# Presentation: 245697

## Dementia with Lewy Bodies

**American Academy of Neurology**
**John Hart, Jr., M.D.**

## Dementia with Lewy Bodies

**Definition: clinically defined by the presence of dementia, prominent hallucinations and delusions (yet sensitive to antipsychotic medications), fluctuations in alertness, and gait/balance disorder ****(McKeith et al., Neurology 1996;47:1113-1124)**
**Accounts for up to 20-30% of degenerative dementias ****(Hansen et al., Neurology 1990;40:1-8)**
**Second in occurrence behind AD**

## Dementia with Lewy Bodies

**Autopsy shows 15-36% of demented cases presenting for autopsy have Lewy Bodies (LB) in neocortex and brainstem**
**Most also AD changes**
**Typically include pure dementia cases with cortical Lewy Bodies and those those with AD+LB under Dementia with Lewy Bodies**

## Dementia with Lewy Bodies

## Demographics

**Age of onset comparable to AD **
**Males more susceptible (1.5:1) and have worse prognosis**
**Duration may be rapid (1-5 years) or typical to AD in other cases**

## Dementia with Lewy Bodies

**Established clinical consensus criteria ****(McKeith et al., Neurology 1996;47:1113-1124)**
**Dementia (DSM-IV) where prominent or persistent memory impairments may not necessarily occur in the early stages but occurs with progression.  Attention, frontal-subcortical, and visuospatial skills may be prominent**

## Dementia with Lewy Bodies

**Has two of the following core features for probable and one for possible DLB**
**Fluctuating cognition with pronounced variations in attention and alertness**
**Occurs in 80-90% of DLB, only 20% of AD**
**Recurrent visual hallucinations that are typically well formed and detailed**
**Spontaneous motor features of parkinsonism**

## Dementia with Lewy Bodies 

**Features supportive of the diagnosis are:**
**Repeated falls**
**Syncope**
**Transient loss of consciousness**
**Neuroleptic sensitivity**
**Systematized delusions**
**Hallucinations in other modalities**

## Dementia with Lewy Bodies

**Neuropsychology:**
**Impaired visuoconstructional skills and attention with relative sparing of memory**
**Imaging: **
**MRI shows DLB patients with hippocampal volume between those of normal controls and AD patients ****(Hashimoto et al., Neurology 1998;51:357-362)**** **
**More hypoperfusion in the occipital lobes than AD ****(Knopman et al., Neurology 2001;56:1143-1153)**

## Pathology

**Lewy bodies in the cortex and brainstem**
**Subcortical nuclei, limbic cortex, neocortex (temporal > frontal = parietal)**
**May have beta amyloid deposition and plaques like AD, but few neurofibrillary tangles**

## Dementia with Lewy Bodies

## Dementia with Lewy Bodies

**Term is conventionally used in clinical and pathological diagnoses **
**No other specific code captures the clinical or pathological spectrum**
**General dementia or AD diagnosis (290 or 331) ignores established criteria, allows no tracking of DLB, and is the 2****nd**** largest etiology of neurodegenerative dementias**

## Dementia with Lewy Bodies

**Differs from the other codes including AD, Parkinson’s disease and dementia **
**AD ******** early hallucinations, fluctuation in alertness, sensitivity to neuroleptics are important to differentiate**
**Parkinson’s disease and dementia ******** the dementia with PD is subcortical with different symptoms**

## Dementia with Lewy Bodies

## Dementia with Lewy Bodies

## Dementia with Lewy Bodies