The Relationship Between QT Intervals and Cardiac Autonomic Neuropathy in Nigerian Patients with Type 2 Diabetes Mellitus

Abstract

To study the pattern of QT intervals in Type 2 diabetic patients (T2DM) and investigate whether they have correlation with or predict development of Cardiac Autonomic Neuropathy (CAN). One hundred and eight (108) T2DM patients were compared with 88 normal controls. They all had resting ECG performed and QT intervals manually measured. The T2DM patients had non-invasve assessment of cardiac autonomic function. When more than two of the 6 tests was accepted as presence of CAN.Those with and without CAN were compared statistically and correlation determined. The QT intervals (QTc, QTd, QTcd) were significantly longer in patients than controls. Thirty seven(34.2%) of the patients had CAN. Their age and the QT intervals were not statistically different from those without CAN. The QTc was longer than 440msecs in 30 (27.8%) and QTcd longer than 80msecs in 13 (12.0%) of the study patients. About 46.7% of those whose QTc was longer than 440msecs and 54% whose QTcd were longer than 80msecs had CAN. These did not differ significantly from those without CAN. On regression analysis, none of the QT intervals correlated with or predicted CAN. There was also no correlation between QT intervals and control of blood sugar or duration of disease. The QT intervals were longer in patients than controls. There was no difference in QT intervals of patients with CAN and those without. The QT intervals did not correlate with or predict CAN

Keywords: keQt Intervals, Cardiac Autonomic Neuropathy, Type 2 Diabetic, Nigerian

Nigerian Medical Practitioner Vol. 53 (4) 2008: pp. 48-51