A simple test for autonomic neuropathy in juvenile diabetics.

The reproducibility of a simple method for determining the beat-to-beat variation during maximal respiration (duration of inspiration = duration of expiration = 5 sec), using an ordinary ECG apparatus and a ruler, was tested in 10 normals and 40 insulin-treated diabetics. The results were reproducible and beat-to-beat variation was found to be independent of a 25-minute period of rest. The method was subsequently applied to 126 insulin-treated diabetics and the results are in accordance with previous investigations on cardiac vagal neuropathy. The method is applicable as a clinical routine test for cardiac vagal neuropathy.