How Treatment-Refractory Addiction Is Defined: A Scoping Review

The addiction field lacks consensus terminology for individuals who utilize multiple treatments but do not enter remission. This scoping review evaluates how this concept is defined across the literature.

A comprehensive search was conducted on September 16, 2024, by a medical librarian. Included articles presented new data in adult substance-using populations described as treatment-resistant or treatment-refractory. Articles were excluded if they lacked a clear definition, if the population assessed was dual diagnosis-focused, or if individuals did not want to engage in care (ie, resisting).

In total, 1834 and 379 articles were reviewed at the abstract and full-text levels, respectively, with 39 meeting inclusion criteria. Treatment-resistant (n=23) and treatment-refractory (n=11) were the most used terms. Alcohol (n=10) and opioid (n=27) use cohorts were most commonly assessed. Six studies occurred in deep brain stimulation cohorts. Themes of severity of use, treatment history with ongoing use, and psychosocial or functional impairments overlapped definitions; however, they varied widely in specificity. The most comprehensive definitions incorporated thresholds for amount/frequency consumed, duration of addiction or age of onset, number of treatment encounters, treatment duration, and a pharmacological treatment trial.

The lack of a consistent definition for continued treatment nonresponse poses challenges for research and clinical care. The use of "treatment-refractory" over "treatment-resistant" may better align with person-first language, emphasizing the multifaceted nature of addiction rather than implying something about the individual. An agreed-upon definition may improve the identification of this resource-intensive and at-risk population, guiding the development of tailored interventions that better address their treatment needs.