Prevalence of glutamic acid decarboxylase antibodies amongst young Malaysian diabetics.
This study determined the prevalence of glutamic acid decarboxylase antibodies (GAD Ab) in a group of 926 young Malaysian diabetics of three ethnic groups, Malay, Chinese, and Indian. Patients were clinically diagnosed to be Type 1 or Type 2 before the age of 40 years. The overall GAD Ab positivity was 17.4% (161/926), significantly higher in the Type 1 than the Type 2 diabetics (35.5%, 116/329 vs. 7.5%, 45/597, P=0.0001). Compared to GAD Ab negative patients, seropositive diabetics were diagnosed at younger age (21.2+/-0.9 vs. 27.4+/-0.3 y, P=0.0001), had lower fasting (289+/-27.4 vs. 640+/-17.6 pmol/l, P=0.0001) and post-glucagon C-peptide levels (527+/-51.8 vs. 1030+/-28.9 pmol/l, P=0.0001). There were no racial differences in the prevalence of GAD Ab; of the total Type 1, 30.8, 36.4, and 39.4% were Malay, Chinese, and Indian diabetics, respectively and of the total Type 2, 8.8, 8.2, and 4.4% were Malay, Chinese, and Indian diabetics respectively. There was a curvilinear relationship between GAD Ab and the post-glucagon C-peptide levels, suggesting that GAD Ab do play a role in the beta-cells destruction and could be an important immune marker for the LADA group. This study reconfirmed previous reports that the autoimmune mechanisms in the Type 1 Asian diabetics are indeed different from the Caucasians, and further investigations should be carried out to explain the differences.
Wan Nazaimoon
W M
WM
Division of Endocrinology, Institute for Medical Research, Jalan Pahang, Kuala Lumpur, Malaysia. nazaimon@imr.gov.my
Faridah
I
I
Singaraveloo
M
M
Ismail
I S
IS
Wan Mohamad
W B
WB
Letchuman
R
R
Rasat
R
R
Pendek
R
R
Hew
F L
FL
Sheriff
I H
IH
Khalid
B A
BA
D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D000906:Antibodies / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D002681:China / Q000208:ethnology; D003920:Diabetes Mellitus / Q000453:epidemiology / Q000208:ethnology / Q000276:immunology*; D005260:Female; D005968:Glutamate Decarboxylase / Q000276:immunology*; D006801:Humans; D007194:India / Q000208:ethnology; D007223:Infant; D008296:Malaysia / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D016036:Seroepidemiologic Studies
D000906:Antibodies; D005968:Glutamate Decarboxylase