title: The association of heart-rate variability with cardiovascular risk factors and coronary artery calcification: a study in type 1 diabetic patients and the general population.
abstract: OBJECTIVE
  To examine the association of heart-rate variability with cardiovascular risk factors and coronary calcification in type 1 diabetic and nondiabetic subjects without a history of cardiovascular disease. Reduced heart-rate variability is associated with increased risk of coronary events. Whether it is associated with coronary atherosclerosis is unknown.
  
  
  METHODS
  Power spectral analysis was used to define heart-rate variability in a cross-sectional study of 160 type 1 diabetic patients and 163 randomly selected nondiabetic adults from the general population aged 30-55 years. Coronary artery calcification was measured using electron beam-computed tomography.
  
  
  RESULTS
  Reduced heart-rate variability was associated with similar risk factors in the diabetic and nondiabetic subjects, namely higher HbA(1c), triglycerides, systolic blood pressure, BMI, and albumin excretion rate. Reduced heart-rate variability was significantly associated with coronary artery calcification in all subjects (odds ratio per tertile lower total power = 1.5, P = 0.01). This association was not independent of blood pressure or BMI (odds ratio on adjustment = 1.3, P = 0.1).
  
  
  CONCLUSIONS
  Reduced heart-rate variability clusters with other cardiovascular disease risk factors, especially those that are more common in the insulin resistance syndrome, and is associated with increased coronary calcification in asymptomatic young adults. Whether reduced heart-rate variability leads to other risk factor disturbances or mediates the effects of other risk factors on atherosclerosis deserves further study.
authors.affiliation: Deparetment of Epidemiology and Public Health, Royal Free and University College London Medical School, 1-19 Torrington Place, London WC1E 6BT, U.K. helen@public-health.ucl.ac.uk
authors.forename: H M
authors.initials: HM
authors.lastname: Colhoun
authors.forename: D P
authors.initials: DP
authors.lastname: Francis
authors.forename: M B
authors.initials: MB
authors.lastname: Rubens
authors.forename: S R
authors.initials: SR
authors.lastname: Underwood
authors.forename: J H
authors.initials: JH
authors.lastname: Fuller
mesh_terms: D000328:Adult; D000419:Albuminuria; D015992:Body Mass Index; D002114:Calcinosis / Q000453:epidemiology*; D002318:Cardiovascular Diseases / Q000453:epidemiology*; D017023:Coronary Angiography; D003327:Coronary Disease / Q000453:epidemiology*; D003920:Diabetes Mellitus / Q000453:epidemiology; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology*; D003925:Diabetic Angiopathies / Q000453:epidemiology*; D015444:Exercise; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008055:Lipids / Q000097:blood; D008074:Lipoproteins / Q000097:blood; D008131:London; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology; D012042:Registries; D012307:Risk Factors; D012907:Smoking; D013599:Systole; D014057:Tomography, X-Ray Computed; D014280:Triglycerides / Q000097:blood
chemical_list: D006442:Glycated Hemoglobin; D008055:Lipids; D008074:Lipoproteins; D014280:Triglycerides