The relationship between sleep quality and neurocognition in bipolar disorder.
BACKGROUND
Sleep and circadian rhythm disruptions are prominent, trait-like features of bipolar disorder (BD) which precede the onset of mood episodes. Neurocognitive impairments also characterize BD not only during acute phases of the illness but also during remission. Although the relationship between these two debilitating aspects of the illness might seem intuitive, very little is known about their relationship. We examined the association between sleep dysfunction and neurocognition in BD.


METHODS
In a sample of 117 BD patients (mean age=45.0±10.7; 59.0% (n=69) male), neurocognitive functioning was assessed using the MATRICS Consensus Cognitive Battery (MCCB). Sleep quality data were collected using the Epworth Sleepiness Scale (ESS) and the Pittsburgh Sleep Quality Index (PSQI). Partial Pearson correlations tested for a relationship between sleep and neurocognition. Path analyses were conducted to examine the hypothesized direct influence of sleep disruption on neurocognition.


RESULTS
Higher levels of sleep disruptions were associated with a more severe clinical presentation and poorer performance in social cognition, visual learning and working memory. Social cognition and working memory were directly (negatively) predicted by sleep disruptions.


CONCLUSIONS
The study was limited by a relatively small sample size and the lack of behavioral and biological objectives measure of activity/rest cycles.


CONCLUSIONS
Our study suggests that in patients with BD, sleep disruptions have a detrimental effect on general level of psychopathology and contribute directly to impaired cognitive functioning in the domains of social cognition and working memory. More research using objective measurement of sleep should be pursued to support these data and to further investigate the causal relationship between these disabling aspects of the illness.
Icahn School of Medicine at Mount Sinai, Departments of Psychiatry and Neuroscience, United States.
Manuela
M
Russo
Icahn School of Medicine at Mount Sinai, Departments of Psychiatry and Neuroscience, United States.
Katie
K
Mahon
Icahn School of Medicine at Mount Sinai, Departments of Psychiatry and Neuroscience, United States.
Megan
M
Shanahan
Icahn School of Medicine at Mount Sinai, Departments of Psychiatry and Neuroscience, United States.
Elizabeth
E
Ramjas
Icahn School of Medicine at Mount Sinai, Departments of Psychiatry and Neuroscience, United States.
Carly
C
Solon
Icahn School of Medicine at Mount Sinai, Departments of Psychiatry and Neuroscience, United States.
Shaun M
SM
Purcell
Icahn School of Medicine at Mount Sinai, Departments of Psychiatry and Neuroscience, United States; James J Peters VA Medical Center Bronx, NY, United States. Electronic address: Katherine.burdick@mssm.edu.
Katherine E
KE
Burdick
D000328:Adult; D000368:Aged; D001714:Bipolar Disorder / Q000150:complications* / Q000523:psychology; D002940:Circadian Rhythm; D003071:Cognition; D003072:Cognition Disorders / Q000209:etiology* / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term; D008875:Middle Aged; D012891:Sleep Apnea Syndromes / Q000209:etiology* / Q000523:psychology; D012919:Social Behavior
Bipolar disorder; Neurocognition; Sleep disruption; Sleep quality