title: Sleep is related to physical function and emotional well-being after cardiac surgery.
abstract: BACKGROUND
  Emotional well-being and physical function are important quality-of-life outcomes after cardiac surgery. Alterations in sleep patterns, including sleep deprivation and altered circadian patterning, also are common. The relations among sleep pattern alterations, physical function, and emotional well-being are not well understood.
  
  
  OBJECTIVE
  This study aimed to examine the relations of sleep patterns to physical function and emotional well-being 4 and 8 weeks after cardiac surgery.
  
  
  METHODS
  Cardiac surgery patients (n = 72) wore wrist actigraphs and completed sleep diaries for 3 days during postoperative weeks 4 and 8. They also completed the Epworth Sleepiness Scale, the Pittsburgh Sleep Quality Index, and the Medical Outcomes Survey Short Form 36 preoperatively and at postoperative weeks 4 and 8. Pearson correlations and hierarchical multiple regression analysis were used to analyze the data.
  
  
  RESULTS
  Mean sleep efficiency was 71% at 4 weeks and 74% at 8 weeks, as measured with wrist actigraphy. According to participants' self-report, 64% experienced sleep disturbance at 4 weeks and 47% at 8 weeks. Sleep pattern variables, including sleep efficiency and self-reported sleep quality, explained 16% of the variance in physical function at 4 weeks. Self-reported sleep quality explained 8% of the variance in physical function at 8 weeks as well as 12% of the variance in emotional well-being at postoperative week 4 and 13% of the variance at postoperative week 8, after control was used for the contributions of baseline physical function, emotional well-being, age, and sex.
  
  
  CONCLUSIONS
  The results suggest that sleep contributes to both physical functional and emotional well-being 4 and 8 weeks after cardiac surgery.
authors.affiliation: Research School of Nursing, University of Medicine and Dentistry of New Jersey, Newark, USA.
authors.forename: Nancy S
authors.initials: NS
authors.lastname: Redeker
authors.forename: Jeanne S
authors.initials: JS
authors.lastname: Ruggiero
authors.forename: Christine
authors.initials: C
authors.lastname: Hedges
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008603:Mental Health; D008875:Middle Aged; D009511:New England / Q000453:epidemiology; D017286:Polysomnography; D011788:Quality of Life; D012044:Regression Analysis; D017678:Sex Distribution; D012737:Sex Factors; D012893:Sleep Wake Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology / Q000523:psychology; D011795:Surveys and Questionnaires