Antibodies to glutamic acid decarboxylase as predictors of insulin-dependent diabetes mellitus before clinical onset of disease

• Published in: The Lancet (British edition) 1994-06, Vol.343 (8910), p.1383-1385
• Main Authors: Tuomilehto, J., Vidgren, G., Toivanen, L., Tuomilehto-Wolf, E., Kohtamaki, K., Stengård, J., Zimmet, P., Mackay, I.R., Rowley, Mj, Koskela, P.
• Format: Article
• Language: English
• Subjects: Adult; Antibodies; Autoantibodies - blood; Biological and medical sciences; Biomarkers - blood; Diabetes; Diabetes mellitus; Diabetes mellitus (insulin dependent); Diabetes mellitus (non-insulin dependent); Diabetes Mellitus, Type 1 - diagnosis; Diabetes Mellitus, Type 1 - immunology; Diabetes Mellitus, Type 2 - immunology; Diabetes, Gestational - immunology; Diabetes. Impaired glucose tolerance; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Female; Glucose; Glutamate decarboxylase; Glutamate Decarboxylase - immunology; Glutamic acid; Humans; Insulin; Medical research; Medical sciences; Predictive Value of Tests; Pregnancy; Sensitivity and Specificity
• ISSN: 0140-6736; 1474-547X
• DOI: 10.1016/S0140-6736(94)92521-6

We have done a study designed to ascertain the effectiveness of measuring antibodies to glutamic acid decarboxylase (anti-GAD) in predicting insulin-dependent diabetes mellitus (IDDM). Anti-GAD was measured in prediabetic sera from 151 women aged 20-39 years with newly diagnosed diabetes mellitus who had been identified through a nationwide diabetes register. Multiple serum samples had been collected from these women up to 10 years before the clinical onset of diabetes during their earlier pregnancies. Anti-GAD was measured with a radioimmunoprecipitation assay. Anti-GAD was detected in 82% of 28 women with IDDM, in 36% of 11 women with non-insulin-dependent diabetes mellitus, and in 5% of 112 women with gestational diabetes mellitus. In a random sample of 100 non-diabetic young Finnish women, none had anti-GAD. The sensitivity of the anti-GAD assay for predicting IDDM was 82 1% and the specificity was 100%. The longest time of anti-GAD positivity before clinical onset of IDDM was 10 years. Once positive, anti-GAD levels remained stable and no patients became negative after a positive test during the prediabetic period. Anti-GAD is a valuable early predictive marker and is associated with a very high risk for development of IDDM.