ICD-11: Neurocognitive Disorders

Abstract

The section 06 (Mental, Behavioural or Neurodevelopmental Disorders) of the current version Beta Draft (Mortality and Morbidity Statistics, 16.12.2017) of the ICD 11 (International Statistical Classification of Diseases and Related Health Problems) replaces the F0-section of the ICD-10. Several changes, particularly with regard to the classification of neurodegenerative disorders have been introduced. It can be considered a progress that the concept of "organic" syndromes has been dropped and that the section focusses on acquired conditions with cognition as the main area of symptoms. Regarding dementia, the 06 section still uses a syndromal approach of for example dementia due to Alzheimer disease (AD). The development of biomarkers and the molecular concept of AD is not incorporated, yet. In section 08 (Diseases of the Nervous System) Alzheimer disease without reference to symptoms can be classified, however, this section also misses reference to biomarkers, which leaves uncertainty of how the diagnosis should be made.In section 06 the condition of minor neurocognitive disorder was originally only defined as a syndrome without reference to a disease. This has been modified and it is now possible to classify the condition in association with a disease (e. g. AD), however, also without reference to biomarkers.The syndromal approach of section 06 is of value, since in many parts of the world, there is no access to AD biomarkers and all current therapies are tested and in some cases approved for Alzheimer dementia rather than AD as a molecular condition. The lack of any reference to AD biomarkers within ICD-11 so far, however, is a highly relevant limitation with the development of treatments, which target specific components of pathology (e. g. anti-amyloid treatment).