title: Association between cardiac autonomic dysfunction and inflammation in type 1 diabetic patients: effect of beta-blockade.
abstract: OBJECTIVE
  To assess the relationship between cardiac autonomic dysfunction and inflammation in patients with type 1 diabetes and whether beta-blocker therapy might improve both abnormalities in these patients.
  
  
  RESULTS
  We studied 49 patients with type 1 diabetes (age 50.5 +/- 11 years, 33 men). Serum levels of high-sensitivity C-reactive protein, as a marker of inflammation, and frequency-domain heart rate variability (HRV) on 24 h Holter monitoring, as a measure of cardiac autonomic function, were assessed in all patients. Twenty-one patients with depressed HRV were subsequently randomized to receive atenolol (50 mg daily) or no-beta-blockade. HRV and C-reactive protein were re-assessed after 3-4 weeks from randomization. An inverse correlation was found between C-reactive protein levels and HRV parameters, with the highest r coefficient shown with low-frequency (LF) power (r = -0.38; P = 0.007). Furthermore, C-reactive protein serum levels were significantly higher in patients with bottom quartile values of LF power compared with patients with values in the three top quartiles (4.64 +/- 2.8 vs.1.79 +/- 1.6 mg/L, respectively; P = 0.003), also after adjustment for potential confounding variables (P = 0.013). HRV parameters improved significantly in patients treated with atenolol, but not in the no-atenolol group. Furthermore, C-reactive protein levels decreased in the beta-blockade group, but not in the no-beta-blockade group (P = 0.04 for changes between groups).
  
  
  CONCLUSIONS
  In type 1 diabetic patients, serum C-reactive protein levels are significantly associated with depressed HRV; the favourable effects of beta-blockade on both HRV parameters and C-reactive protein serum levels suggest that autonomic nervous system may have significant modulator effects on inflammation.
authors: Istituto di Cardiologia, Università Cattolica del Sacro Cuore, Largo A. Gemelli, 8, 00168 Roma, Italy. g.a.lanza@inwind.it
authors: Gaetano Antono
authors: GA
authors: Lanza
authors: Dario
authors: D
authors: Pitocco
authors: Eliano Pio
authors: EP
authors: Navarese
authors: Alfonso
authors: A
authors: Sestito
authors: Gregory Angelo
authors: GA
authors: Sgueglia
authors: Andrea
authors: A
authors: Manto
authors: Fabio
authors: F
authors: Infusino
authors: Tittania
authors: T
authors: Musella
authors: Giovanni
authors: G
authors: Ghirlanda
authors: Filippo
authors: F
authors: Crea
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D001145:Arrhythmias, Cardiac / Q000188:drug therapy; D001262:Atenolol / Q000627:therapeutic use*; D001342:Autonomic Nervous System Diseases / Q000188:drug therapy*; D002097:C-Reactive Protein / Q000378:metabolism; D003922:Diabetes Mellitus, Type 1 / Q000188:drug therapy*; D003929:Diabetic Neuropathies / Q000188:drug therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009205:Myocarditis / Q000150:complications*
chemical_list: D000319:Adrenergic beta-Antagonists; D001262:Atenolol; D002097:C-Reactive Protein