Dementia due to Lewy body disease

Definition

Dementia preceding or occurring within one year after the onset of motor parkinsonian signs in the setting of Lewy body disease. Characterized by presence of Lewy bodies, which are intraneuronal inclusions containing α-synuclein and ubiquitin in the brain stem, limbic area, forebrain, and neocortex. Onset is insidious with attentional and executive functioning deficits often present. These cognitive deficits are often accompanied by visual hallucinations and symptoms of REM sleep behaviour disorder. Hallucinations in other sensory modalities, depressive symptoms, and delusions may also be present. The symptom presentation usually varies significantly over the course of days necessitating longitudinal assessment and differentiation from delirium. Spontaneous onset of Parkinsonism within approximately 1 year of the onset of cognitive symptoms is common.

Coding note

This category should never be used in primary tabulation. The codes are provided for use as supplementary or additional codes when it is desired to identify the presence of dementia in diseases classified elsewhere. When dementia is due to multiple aetiologies, code all that apply.

Also indexed as

Nearby in Dementia

• 6D80Dementia due to Alzheimer disease
• 6D81Dementia due to cerebrovascular disease
• 6D83Frontotemporal dementia
• 6D84Dementia due to psychoactive substances including medications
• 6D85Dementia due to diseases classified elsewhere
• 6D86Behavioural or psychological disturbances in dementia
• 4B4YOther specified diseases of the immune system
• 4B4ZDiseases of the immune system, unspecified