title: Recognizing increased risk of depressive comorbidity after myocardial infarction: looking for 4 symptoms of anxiety-depression.
abstract: BACKGROUND
  Screening for depression in myocardial infarction (MI) patients must be improved: (1) depression often goes unrecognized and (2) anxiety has been largely overlooked as an essential feature of depression in these patients. We therefore examined the co-occurrence of anxiety and depression after MI, and the validity of a brief mixed anxiety-depression index as a simple way to identify post-MI patients at increased risk of comorbid depression.
  
  
  METHODS
  One month after MI, 176 patients underwent a psychiatric interview and completed the Beck Depression Inventory (BDI) and the Symptoms of Anxiety-Depression index (SAD(4)) containing four symptoms of anxiety (tension, restlessness) and depression (feeling blue, hopelessness).
  
  
  RESULTS
  Thirty-one MI patients (18%) had comorbid depression and 37 (21%) depressive or anxiety disorder. High factor loadings and item-total correlations (SAD(4), alpha = 0.86) confirmed that symptoms of anxiety and depression co-occurred after MI. Mixed anxiety-depression (SAD(4)>or=3) was present in 90% of depressed MI patients and in 100% of severely depressed patients. After adjustment for standard depression symptoms (BDI; OR = 4.4, 95% CI 1.6-12.1, p = 0.004), left ventricular ejection fraction, age and sex, mixed anxiety-depression symptomatology was associated with an increased risk of depressive comorbidity (OR = 11.2, 95% CI 3.0-42.5, p < 0.0001). Mixed anxiety-depression was also independently associated with depressive or anxiety disorder (OR = 9.2, 95% CI 3.0-27.6, p < 0.0001).
  
  
  CONCLUSIONS
  Anxiety is underrecognized in post-MI patients; however, the present findings suggest that anxiety symptomatology should not be overlooked in these patients. Depressive comorbidity after MI is characterized by symptoms of mixed anxiety-depression, after controlling for standard depression symptoms. The SAD(4) represents an easy way to recognize the increased risk of post-MI depression.
authors.affiliation: Department of Psychology and Health, Tilburg University, Tilburg, The Netherlands. denollet@uvt.nl
authors.forename: Johan
authors.initials: J
authors.lastname: Denollet
authors.forename: Jacqueline J
authors.initials: JJ
authors.lastname: Strik
authors.forename: Richel
authors.initials: R
authors.lastname: Lousberg
authors.forename: Adriaan
authors.initials: A
authors.lastname: Honig
mesh_terms: D001008:Anxiety Disorders / Q000175:diagnosis* / Q000453:epidemiology*; D015897:Comorbidity; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000453:epidemiology*; D003937:Diagnosis, Differential; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000453:epidemiology*; D012307:Risk Factors; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D013997:Time Factors