The International Classification of Diseases (ICD) published by the World Health Organization (WHO) is used to help “organise” medical conditions. However, chronic pain conditions have always played the “poor relations” to other medical conditions. While these classification systems reflect the developments in pain research over the last 2 decades, and they do not have clear treatment or management implications. The new the ICD-11 provided a new diagnosis of Chronic Primary Pain (CPP) and Dr. Hegarty welcomes this positive step.
To overcome the shortcomings identified in previous and current versions of both DSM and ICD, the new classification system, the ICD-11 provided a new diagnosis of Chronic Primary Pain (CPP). This can now be used independent of identified biological or psychological contributors unless another diagnosis would better account for the presenting symptoms. The goal was to create a classification that will be useful in both primary care and in specialized pain management settings.
The new ICD-11 CPP classification is also expected to enhance pain management outcomes, in that it allows for inferences about unknown aspects of an individual who has been assigned a specific pain category.
Dr. Dominic Hegarty (Clinical Director Pain Relief Ireland) says “The new ICD-11 CPP classification is also expected to enhance pain management outcomes, in that it allows for inferences about unknown aspects of an individual who has been assigned a specific pain category. Indeed, given a pain (sub)category, clinicians and researchers can infer likely causes of symptoms, predict most likely consequences, estimate a timeline, the most likely future developments, and optimize treatment plans for that person”.
By including a distinct CPP syndrome classification within the ICD-11, it is hoped to avoid the problems associated with previous classifications of chronic pain when the etiology is unclear, but the emotional distress and functional disability associated with such pain are very evident, as the Global Burden of Disease project has reported. The availability of 6 classes of chronic secondary pain syndromes in the same classification will facilitate the distinction of pain as a disease or long-term condition from pain as a symptom, as already demonstrated in a pilot field trial.
This classification has clear treatment and management implications: a multimodal approach that addresses the contributing psychological, social, and biological contributors is expected to lead to better outcomes for patients with CPP diagnoses of at least moderate severity, relative to unimodal interventions alone. In chronic secondary pain syndromes, there will be additional disease-specific treatment options to be considered as well. In addition, the representation of CPP in health statistics is expected to advance public policy and research.
Figure shows the overview of the subgroup of Chronic Primary Pain (ICD-11)(Modified from Nicholas et al. Pain 160 (2019) 28–37 2019)