Dementia with Lewy bodies - a clinical and neurological approach

Sammanfattning: Dementia with Lewy bodies (DLB) is a dementia disorder, clinically characterized by fluctuating cognitive impairment, attention deficits, visual hallucinations, parkinsonism and other neuropsychiatric features. Sensitivity to neuroleptic medication is a common finding. In the present study 24% of 200 autopsied cases, within the Lund longitudinal prospective dementia study fulfilled the clinical diagnostic criteria of DLB. Compared to clinical Alzheimer (AD) cases, these cases also showed clinical signs of frontal dysfunction. Furthermore they had a greater degree of deterioration of dementia and were more reliant on outside assistance when compared to clinical AD cases. The blood pressure decreased during dementia and many cases became hypotensive and orthostatic. The pharmacological load was heavier in clinical DLB compared to AD. The neuropathological results revealed Lewy bodies in 38% of the clinically defined DLB cases. These cases also had other pathological changes such as Alzheimer pathology, vascular pathology and a degeneration of dopaminergic and cholinergic nuclei, eg substantia nigra and nucleus basalis Meynert. Clinical DLB cases lacking Lewy bodies were characterised by Alzheimer pathology combined with frontally selective incomplete white matter infarcts. EEG and regional cerebral blood flow measurements were not helpful in distinguishing between AD and DLB or in separating cases with Lewy body pathology from those without. When individual cases were analysed clinico-pathologically, the DLB symptoms could often be explained by the combinations of pathologies. The study illustrates the difficulties of the clinical recognition of a specific pathological entity in individuals and the complex relation between brain pathology, clinical symptoms, medication and its adverse effects.