04 - Other ICD 11 chapters relevant to diagnostic

Other ICD-11 chapters relevant to diagnostic formulation of mental, behavioural and neurodevelopment

27 Using the CDDR for ICD-11 mental, behavioural and neurodevelopmental disorders in clinical settings to be exhaustive. For example, the grouping elimination disorders contains enuresis, encopresis and elimination disorder, unspecified; the other specified residual has been suppressed for this grouping and thus does not appear in the MMS. The CDDR include essential (required) features for other specified categories at the grouping level (e.g. other specified mood disorder, other specified dissociative disorder). A particular other specified diagnosis should be applied when the presentation is judged to be a clinically significant mental disorder falling within a particular grouping of disorders (e.g. mood disorders, dissociative disorders) because it shares primary clinical features with these disorders but does not fulfil the diagnostic requirements of any of the other available categories. For example, a presentation that included all of the essential features of schizophrenia but had not met the 1-month duration requirement would appropriately be diagnosed as other specified primary psychotic disorder. A presentation characterized by abnormal eating or feeding behaviours that did not correspond to the essential features of any of the specific feeding and eating disorders categories but resulted in significant risk or damage to health, significant distress or significant impairment in functioning could be diagnosed as other specified feeding and eating disorder. Sometimes, other specified diagnoses may refer to recognizable syndromes that have not been included as separate categories in ICD-11 – for example, because they are very rare or are not sufficiently widely recognized as disorders. Ganser syndrome, for example, would be diagnosed as other specified dissociative disorder, and what is sometimes called “pathological demand avoidance” could be diagnosed as other specified disruptive behaviour or dissocial disorder if it did not meet the diagnostic requirements for oppositional defiant disorder. The characteristics of the presentation in other specified disorder should be specified in the clinical record. Unspecified categories are most commonly used by professional coders when the clinician has provided insufficient information in the clinical record to assign a more specific diagnosis. In clinical situations, unspecified categories are appropriate only when insufficient information is available to make a more definitive diagnosis and, if possible, should be changed when additional information becomes available. In contrast to other specified categories, which are used when the clinician knows what the disorder is but there is no precisely corresponding code, unspecified categories are used when the clinician has been unable to arrive at a precise diagnostic determination. For example, an individual presenting in a hospital emergency department who is exhibiting hallucinations and delusions in the absence of evidence of substance use, delirium or dementia might be assigned a diagnosis of schizophrenia or other primary psychotic disorder, unspecified, until a more complete assessment can be conducted. Unspecified categories should not be used as an administrative shortcut when a more specific diagnosis can be assigned; this results in a major loss of clinical and statistical information. Other ICD-11 chapters relevant to diagnostic formulation of mental, behavioural and neurodevelopmental disorders Categories from any of the other 24 chapters in ICD-11 may be comorbid with a mental, behavioural or neurodevelopmental disorder, and thus relevant to their diagnostic formulation. However, the following chapters warrant particular attention: Chapter 7. Sleep-wake disorders The ICD-11 chapter on sleep-wake disorders brings together ICD-10 nonorganic sleep disorders (F51) with “organic” sleep disorders (G47) that were classified in the ICD-10 chapter on diseases of the nervous system, as well as categories previously included in several other chapters (i.e. endocrine, nutritional and metabolic diseases; diseases of the respiratory system; certain

