QT dispersion and autonomic function in diabetic and non-diabetic patients with renal failure.

We have studied 13 patients with diabetic nephropathy and 13 patients with uraemia of other origin undergoing renal transplantation, and 12 control patients undergoing general surgery. QTc dispersion and maximum QTc interval were calculated from the 12-lead ECG, and cardiovascular autonomic function tests were performed. QTc dispersion was significantly greater in diabetic (mean 100 (SD 37) ms) and non-diabetic (51 (17) ms) uraemic patients than in control patients (29 (10) ms), and it differentiated the groups better than maximum QTc. In diabetic patients, severe autonomic neuropathy was common. In other uraemic patients less severe disturbances in autonomic function were found. In diabetic uraemic patients, increased QTc dispersion and severe autonomic neuropathy may indicate high risk for cardiac arrhythmias. In our opinion, QTc dispersion and autonomic function tests may give valuable information on perioperative risks.