The ACTTION-American Pain Society Pain Taxonomy (AAPT): An Evidence-Based and Multidimensional Approach to Classifying Chronic Pain Conditions

Abstract

Current approaches to classification of chronic pain conditions suffer from the absence of a systematically implemented and evidence-based taxonomy. Moreover, existing diagnostic approaches typically fail to incorporate available knowledge regarding the biopsychosocial mechanisms contributing to pain conditions. To address these gaps, the Analgesic, Anesthetic, and Addiction Clinical Trial Translations Innovations Opportunities and Networks (ACTTION) public-private partnership with the US Food and Drug Administration and the American Pain Society (APS) have joined together to develop an evidence-based chronic pain classification system called the ACTTION-APS Pain Taxonomy (AAPT). This manuscript describes the outcome of an ACTTION-APS consensus meeting, at which experts agreed on a structure for this new taxonomy of chronic pain conditions. Several major issues around which discussion revolved are presented and summarized, and the structure of the taxonomy is presented. AAPT will include the following Dimensions: 1) Core Diagnostic Criteria, 2) Common Features, 3) Common Medical Comorbidities, 4) Neurobiological, Psychosocial and Functional Consequences, and 5) Putative Neurobiological and Psychosocial Mechanisms, Risk Factors & Protective Factors. In coming months, expert working groups will apply this taxonomy to clusters of chronic pain conditions, thereby developing a set of diagnostic criteria that have been consistently and systematically implemented across nearly all common chronic pain conditions. It is anticipated that the availability of this evidence-based and mechanistic approach to pain classification will be of substantial benefit to chronic pain research and treatment. Perspective The ACTTION-APS Pain Taxonomy is an evidence-based chronic pain classification system designed to classify chronic pain along the following Dimensions: 1) Core Diagnostic Criteria, 2) Common Features, 3) Common Medical Comorbidities, 4) Neurobiological, Psychosocial and Functional Consequences, and 5) Putative Neurobiological and Psychosocial Mechanisms, Risk Factors & Protective Factors.

“Unsettling circularity”: Clinical trial enrichment and the evidentiary politics of chronic pain

“…The IMMPACT and ACTTION initiatives frame their mission explicitly as working toward the development of evidence-based clinical trial practice for pain therapeutics (Dworkin et al, 2011b;Fillingim et al, 2014). It is thus important to recognize that the current promotion of EERW is framed not solely in terms of cost containment and the streamlining of regulatory approval, but as part of a larger movement toward standardization and coordination of research.…”

“…Researchers remain dependent on subjective patient self-reporting for pain measurement and even standardized methods for the clinical evaluation of pain rely on patient-reported numerical variables, facial expression scales or qualitative descriptions that range from "no pain at all" to "worst pain imaginable" (Hewitt et al, 2011). A significant portion of IMMPACT's and ACTTION's publications have been devoted to rationalizing and standardizing measurement, rating scales and outcomes in pain trials (Turk et al, 2003;Dworkin et al, 2005b;Turk et al, 2006;Farrar et al, 2014;Fillingim et al, 2014;Smith et al, 2015). Even as the burgeoning sciences of biomarkers and genomics have invigorated the search for a mechanism-based understanding of chronic pain (Kim et al, 2009;Diatchenko et al, 2013), pain scientists recognize that the fruits of such inquiry will still need to be coordinated with, rather than superordinate to, environmental and psychosocial aspects of the pain experience (Borsook and Kalso, 2013;Fillingim et al, 2014).…”

“…A significant portion of IMMPACT's and ACTTION's publications have been devoted to rationalizing and standardizing measurement, rating scales and outcomes in pain trials (Turk et al, 2003;Dworkin et al, 2005b;Turk et al, 2006;Farrar et al, 2014;Fillingim et al, 2014;Smith et al, 2015). Even as the burgeoning sciences of biomarkers and genomics have invigorated the search for a mechanism-based understanding of chronic pain (Kim et al, 2009;Diatchenko et al, 2013), pain scientists recognize that the fruits of such inquiry will still need to be coordinated with, rather than superordinate to, environmental and psychosocial aspects of the pain experience (Borsook and Kalso, 2013;Fillingim et al, 2014). While the fundamentally subjective nature of pain presents challenges for clinicians and researchers alike, it also opens up a space for critique of conventional clinical trial designs that require reliable, uncontroversial metrics of drug efficacy (Tousignant, 2011).…”

Multidimensional Approach to Classifying Chronic Pain Conditions—Less Is More

“…To the Editor: Our team received with enthusiasm the proposal from the ACTTION-APS Pain Taxonomy (AAPT), 1 which claims an evidence-based and multidimensional approach to classifying chronic pain conditions. Attempting to approach an ideal diagnostic system that aims to systematize, organize, and standardize the biopsychosocial assessment of chronic pain patients, a 5-dimension taxonomy was proposed.…”

“…This perspective drew inspiration from the Diagnostic and Statistical Manual of Mental Disorders (DSM), Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), and International Classification of Headache Disorders diagnostic systems. 1 Of these, the DSM is probably the most widely used system in multidisciplinary settings and an essential requirement in the care of pain patients. The evolution of the taxonomies is both necessary and inherent to the progress of science, which develops together with patients', clinicians', researchers', and third-party payers' needs.…”