208 - 6D72 Amnestic disorder

6D72 Amnestic disorder

Clinical Descriptions and Diagnostic Requirements for ICD-11 Mental, Behavioural or Neurodevelopmental Disorders Amnestic disorder Amnestic disorder includes the following subcategories: 6D72.0 Amnestic disorder due to diseases classified elsewhere 6D72.1 Amnestic disorder due to psychoactive substances, including medications

6D72.10 Amnestic disorder due to use of alcohol

6D72.11 Amnestic disorder due to use of sedatives, hypnotics or

anxiolytics

6D72.12 Amnestic disorder due to other specific psychoactive

substances, including medications 6D72.13 Amnestic disorder due to use of volatile inhalants 6D72.Y Amnestic disorder, other specified cause 6D72.Z Amnestic disorder, unknown or unspecified cause. General diagnostic requirements for amnestic disorder Essential (required) features • Prominent memory impairment relative to expectations for age and general level of premorbid neurocognitive functioning, in the absence of other significant neurocognitive impairment, is required for diagnosis. • The memory impairment represents a marked decline from previous levels of functioning. • The memory impairment is characterized by reduced ability to acquire, learn and/or retain new information. • Evidence of memory impairment is based on: • information obtained from the individual, an informant or clinical observation; • substantial impairment in memory performance as demonstrated by standardized neuropsychological/cognitive testing or, in its absence, another quantified clinical assessment. • The symptoms are not better accounted for by disturbance of consciousness, altered mental status, transient global amnesia (i.e. memory impairment lasting no more than 48 hours, with most cases resolving within 6 hours), delirium, dementia, substance intoxication, substance withdrawal or another mental disorder (e.g. schizophrenia or another primary psychotic disorder, a mood disorder, post-traumatic stress disorder, a dissociative disorder). • The symptoms result in significant impairment in personal, family, social, educational, occupational or other important areas of functioning. In mild cases, if functioning is maintained, it is only through significant additional effort (e.g. compensatory strategies). 6D72 Neurocognitive disorders | Amnestic disorder

613 Neurocognitive disorders Note: when amnestic disorder is due to a disease, condition or injury classified elsewhere (including disorders due to substance use), the diagnostic code corresponding to that disease, condition or injury should assigned along with amnestic disorder. When the etiological condition is unknown, the diagnosis 8A2Z Disorders with neurocognitive impairment as a major feature, unspecified, may be assigned in addition to amnestic disorder. Additional clinical features • Amnestic disorder may or may not include the inability to recall previously learned information. Recent memory is typically more impaired than remote memory, and the ability to recall a limited amount of information immediately is usually relatively preserved. • Standardized neuropsychological/cognitive testing or quantified clinical assessment may be needed to determine the magnitude and pattern of other neurocognitive impairments, and to differentiate amnestic disorder from other neurocognitive disorders (e.g. dementia). • Subjective reports by the affected individual of impairments in learning, memory or recall do not always correspond to objective or measurable impairment in these areas because of potential alteration in the individual’s awareness, misperceptions of abilities, or misattribution of the cause/source of symptoms or problems. Similarly, it is possible that individuals with altered awareness of deficits may not acknowledge or report memory impairments that are present. • If standardized neuropsychological/cognitive testing or quantified clinical assessment is not available, the symptom code MB21.1Z Amnesia, unspecified, may be used provisionally until a quantified assessment can be conducted. Boundary with normality (threshold) • Normal ageing is typically associated with some degree of memory change. A diagnosis of amnestic disorder does not apply if performance is consistent with expectations for the individual’s age, based on age-related norms for performance on standardized assessment. • When memory difficulties consistent with normal ageing are present and clinically relevant, the symptom code MB21.0 Age-associated cognitive decline may be used. Course features • Onset of symptoms can be sudden (e.g. when due to stroke or trauma) or gradual (e.g. when due to psychoactive substances or nutritional deficiencies). Neurocognitive disorders | Amnestic disorder

Clinical Descriptions and Diagnostic Requirements for ICD-11 Mental, Behavioural or Neurodevelopmental Disorders • Symptoms may be relatively stable over time or progressive, depending on the underlying causal condition or etiology. In some cases, symptoms may improve over time, depending on the specific etiology and available treatment options. • When memory impairment worsens progressively over time (e.g. due to an underlying disease of the nervous system), amnestic disorder may represent a prodrome for dementia. Culture-related features • Performance during clinical assessment may vary according to cultural and/or linguistic factors. When assessing impairment in neurocognitive functioning and activities of daily living, cultural and linguistic factors should be considered and accounted for when possible. • When standardized neuropsychological/cognitive testing is utilized for determination of neurocognitive impairment, performance should be measured with appropriately normed, standardized tests. In situations where appropriately normed and standardized tests are not available, assessment of neurocognitive functioning requires greater reliance on clinical judgement. (See the section on general cultural considerations for neurocognitive disorders above for additional information and examples.) Boundaries with other disorders and conditions (differential diagnosis) Boundary with delirium Although delirium often includes memory impairment, it is differentiated from amnestic disorder by the presence of disturbances in attention, orientation and awareness, and significant confusion or global neurocognitive impairment, in contrast to the specific and prominent memory impairment seen in amnestic disorder. Boundary with mild neurocognitive disorder Unlike amnestic disorder, mild neurocognitive disorder is characterized by a mild level of neurocognitive decline, with little or no impairment in functioning of everyday skills and tasks. In mild neurocognitive disorder, symptoms are not typically restricted to memory impairment. Boundary with dementia Amnestic disorder is characterized by prominent memory impairment relative to expectations for age and general level of premorbid neurocognitive functioning, in the absence of other significant neurocognitive impairment. In contrast, dementia is characterized by impairment in two or more cognitive domains, which frequently but not always include memory. Boundary with dissociative amnesia Amnestic disorder is characterized by selective and prominent impairment in the ability to learn and remember new information, usually with relative sparing of memory for previously learned Neurocognitive disorders | Amnestic disorder

