title: Reflex and tonic autonomic markers for risk stratification in patients with type 2 diabetes surviving acute myocardial infarction.
abstract: OBJECTIVE
  Diabetic postinfarction patients are at increased mortality risk compared with nondiabetic postinfarction patients. In a substantial number of these patients, diabetic cardiac neuropathy already preexists at the time of the infarction. In the current study we investigated if markers of autonomic dysfunction can further discriminate diabetic postinfarction patients into low- and high-risk groups.
  
  
  METHODS
  We prospectively enrolled 481 patients with type 2 diabetes who survived acute myocardial infarction (MI), were aged ≤ 80 years, and presented in sinus rhythm. Primary end point was total mortality at 5 years of follow-up. Severe autonomic failure (SAF) was defined as coincidence of abnormal autonomic reflex function (assessed by means of heart rate turbulence) and of abnormal autonomic tonic activity (assessed by means of deceleration capacity of heart rate). Multivariable risk analyses considered SAF and standard risk predictors including history of previous MI, arrhythmia on Holter monitoring, insulin treatment, and impaired left ventricular ejection fraction (LVEF) ≤ 30%.
  
  
  RESULTS
  During follow-up, 83 of the 481 patients (17.3%) died. Of these, 24 deaths were sudden cardiac deaths and 21 nonsudden cardiac deaths. SAF identified a high-risk group of 58 patients with a 5-year mortality rate of 64.0% at a sensitivity level of 38.0%. Multivariately, SAF was the strongest predictor of mortality (hazard ratio 4.9 [95% CI 2.4-9.9]), followed by age ≥65 years (3.4 [1.9-5.8]), and LVEF ≤ 30% (2.6 [1.5-4.4]).
  
  
  CONCLUSIONS
  Combined abnormalities of autonomic reflex function and autonomic tonic activity identifies diabetic postinfarction patients with very poor prognoses.
authors.affiliation: Medizinische Klinik und Deutsches Herzzentrum, München der Technischen Universität München, Munich, Germany.
authors.forename: Petra
authors.initials: P
authors.lastname: Barthel
authors.forename: Axel
authors.initials: A
authors.lastname: Bauer
authors.forename: Alexander
authors.initials: A
authors.lastname: Müller
authors.forename: Nadine
authors.initials: N
authors.lastname: Junk
authors.forename: Katharina M
authors.initials: KM
authors.lastname: Huster
authors.forename: Kurt
authors.initials: K
authors.lastname: Ulm
authors.forename: Marek
authors.initials: M
authors.lastname: Malik
authors.forename: Georg
authors.initials: G
authors.lastname: Schmidt
mesh_terms: D000368:Aged; D001341:Autonomic Nervous System / Q000473:pathology / Q000503:physiopathology*; D016757:Death, Sudden, Cardiac / Q000209:etiology; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000401:mortality / Q000503:physiopathology*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications* / Q000401:mortality / Q000503:physiopathology*; D011446:Prospective Studies; D012018:Reflex / Q000502:physiology*