Episodic Coma in Lewy Body Disorders: An Observational Report

and Purpose: Episodes of unresponsiveness are one of several criteria used to diagnose dementia with Lewy bodies and are also seen in people with Parkinson's disease dementia. Patients examined during episodes of coma, whose evaluations found no other explanation than the neurological disorder, have not been described. This paper describes four cases, seen in the past two years. The objective is to bring this uncommon phenomenon to the attention of hospital based neurologists and to demonstrate that this may not be due to autonomic dysfunction.

These are brief case descriptions by medical personnel observing affected patients supplemented by family reports of similar episodes described on the internet.

Four cases are described, all older men with either dementia with Lewy bodies or Parkinson's disease dementia, who had single, or multiple episodes of otherwise unexplained coma and were examined during a spell. IRB approval waived.

Episodic coma may occur in demented patients with an alpha-synucleinopathy and is the likely explanation when evaluations have found no other cause. This information will reassure the family and patient that this is the likely explanation but that spells may recur.