Carboxypeptidase-H autoantibodies differentiate a more latent subset of autoimmune diabetes from phenotypic type 2 diabetes among Chinese adults.
This study aimed to investigate whether carboxypeptidase-H antibody (CPH-Ab) can help identify latent autoimmune diabetes in adults (LADA). Phenotypic type 2 diabetic (T2D) patients (n= 1296) were studied for CPH Abs and autoantibodies to glutamic acid decarboxylase (GAD-Abs). CPH-Ab(+) T2D patients also underwent testing for insulinoma protein tyrosine phosphatase (IA-2A). Clinical features were compared among CPH-Ab(+), GAD-Ab(+), and Ab(-) T2D patients. Some of the antibody-positive patients were followed up for 3 years to assess beta cell function. The prevalence of CPH-Abs in T2D patients was 4.8%, significantly higher than that in controls. Double positivity was rare between CPH-Abs and GAD-Abs or IA-2A. Compared to patients with Ab(-) T2D, those with CPH-Ab(+) T2D had lower BMI, lower fasting C-peptide (FCP) levels, and more frequent ketosis, while not as much as did those with GAD-Ab(+) T2D. The mild beta cell dysfunction in patients with CPH-Ab(+) T2D was associated with their longer duration of diabetes. No marked change of C-peptide in the CPH-Ab(+) group was found during follow-up. These findings demonstrated that CPH-Abs may allow discrimination of a more latent subset of adult-onset autoimmune diabetes (LADA) whose features are intermediate between those with classic GAD-Ab(+) LADA and patients with Ab(-) T2D.
Yang
L
L
Diabetes Center, Institute of Metabolism and Endocrinology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
Zhou
Z G
ZG
Tan
S Z
SZ
Huang
G
G
Jin
P
P
Yan
X
X
Li
X
X
Peng
H
H
Hagopian
W
W
D000328:Adult; D017668:Age of Onset; D000368:Aged; D001323:Autoantibodies / Q000097:blood* / Q000502:physiology; D043423:Carboxypeptidase H / Q000276:immunology*; D016022:Case-Control Studies; D002681:China / Q000453:epidemiology; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology / Q000276:immunology; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology / Q000276:immunology; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007515:Islets of Langerhans / Q000502:physiology; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D016036:Seroepidemiologic Studies
D001323:Autoantibodies; D043423:Carboxypeptidase H