Why do we need to implement the ICD- 11? When pain science and practice meet policies

This article first appeared in the European Journal of Pain, Volume 26, Issue 9 p. 2003-2005. It was written by The Societal Impact of Pain Platform (SIP), of which Chronic Pain Ireland was a contributor.

Across the world, chronic pain remains the leading cause of disability linked with negative outcomes in, amongst others, mood, sleep and quality of life, and a significant cost to society. The situation is complicated by the inconsistent global approach in classifying presentations of chronic pain that would allow more accurate data to be collected. Thus, there is a requirement for international agreement on the use of standardized diagnoses and tools.

ICD is an international standard diagnostic tool for epidemiology, health management, research and clinical purposes, as well as the international standard for reporting of diseases and health problems (Treede et al., 2019). ICD can be used to record individual health conditions, to generate and share data on these conditions for a variety of purposes, including research, reimbursement and policy planning (https://icd.who.int/browse11/l-m/en) Barke et al., 2018).

Not recording and reporting diagnoses in a standardized format has significant consequences for people living with pain. It affects their treatments, their life and their social participation on an individual level, but also leads to difficulties for their patient organizations when attempting to make sense of the inconsistent global picture of the condition(s) presented to them. In research, the lack of a systematic classification has also made it impossible to collect accurate epidemiological data at the global level, which impacts on the ability of policy makers and health services to design appropriate policy, services and interventions for those requiring them. In public health policy, receiving accurate and timely information and data on costs, treatments and the societal impact of painful conditions is of paramount importance in order to dictate public health policy and campaigns. (Barke et al., 2018). Additionally, ICD-11 integrates the coding process into electronic health records in a much more efficient manner, if compared to previous versions. In 2017, it was field-tested in 31 countries with more than 112,000 codes. The current version of ICD-11 contains more than 16, 000 unique codes for disease, injuries and causes of death, more than 120, 000 codable terms, and for the first time, it’s entirely electronic. Moreover, of practical importance, recent data suggest a superiority of ICD-11 measures over DSM-5 metrics in predicting disability after pain rehabilitation (Elmose Andersen et al. 2022).

For patients and doctors alike, often the centre of attention is the search for the cause of the pain. The motive is to end the pain by ending its cause. While this is often a fruitful approach, especially in acute pain, for chronic pain things frequently are more difficult. However, regardless of these empirical questions, chronic pain itself is a fact that requires that society, health systems and politics take note of it. The first step in clarifying this issue is to establish common ground regarding the documentation of chronic pain for clinical, budgetary and policy purposes (Rief et al., 2012). With the recognition and inclusion of chronic pain in the ICD-11, a significant step has been taken (Treede et al., 2019). This has major implications in pain science, clinical practice and public health policy.

Regarding policy, the inclusion of chronic painful conditions in ICD-11 will increase the recognition of chronic pain as a health problem and contribute to better access to adequate pain treatment for those suffering from pain around the world. Further, it is to be hoped that the improvement in both recognition and classification will lead to enhanced and focussed research funding from a wider selection of funding bodies when considering the widespread impact of chronic pain. For this reason, the Societal Impact of Pain (SIP) platform recently considered that the implementation of the ICD-11 must be a priority and supports this reflection at European and national levels on the subject (https://www.sip-platform.eu/). Additionally, the SIP platform remains convinced that researchers and clinicians must be informed about the evolution of policies and the impact their activities have had on them, thus ‘closing the loop’.

In 2022, in cooperation with the World Health Organization (WHO), the International Association for the Study of Pain (IASP) has developed a classification based on the latest scientific evidence. Recognizing chronic pain in a systematic classification offers a unique opportunity to improve the diagnosis, treatment, research of pain worldwide and orientate policy initiatives. Thanks to the hierarchical structure of the ICD-11, professionals can use the diagnoses at different levels (from very broad to quite specific). In addition to the absence of disease and infirmity, according to the WHO, physical, mental and social well-being is part of the concept of health. In chronic conditions, especially in chronic pain, patients’ functioning is affected (Barke et al., 2020). Therefore, a biopsychosocial assessment is essential. The International Classification of Functioning, Disability and Health (ICF) is considered, along with the ICD, as the main classifications of the WHO family of international classifications (WHO-FIC) (https://icd.who.int/dev11/l-icf/en). Thus, the combined use of ICD-11 and ICF should improve research on chronic pain through more precise and adequate coding, as well as the management of patients through better diagnostic classification (Hornemann et al., 2020).