Diabetes with and without autonomic neuropathy was associated with slightly longer QTc intervals compared to normal subjects (435±24 ms and 430±20 ms vs 423±15 ms, p=0.05).
Cross-Sectional (n=111)
Does diabetic autonomic neuropathy alter QT interval length compared to normal subjects and diabetics without neuropathy?
Diabetic patients, particularly those with autonomic neuropathy, exhibit small but significant prolongations in QT and QTc intervals, suggesting autonomic impairment affects ventricular repolarization.
Absolute Event Rate: 435% vs 423%
p-value: p=0.05
QT interval length was measured in ECG recordings from three groups of age-matched male subjects: 36 normal subjects, 41 diabetic patients without (DAN-ve), and 34 with (DAN+ve) autonomic neuropathy. ECG samples were selected from previously recorded 24-h ECGs on the basis of a clearly defined T wave and a steady RR interval over 2 min of around 750 ms (80 beats min-1). There were no significant differences in RR interval between the groups. The two diabetic groups had slightly longer QT measurements (normal 365 +/- 14 (+/- SD) ms, DAN-ve 373 +/- 18 ms, DAN+ve 375 +/- 23 ms, p = 0.05), and corrected QT (QTc) values (normal 423 +/- 15 ms, DAN-ve 430 +/- 20 ms, DAN+ve 435 +/- 24 ms, p = 0.05). Ten diabetic patients fell above our defined upper limit of normal for QTc (greater than mean + 2SD). There was a significant correlation in the DAN-ve group between the QT indices and 24-h RR counts (QT r = -0.38, p less than 0.01; QTc r = -0.40, p less than 0.01). We conclude that there are some small alterations in QT interval length in the steady state in diabetic autonomic neuropathy. The changes appear to be due to autonomic impairment, rather than diabetes per se.
Ewing et al. (Mon,) conducted a cross-sectional in Diabetic autonomic neuropathy (n=111). Diabetes with or without autonomic neuropathy vs. Normal subjects was evaluated on Corrected QT (QTc) interval length (p=0.05). Diabetes with and without autonomic neuropathy was associated with slightly longer QTc intervals compared to normal subjects (435±24 ms and 430±20 ms vs 423±15 ms, p=0.05).