615 Neurocognitive disorders information and past events and experiences. In contrast, dissociative amnesia is characterized by inability to recall important autobiographical memories – typically of recent traumatic or stressful events – that is inconsistent with ordinary forgetting, and is often preceded by an emotional stressor, conflict or trauma. Boundary with memory symptoms in other mental disorders Memory impairment may be a presenting feature other mental disorders (e.g. schizophrenia, mood disorders, post-traumatic stress disorder, dissociative disorders). If the memory impairment is better explained by another mental disorder, an additional diagnosis of amnestic disorder should not be assigned. Boundary with transient global amnesia In transient global amnesia the memory impairment is temporary (i.e. lasting no longer than 48 hours, with most cases resolving within 6 hours) whereas in amnestic disorder memory impairment is persistent, although in some cases it may improve with treatment, depending on the etiology. Amnestic disorder due to diseases classified elsewhere Essential (required) features • All diagnostic requirements for amnestic disorder are met. • There is evidence from history, physical examination or laboratory findings that symptoms are caused by the direct physiological consequences of a medical condition (e.g. a disease of the nervous system, a traumatic brain injury, an infection, a tumour, another disease process affecting areas of the brain involved in memory). This judgement depends on establishing the following. • The medical condition is known to be capable of producing memory impairment. • The course of the memory impairment (e.g. onset, trajectory of symptoms, response to treatment) is consistent with causation by the medical condition. Note: when amnestic disorder is due to a disease, condition or injury classified elsewhere (including disorders due to substance use), the diagnostic code corresponding to that disease, condition or injury should assigned along with amnestic disorder. When the etiological condition is unknown, the diagnosis 8A2Z Disorders with neurocognitive impairment as a major feature, unspecified, may be assigned in addition to amnestic disorder. Potentially explanatory medical conditions (examples) • Anaemias or other erythrocyte disorders • Certain infectious or parasitic diseases (e.g. meningitis) • Diseases of the nervous system (e.g. cerebral ischaemic stroke, cerebral palsy, epilepsy or seizures, hypoxic-ischaemic encephalopathy) Neurocognitive disorders | Amnestic disorder 6D72.0

Clinical Descriptions and Diagnostic Requirements for ICD-11 Mental, Behavioural or Neurodevelopmental Disorders • Endocrine diseases (e.g. hypothyroidism) • Intracranial injury • Metabolic disorders (e.g. hypo-osmolality or hyponatraemia) • Neoplasms of the brain or central nervous system • Nutritional disorders (e.g. vitamin B1 or B12 deficiency) Amnestic disorder due to psychoactive substances, including medications Essential (required) features • All diagnostic requirements for amnestic disorder are met. • There is evidence from history, physical examination or laboratory findings that the disturbance is caused by the direct physiological consequences of use of a substance or medication that persists beyond the usual duration of substance intoxication or substance withdrawal. This judgement depends on establishing the following. • The substance or medication and the amount and duration of its use is known to be capable of producing the memory disturbance. • The course of the memory disturbance (e.g. onset, trajectory of symptoms, response to treatment) is consistent with causation by the substance or medication.   Note: if the specific substance inducing the amnestic disorder has been identified, it should be classified using the appropriate subcategory: 6D72.10 Amnestic disorder due to use of alcohol 6D72.11 Amnestic disorder due to use of sedatives, hypnotics or anxiolytics 6D72.12 Amnestic disorder due to other specific psychoactive substances, including medications 6D72.13 Amnestic disorder due to use of volatile inhalants. A diagnosis corresponding to the pattern of use of the relevant psychoactive substance (e.g. episode of harmful psychoactive substance use, harmful pattern of psychoactive substance use, substance dependence) may also be assigned. Note: the order of the categories under 6D72.1 Amnestic disorder due to psychoactive substances, including medications, is different from that of other parallel entities (e.g. substance-induced dementia, below), in which the “other specified” category is listed last. This difference is not meaningful; the categories should be used in the same way. Amnestic disorder, other specified cause Essential (required) features • All diagnostic requirements for amnestic disorder are met. • The amnestic disorder is presumed to be attributable to an identified cause that is not adequately captured by any of the other available amnestic disorder categories. Neurocognitive disorders | Amnestic disorder 6D72.1 6D72.Y