Dementia with Lewy Bodies Jae Woo Kim, M.D. Department of Neurology Dong-A University Hospital

Dementia with Lewy Bodies Second most common cause of degenerative dementia : prevalence 19% (52% for AD, McKeith, 1992) Lewy body pathology : third most common cause of dementia, 7.7% (71% for AD change & 34% for CVD)

Lewy body

Classification of Lewy body disease (Kosaka et al, 1993) Cortex brainstem Diffuse type Common form : DLB + AD Pure form : DLB Transitional type Brainstem type : Parkinson’s disease

Diagnostic Criteria of DLB Progressive cognitive decline Core features fluctuating cognition recurrent visual hallucinations parkinsonism Supportive features repeated falls syncope transient loss of consciousness neuroleptic sensitivity systematized delusions hallucinations in other modalities

Neuropathology Predilection areas cortex - ant. frontal & temporal, cingulate, insula subcortex - substantia nigra, nucleus basalis of Meynert locus ceruleus, raphe N, amygdala More neuronal loss than in AD SN, nb Meynert, frontal lobe Neurofibrillary tangles negative correlation btw neocortical LB & NFT density scarcity of NFT - distinct from AD

Neurochemistry Acetylcholine ChAT - more severe deficit than in AD correlated with visual hallucination & cognitive impairment Increased postsynaptic muscarinic receptors Dopamine 40-60% loss in striatum (80% in PD)

PET Studies Fluorodopa reduced uptake in striatum FDG more severe glucose hypometabolism in T-P-O association cortices (esp. medial & lateral occipital lobes) in DLB and medial temporal & cingulate areas in AD

DLB vs Parkinson’s Disease Less DA neuronal loss in SN Less DA depletion in striatum Decreased HVA / DA ratio : turnover rate Reduced ChAT activity in striatum : rare rest tremor, milder parkinsonism Reduced D2 receptors : less responsiveness to LD

Parkinsonian Features Less responsiveness to LD Less asymmetricity Neuroleptic sensitivity Rare rest tremor

DAT SPECT normal DLB

DAT SPECT HMPAO-SPECT

Clinical Characteristics of Patients with DLB Case No. (n=10) Sex/Age FC / VH / P K-MMSE (min / max) SPECT (Hypoperfusion area) IPT SPECT 1 M/66 +/-/+ 23/29 Both F-T-P-O 0.77/0.54 2 M/61 +/+/+ 15/19 0.94/1.07 3 M/75 6/11 0.44/0.48 4 M/79 10/15 0.76/0.73 5 M/60 6/9 Both T-P-O 0.88/0.61 6 M/70 17/22 Left T-P-O 0.43/0.70 7 M/58 17/25 0.47/0.54 8 0.72/0.86 9 18/25 Both F-T-P 0.36/0.54 10 M/80 23/28 1.16/1.13

Responsiveness to Levodopa

Responsiveness to Acetylcholinesterase Inhibitor