Examining Longitudinal Stimulant Use and Treatment Attendance as Parallel Outcomes in Two Contingency Management Randomized Clinical Trials

Abstract

The primary aim of this study was to examine stimulant use and longitudinal treatment attendance in one ‘parallel outcomes’ model in order to determine how these two outcomes are related to one another during treatment, and to quantify how the intervention impacts these two on- and off-target outcomes differently. Data came from two multi-site randomized clinical trials (RCTs) of contingency management (CM) that targeted stimulant use. We used parallel multilevel modeling to examine the impact of multiple pre-specified covariates, including selected Addiction Severity Index (ASI) scores, age and sex, in addition to CM on concurrent attendance and stimulant use in two separate analyses, i.e., one per trial. In one trial, CM was positively associated with attending treatment throughout the trial (β = 0.060, p < 0.05). In the second trial, CM predicted negative urinalysis (−UA) over the 12-week treatment period (β = 0.069, p < 0.05). In both trials, there was a significant, positive relationship between attendance and −UA submission, but in the first trial a −UA at both baseline and over time was related to attendance over time (r = 0.117; r = 0.013, respectively) and in the second trial, a −UA submission at baseline was associated with increased attendance over time (r = 0.055). These findings indicate that stimulant use and treatment attendance over time are related but distinct outcomes that, when analyzed simultaneously, portray a more informative picture of their predictors and the separate trajectories of each. This ‘indirect reinforcement’ between two clinically meaningful on-target (directly reinforced behavior) and off-target (indirectly reinforced behavior) outcomes is in need of further examination in order to fully exploit the potential clinical benefits that could be realized in substance use disorder treatment trials.

Decreases in smoking during treatment for methamphetamine-use disorders: preliminary evidence

“…Overall, our off-target findings of CM are consistent and of moderate size, which is consistent with other reports of off-target effects of CM. (McDonell et al, 2014; McDonell et al., 2013; McPherson et al, 2016) Moreover, the tobacco smoking outcomes observed in this preliminary study warrant further investigation. Development of novel behavioral and pharmacotherapeutic treatments that support patients with concurrent addiction to nicotine and MA is key given the high prevalence rates.…”

Cardiorespiratory fitness and body composition of stimulant users: A baseline analysis of the STRIDE cohort

“…A second limitation may be the lack of variability in a number of individual variables, particularly stimulant use. Despite recruiting clients in a residential treatment setting, drug use, as determined by the ASI drug subscale score, was nearly half that observed in previous studies with stimulant users (McPherson et al, 2016). Similarly, our population of stimulant users reported a relatively low number of physical illnesses or medical conditions (de la Cruz et al, 2016).…”

A review of contingency management for the treatment of substance-use disorders: adaptation for underserved populations, use of experimental technologies, and personalized optimization strategies

“… 6 It has also been demonstrated that CM indirectly reinforces treatment attendance when attendance is mandatory in order to provide the required urine sample. 65 While these off-target effects are modest and likely insufficient to be considered adequate treatment options on their own, these preliminary findings offer promising pathways for additional development. We discuss this further in our conclusions at the end of this review.…”