this behavior.

Methods: Data from the National Survey on Drug Use and Health were compared before and after a change in the definition of PDM from one that restricted the source and motive for use to one that captured any misuse other than directed by a prescriber. Three-year cohorts were constructed, representing a restricted definition of PDM (2012-2014) and a broad definition of PDM (2015-2017).

Results: Segmented logistic regression models indicated a significant increase in PDM prevalence for all 3 drug types examined (opioids, tranquilizers, and sedatives). Although the magnitude of differences varied somewhat based on drug type, the broader definition was generally associated with older age, higher prevalence of health insurance, and higher odds of misusing one's own prescription. Some worsening of mental health indicators was observed, but results indicated few other clinical or substance use differences.

Conclusions: Definitions of prescription drug misuse have a substantial impact on the prevalence of misuse and some impact on the characteristics of the population. Further research is needed to understand the optimal strategy for measuring this behavior, based on the scientific or public health question or interest.

Figure 1.. Prevalene of Prescription Drug Use 2012–2017.

Black filled shapes denote prevelance rates of substance misuse each year of the NSDUH survey from 2012 to 2017. Squares indicate prevelance rates or predicted prevalence rates using the restrictive definition of misuse (i.e., 2012–14 definition). Triangles indicate prevelance rates using the broad definition (i.e., 2015–17 definition). The white filled squares are prevelance rates that have been predicted using parameters from the segmented logistic regressions for each substance respectively. These estimates represent the predicted prevelance rates for each substance for 2015 with the restrictive definition. These estimates represent the predicted 2015 prevelance rates as if there was no definition change. Error bars are two times the standard error to increase visibility. The standard errors for the sedative estimates were too small to be plotted.