Off-line memory consolidation impairments in multiple sclerosis patients receiving high-dose corticosteroid treatment mirror consolidation impairments in depression.
BACKGROUND
Sleep supports the consolidation of procedural memory, however patients with major depression show impaired motor memory performance after a night of sleep. It was hypothesized that this impairment is related to hypothalamic-pituitary-adrenal (HPA) axis dysfunction. We tested if high-dose administration of corticosteroids impairs off-line motor memory consolidation in patients with multiple sclerosis (MS).


METHODS
Nine patients with MS receiving high-dose corticosteroid therapy (methylprednisolone) and nine MS patients receiving alternative therapy (mitoxantrone) were assessed using a sequential finger tapping task before and after a night with polysomnography. In addition, nine patients with major depression (MD) receiving antidepressants and nine healthy controls were assessed.


RESULTS
Although the four groups did not differ in practice-dependent learning, healthy subjects and MS patients receiving mitoxantrone showed markedly overnight-improvements in tapping performance of 17% and 24% while MS patients receiving high-dose corticosteroid therapy and depressed patients showed -9% and -10% overnight decrease. MS patients with and without corticosteroid therapy did not differ in their amount of REM sleep, nor did MD patients and healthy controls. In addition, we did not find any correlation between REM sleep and memory consolidation.


CONCLUSIONS
Our results show that a strong intervention into the HPA system like in MS high-dose corticosteroid therapy impairs off-line motor memory consolidation comparable to the impairments seen in depressed patients. We propose therefore that depression-related changes in plasma corticosteroid levels rather than in sleep per se underlie off-line memory consolidation impairments in MD.
Dresler
Martin
M
Max Planck Institute of Psychiatry, Munich, Germany. dresler@mpipsykl.mpg.de
Genzel
Lisa
L
Kluge
Michael
M
Schüssler
Petra
P
Weber
Frank
F
Rosenhagen
Marcus
M
Steiger
Axel
A
D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000009:adverse effects*; D000328:Adult; D000368:Aged; D003863:Depression / Q000150:complications* / Q000503:physiopathology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000187:drug effects / Q000502:physiology; D008569:Memory Disorders / Q000139:chemically induced / Q000209:etiology* / Q000503:physiopathology; D008775:Methylprednisolone / Q000008:administration & dosage / Q000009:adverse effects; D008875:Middle Aged; D008942:Mitoxantrone / Q000008:administration & dosage / Q000009:adverse effects; D009103:Multiple Sclerosis / Q000188:drug therapy* / Q000503:physiopathology; D018696:Neuroprotective Agents / Q000008:administration & dosage / Q000009:adverse effects; D011597:Psychomotor Performance / Q000187:drug effects / Q000502:physiology; D012890:Sleep / Q000187:drug effects / Q000502:physiology; D012893:Sleep Wake Disorders / Q000139:chemically induced / Q000209:etiology* / Q000503:physiopathology
D000305:Adrenal Cortex Hormones; D018696:Neuroprotective Agents; D008942:Mitoxantrone; D008775:Methylprednisolone