The value of islet cell antibody in predicting secondary failure of oral hypoglycaemic agent therapy in Diabetes mellitus.

The sera of 160 diabetics who were well controlled by oral hypoglycaemic agents (OHA) for at least three months after diagnosis were tested for pancreatic islet cell antibodies (ICAb) either at diagnosis or within two years after diagnosis. 129 were non-obese at diagnosis and of these ICAb was detected in the sera in 20 (16%). 31 were obese at diagnosis and of these ICAb was detected in the sera in three (10%). All of the 160 diabetics were insulin independent at the time of testing the serum for ICAb. The presence of ICAb was associated with a high probability of becoming insulin dependent, calculated from actuarial statistics. 86% of ICAb positive patients initially controlled on OHA may be expected to be insulin dependent at five years from diagnosis as compared to 18% of ICAb negative patients. Obesity at diagnosis did not significantly affect the probability of becoming insulin dependent. ICAb positive diabetes controlled by OHA can be regarded as a less severe form of insulin-dependent (Type I) diabetes.