Unexpected REM sleep excess associated with a pontine lesion in multiple sclerosis

Abstract

Sleep disorders are prevalent in patients with multiple sclerosis. In contrast, a frank increase of rapid eye movement (REM) sleep time is a rare phenomenon, mostly described in the context of REM sleep rebound (after sleep deprivation, abrupt withdrawal of antidepressants or neuroleptics, and during the first night of ventilation for severe sleep apnea), but not in link with specific brain lesions. We incidentally found an isolated, marked increase in REM sleep time (200 min, 40% of total sleep time, normative values: 18.2-20.3%) and in rapid eye movements density during REM sleep in a patient with a secondary progressive multiple sclerosis, associated with an anterior pontine demyelinating lesion on magnetic resonance imaging. This result suggests that a network blocking REM sleep in the pons has been damaged.

Trial registration: ClinicalTrials.gov NCT03339817.

Keywords: REM sleep; multiple sclerosis; pontine lesion.

Figure 1. Increased REM sleep time associated with a pontine lesion.

(A) Hypnogram of the patient, showing excessive rapid eye movement (REM) sleep time, representing 200 minutes and 40.4% of total sleep time (normal: 18.2–20.3%). 1, 2, and 3 = non-REM sleep, stages N1, N2, and N3; EEG = electroencephalogram; R = REM stage; W = wake. (B) Magnetic resonance imaging of the patient (sequence T2), axial and sagittal sections, showing the pontine lesion (red arrows).