Prevalence of QT prolongation in a type 1 diabetic population and its association with autonomic neuropathy. The Neuropathy Study Group of the Italian Society for the Study of Diabetes

Diabet Med. 1993 Dec;10(10):920-4. doi: 10.1111/j.1464-5491.1993.tb00007.x.


The prevalence of QT prolongation in a large random sample of Type 1 diabetic patients in Piemonte, Italy and its association with autonomic neuropathy were assessed. Three hundred and seventy-nine Type 1 diabetic patients (age 15-59) with (94, DAN+) and without (280, DAN-) autonomic neuropathy and 118 non-diabetic control subjects participated in the study. QT interval was measured on an ECG recorded at rest and QTc calculated according to Bazett's formula. QTc was greater than 0.440 s in 7.6% (95% CI 2.9-12.3) of control subjects, 25.6% (21.0-30.0) of diabetic patients, 30.8% (21.5-40.1) of DAN+, 23.9% (18.9-28.9) of DAN-. QTc was greater than 0.460 s (mean + 2SD of QTc in control subjects) in 11.7% (8.5-14.9) of diabetic patients, 18.1% (10.3-25.9) of DAN+, 9.6% (6.2-13.0) of DAN-. QT was above the 95% upper limit for the control subjects in the plot of measured QT against RR interval in 21.4% (17.3-25.5) of diabetic patients, 26.6% (17.7-35.5) of DAN+, 19.3% (14.7-23.9) of DAN-. No correlation was found between QT interval and age or disease duration. The prevalence of QT prolongation was higher in diabetic patients than in control subjects and in DAN+ than in DAN-.

Publication types

  • Comparative Study

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Analysis of Variance
  • Blood Pressure
  • Diabetes Mellitus, Type 1 / physiopathology*
  • Diabetic Neuropathies / epidemiology
  • Diabetic Neuropathies / physiopathology*
  • Female
  • Heart Rate
  • Humans
  • Long QT Syndrome / complications
  • Long QT Syndrome / epidemiology*
  • Long QT Syndrome / physiopathology
  • Male
  • Middle Aged
  • Posture
  • Prevalence
  • Reference Values
  • Respiration