[Relation between insulin resistance and glutamic acid decarboxylase antibody titers in latent autoimmune diabetes in adults].
OBJECTIVE
To investigate the relation between insulin resistance and glutamic acid decarboxylase antibody (GAD-Ab) titers in latent autoimmune diabetes in adults (LADA).


METHODS
The patients with phenotypic type 2 diabetes were screened for GAD-Ab positivity, and the 141 positive patients were divided into two subgroups according to the GAD-Ab titer, namely the high-titer group (LADA-1 subtype) and low-titer group (LADA-2 subgroup). The clinical features and insulin resistance were compared between the two groups. Insulin resistance was calculated by HOMA 2 software, and GAD-Ab and C peptide were determined with radioligand and radioimmune assay, respectively.


RESULTS
Compared with low-titer LADA patients, the patients with high titers had younger age of onset, lower BMI, higher HbA1c level, and worse fasting and postprandial C peptide levels. The insulin resistance index by HOMA 2 was significantly lower in LADA-1 group than in LADA-2 group (1.6-/+1.1 vs 2.1-/+1.1, P=0.001). The HOMA2-IR index showed a negative correlation to GAD-Ab titer.


CONCLUSIONS
The degree of insulin resistance is correlated to GAD-Ab titers in LADA, and low titer patients have higher insulin resistance level.
Li
Xia
X
Second Xiangya Hospital, Diabetes Center, Institute of Metabolism and Endocrinology, Central South University, Changsha 410011, China. hellolxwj@yahoo.com.cn
Huang
Gan
G
Yan
Xiang
X
Yang
Lin
L
Zhou
Zhi-guang
ZG
D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood*; D001327:Autoimmune Diseases / Q000175:diagnosis / Q000276:immunology*; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis / Q000276:immunology*; D005260:Female; D005968:Glutamate Decarboxylase / Q000276:immunology*; D006801:Humans; D007333:Insulin Resistance; D007515:Islets of Langerhans / Q000276:immunology / Q000502:physiology; D008297:Male; D008875:Middle Aged
D001323:Autoantibodies; D005968:Glutamate Decarboxylase