title: Insomnia in patients with unexplained chest pain.
abstract: OBJECTIVE
  The current study was designed (1) to assess insomnia symptoms and sleep-related beliefs in a population of patients presenting in emergency department with unexplained chest pain (UCP) and (2) to examine the associations between insomnia and pain.
  
  
  METHODS
  This is a report of secondary data from a cross-sectional study performed in the emergency department of 2 academic hospitals. Patients with UCP seen in an emergency department were assessed using sleep questionnaires and the Anxiety Disorders Interview Schedule for Diagnostic and Statistical Manual of Mental Disorders, fourth edition.
  
  
  RESULTS
  Nearly every second patient with UCP (44%) seen in an emergency department suffered from clinically significant insomnia symptoms. Most patients with an anxiety or a mood disorder had insomnia, but a minority of patients with insomnia had an anxiety or a mood disorder. Insomniacs with an anxiety disorder were similar to insomniacs without comorbid anxiety for sleep-related beliefs and depressive symptoms, and both groups of insomniacs reported more depressive symptoms and faulty beliefs than both groups of good sleepers, i.e., either with or without an anxiety disorder. Results from regression analyses revealed that insomnia was associated with pain on univariate regression analysis and accounted for 1.3% of the variance in both pain intensity and interference. However, this association was rendered nonsignificant when additional variables were added to the model.
  
  
  CONCLUSIONS
  Insomnia symptoms are an important, but often disregarded, feature present in a significant proportion of patients with UCP. As insomnia showed stronger associations with pain than anxiety or depression, it may represent an important factor contributing to the development and recurrence of UCP.
authors.affiliation: School of Psychology, Université Laval, Québec, Canada (GB, G F-B). Electronic address: genevieve.belleville@psy.ulaval.ca.
authors.forename: Geneviève
authors.initials: G
authors.lastname: Belleville
authors.affiliation: School of Psychology, Université Laval, Québec, Canada (GB, G F-B); The University-Affiliated Hospital of Lévis, Québec, Canada (G F-B, JP, RF).
authors.forename: Guillaume
authors.initials: G
authors.lastname: Foldes-Busque
authors.affiliation: The University-Affiliated Hospital of Lévis, Québec, Canada (G F-B, JP, RF); Department of Family Medicine and Emergency Medicine, Université Laval, Québec, Canada (JP, RF).
authors.forename: Julien
authors.initials: J
authors.lastname: Poitras
authors.affiliation: Sacré-Coeur Hospital Research Centre, Québec, Canada (J-M C, JGD).
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Chauny
authors.affiliation: Sacré-Coeur Hospital Research Centre, Québec, Canada (J-M C, JGD).
authors.forename: Jean G
authors.initials: JG
authors.lastname: Diodati
authors.affiliation: The University-Affiliated Hospital of Lévis, Québec, Canada (G F-B, JP, RF); Department of Family Medicine and Emergency Medicine, Université Laval, Québec, Canada (JP, RF).
authors.forename: Richard
authors.initials: R
authors.lastname: Fleet
authors.affiliation: Department of Psychology, Université du Québec à Montréal, Montréal, Canada (AM); Intervention Axis, Centre de Recherche Fernand-Seguin, Mentréal, Canada (AM).
authors.forename: André
authors.initials: A
authors.lastname: Marchand
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001008:Anxiety Disorders / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D002637:Chest Pain / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D003430:Cross-Sectional Studies; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011792:Quebec / Q000453:epidemiology; D012720:Severity of Illness Index; D007319:Sleep Initiation and Maintenance Disorders / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D011795:Surveys and Questionnaires