Clinical Descriptions and Diagnostic Requirements for ICD-11 Mental, Behavioural or Neurodevelopmental Disorders conditions originating in the perinatal period). Sleep-wake disorders previously included in the ICD-10 chapter on mental and behavioural disorders include nightmare disorder, sleepwalking disorder, sleep terrors and “nonorganic” versions of insomnia disorders, hypersomnia disorders and circadian rhythm sleep-wake disorders (disorders of the sleep-wake schedule in ICD-10). The unified ICD-11 chapter on sleep-wake disorders reflects the fact that the pathophysiology of most of these disorders is complex and includes both physiological and psychological/ behavioural components. ICD-11 abandons outdated and incorrect assumptions about the etiology of sleep-wake disorders – in particular, the obsolete distinction between “organic” and “nonorganic” disorders. The chapter is intended to enhance patient care and public health by creating a more visible and accurate system that will enhance clinician awareness and improve diagnostic accuracy and treatment. Placement of these conditions in a separate chapter on sleepwake disorders is in no way intended to indicate that they should not be diagnosed and treated by appropriately trained mental health professionals. Chapter 8. Diseases of the nervous system Diseases of the nervous system have a close relationship with mental, behavioural and neurodevelopmental disorders. Disorders in both chapters may affect cognition, emotional regulation or behaviour, and reflect dysfunctions in the psychological, biological or developmental processes. Given that mental, behavioural and neurodevelopmental disorders also affect the brain, in some instances the distinction between the two chapters is arbitrary and reflects professional tradition – especially the boundary between psychiatry and neurology – as much as biological or phenomenological differences between the conditions listed in each. For some conditions, the psychological, behavioural or developmental syndrome is classified in the mental, behavioural and neurodevelopmental disorders chapter, while the underlying etiology may be classified in diseases of the nervous system. This includes disorders of intellectual development, autism spectrum disorder and stereotyped movement disorder in the neurodevelopmental disorders grouping; and delirium, mild neurocognitive disorder, amnestic disorder and dementia in the neurocognitive disorders grouping, all of which are diagnosed regardless of etiology. If the etiology is known, the corresponding diagnosis should also be assigned, which is often but not always in in the chapter on diseases of the nervous system. The other neurodevelopmental disorders (e.g. developmental learning disorder, developmental speech or language disorder, developmental motor coordination disorder) are generally not diagnosed if the symptoms are fully accounted for by a disease of the nervous system. When mental, behavioural or neurodevelopmental syndromes are judged to be a direct pathological consequence of a disease of the nervous system and are a specific focus of clinical attention, a diagnosis from the grouping secondary mental or behavioural syndromes associated with disorders and diseases classified elsewhere may be assigned. For example, a psychotic syndrome with prominent visual hallucinations that is judged to be the direct pathophysiological consequence of Parkinson disease would be diagnosed as secondary psychotic syndrome, with hallucinations along with a diagnosis of Parkinson disease. Tic disorders and acquired aphasia with epilepsy (Landau-Kleffner syndrome) were classified in ICD-10 as emotional disorders with onset usually occurring in childhood and adolescence, but in ICD-11 have been moved to the chapter on diseases of the nervous system. In addition, movement disorders caused by medications (e.g. drug-induced parkinsonism, drug-induced dystonia), which are associated with certain medications commonly used to treat mental disorders, are included among the diseases of the nervous system.

29 Using the CDDR for ICD-11 mental, behavioural and neurodevelopmental disorders in clinical settings Chapter 16. Diseases of the genitourinary system This chapter includes a grouping of premenstrual disturbances that may include significant mood symptoms, such as depressed mood and irritability, as well as somatic and cognitive symptoms that may also occur in mood disorders. In particular, premenstrual dysphoric disorder is secondary-parented in the mood disorders grouping of ICD-11, and the CDDR for this entity are provided in this volume. In addition, while nearly all sexual dysfunctions classified as diseases of the genitourinary system in ICD-10 have been moved to the new ICD-11 chapter on conditions related to sexual health (see the next section), pain syndromes that are more generally associated with genital organs or the menstrual cycle are classified in Chapter 16. Chapter 17. Conditions related to sexual health Analogously to sleep-wake disorders, the ICD-10 classification of sexual dysfunctions was based on a Cartesian separation of “organic” and “nonorganic” conditions. Sexual dysfunctions not caused by organic disorder or disease (F52), which also include “nonorganic” versions of the sexual pain disorders vaginismus and dyspareunia, were classified in the ICD-10 chapter on mental and behavioural disorders, and most “organic” sexual dysfunctions are classified in the chapter on diseases of the genitourinary system. These have been brought together in a new unified classification of sexual dysfunctions and sexual pain disorders in the ICD-11 chapter on conditions related to sexual health. This approach is consistent with current, more integrative clinical approaches in sexual health, and recognizes the large body of evidence that the origin and maintenance of sexual dysfunctions and sexual pain disorders most often involves the interaction of physiological and psychological/behavioural factors. Reformulated versions of all sexual dysfunctions from the ICD-10 mental and behavioural disorders chapter can be found in the ICD-11 chapter on conditions related to sexual health, except for ICD-10 excessive sexual drive – a condition most closely related to compulsive sexual behaviour disorder in ICD-11 – which is included in the grouping of impulse control disorders. As with sleep-wake disorders, placement of these conditions in a separate chapter on conditions related to sexual health is not intended to indicate that they should not be diagnosed and treated by appropriately trained mental health professionals. The ICD-11 chapter on conditions related to sexual health also includes gender incongruence, which represents a reformulation and renaming of ICD-10 gender identity disorders. There was substantial evidence that the nexus of stigmatization of transgender people and of mental disorders had contributed to a doubly burdensome situation for transgender and gender-variant people, and that stigma associated with the intersection of transgender status and mental disorders had contributed to precarious legal status, human rights violations and barriers to appropriate health care in this population. Although gender identity is clearly distinct from sex, this chapter appeared to offer the most broadly acceptable home for categories related to gender identity, while making it clear that they are no longer considered to be mental disorders. This position has been supported by a series of ICD-11 field studies. Gender incongruence was not proposed for elimination in ICD-11 because in many countries access to relevant health services is contingent on a qualifying diagnosis. Chapter 21. Symptoms, signs or clinical findings, not elsewhere classified The categories in this chapter are not considered to be disorders but rather provide descriptions of specific symptoms that may be used to describe the reason for a clinical encounter when a more precise diagnosis has not been established for various reasons. These categories may also be used to describe clinically important aspects of the individual’s presentation when a diagnosis has been assigned.