Clinical characteristics in the discrimination between patients with low or high C-peptide level among middle-aged insulin-treated diabetics.

We compared sensitivity, specificity and accuracy of selected clinical characteristics (age at diagnosis, initiation of permanent insulin therapy from diagnosis and degree of obesity) in the discrimination between diabetics with low or high fasting or post-glucagon C-peptide level in a population of 171 middle-aged insulin-treated diabetics (81 men, 90 women) living in East Finland. Individual clinical criteria were poor discriminators alone but their combinations gave high specificity for the low and high fasting and post-glucagon C-peptide classes. The specificity and the accuracy of combined criteria seemed to be somewhat higher among male than among female insulin-treated diabetics. The association between clinical characteristics and fasting or postglucagon C-peptide classes seemed to be similar.