Chronic interferon-alpha administration disrupts sleep continuity and depth in patients with hepatitis C: association with fatigue, motor slowing, and increased evening cortisol.
BACKGROUND
Consequences of chronic exposure to cytokines of the innate immune system on sleep in humans and the association of cytokine-induced sleep alterations with behavior, motor performance, and cortisol secretion are unknown.


METHODS
Thirty-one patients with hepatitis C without pre-existing sleep disorders underwent nighttime polysomnography, daytime multiple sleep latency testing, behavioral assessments, neuropsychological testing, and serial blood sampling at baseline and after ∼12 weeks of either treatment with the innate immune cytokine interferon (IFN)-alpha (n = 19) or no treatment (n = 12). Fatigue and sleepiness were assessed using the Multidimensional Fatigue Inventory and Epworth Sleepiness Scale.


RESULTS
Interferon-alpha administration led to significant increases in wake after sleep onset and significant decreases in stage 3/4 sleep and sleep efficiency. Rapid eye movement latency and stage 2 sleep were significantly increased during IFN-alpha treatment. Decreases in stage 3/4 sleep and increases in rapid eye movement latency were associated with increases in fatigue, whereas decreases in sleep efficiency were associated with reduced motor speed. Increased wake after sleep onset was associated with increased evening plasma cortisol. Despite IFN-alpha-induced increases in fatigue, daytime sleepiness did not increase. In fact, IFN-alpha-treated patients exhibited decreased propensity to fall asleep during daytime nap opportunities.


CONCLUSIONS
Chronic exposure to an innate immune cytokine reduced sleep continuity and depth and induced a sleep pattern consistent with insomnia and hyperarousal. These data suggest that innate immune cytokines may provide a mechanistic link between disorders associated with chronic inflammation, including medical and/or psychiatric illnesses and insomnia, which, in turn, is associated with fatigue, motor slowing, and altered cortisol.
Raison
Charles L
CL
Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
Rye
David B
DB
Woolwine
Bobbi J
BJ
Vogt
Gerald J
GJ
Bautista
Breanne M
BM
Spivey
James R
JR
Miller
Andrew H
AH
D000998:Antiviral Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D016022:Case-Control Studies; D005221:Fatigue / Q000139:chemically induced*; D005260:Female; D006526:Hepatitis C / Q000097:blood / Q000150:complications / Q000188:drug therapy*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000008:administration & dosage / Q000009:adverse effects* / Q000097:blood / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D011092:Polyethylene Glycols / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D011930:Reaction Time / Q000187:drug effects*; D047889:Receptors, Tumor Necrosis Factor, Type II / Q000097:blood; D011994:Recombinant Proteins; D012893:Sleep Wake Disorders / Q000097:blood / Q000139:chemically induced* / Q000150:complications; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
D000998:Antiviral Agents; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D047889:Receptors, Tumor Necrosis Factor, Type II; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D011092:Polyethylene Glycols; C417083:peginterferon alfa-2b; C100416:peginterferon alfa-2a; D006854:Hydrocortisone