1177 The Patient Who Never Stopped Dreaming

A 74-year-old man with REM sleep behavior disorder, visual hallucinations, and new cognitive deficits perceived the world as a persistent dream-like state for two years, describing objects as unreal, cartoon-like, and distorted. Polysomnography confirmed REM sleep without atonia. The authors argue that people with dementia with Lewy bodies experience a spectrum of sleep disorders and complex visual hallucinations reflecting impaired sensory integration during the transition from mild cognitive impairment to dementia. They contend that sleep clinicians must recognize visual-spatial processing disorders in any patient presenting with sleep-related hallucination, as these may be stigmatized or misattributed to REM sleep behavior disorder.

Study at a glance

Abstract

Sleep-related hallucination (SRH) is a parasomnia that may be encountered in the form of altered dream mentation in α-synucleinopathies, particularly in the setting of dementia with Lewy bodies (DLB). Visual hallucinations (VH) are complex, well-formed, episodes that represent a core diagnostic criterion for DLB. We report a patient who presented with REM sleep behavior disorder (RBD), VH, and perceiving the world as if he were in a persistent dream-like state coinciding with new cognitive deficits. A 74 y/o male presented with a subjective perception of “being in a constant dream-like state” for the past 2 years. He describes “atypical nightmares and hypnopompic visual hallucinations” The Patient describes that objects do not feel real, but appear drawn out as in a cartoon. He feels “disconnected” from the environment and perceives images as “distant, distorted, unreal, but also very colorful, vivid, saturated as a cartoon animation sequence. He no longer feels safe to drive and his wife reveals a failure to appreciate depth leading to an increased frequency of falls. Ophthalmologic exam was unremarkable including normal visual acuity, field testing, and color vision. ESS: 8, Sleep log: subjective total sleep- 7-8 hrs/night. Polysomnography conforms the presence of dream enactment behaviors and REM sleep without atonia meeting the diagnostic criteria for RBD. AHI-3, SaO2: 92%. REM latency: 92 minutes. People with DLB experience a spectrum of sleep disorders, especially RBD, but also experience a range of sleep and wake-related complex visual hallucinations. The latter may reflect impairment in sensory integration, particularly during the transformation from mild cognitive impairment (MCI) to DLB due to alteration in visual sensory processing. Sleep clinicians serve a critical role in the evaluation of SRH, and differentiating these from other mimics, such as VH related to neuropsychiatric conditions. Due to their bizarre and perplexing presentation, visual-spatial processing disorders (VSP) in DLB may be stigmatized, dismissed, or attributed to RBD. Sleep clinicians must therefore include recognizing VSP in any patient presenting with SRH.