Prevalence of anti-GAD65 in Greek population with type II diabetes mellitus

M. Panagiotidou; P. Tsiotra; T. Economopoulos; S. A. Raptis; E. Hatziagelaki

doi:10.1055/s-2007-984776

Diabetologie und Stoffwechsel, Table of Contents

Prevalence of anti-GAD65 in Greek population with type II diabetes mellitus

M Panagiotidou ¹, P Tsiotra ², T Economopoulos ¹, SA Raptis ², E Hatziagelaki ¹

¹2nd Dept of Internal Medicine, Diabetes Center and Research Institute „ATTIKO“ University Hospital – Athens, Greece
²Hellenic National Diabetes Center

Abstract

Background and aims: Autoimmune destruction of pancreatic β-cells is the main cause of insulin deficiency in type I diabetes mellitus and in a number of patients with type II diabetes. The presence of markers such as GAD65 or IA2, before the development of overt disease, can identify patients at risk. The aim of this retrospective study was to evaluate the prevalence of GAD65 in the Greek type II diabetic population. Materials and methods: We examined 1225 diabetic patients divided in two groups depending on their GAD65 reactivity. Both groups (GADAb+ and GADAb-) were further subdivided according to their BMI (lean: BMI<25, overweight: BMI≥25). Serum GAD65 antibodies were detected by a commercial available RIA kit (Medipan Diagnostica). Fasting plasma c-peptide levels were also available. Results: in a cohort of 1225 diabetic patients, 358 were GADAb⁺ (29,22%) (age: 36,21±0,76 years, BMI: 24,64±0,24) and 867 GADAb^- (70.78%) (age: 40,23±0,57, BMI: 25,41±0,52). Duration of diabetes was significantly lower (p<0.01) in GADAb⁺ patients compared to GADAb^- (4,9±0,35years, 7,38±0,30years respectively). As far as transition time, from drug to insulin therapy, is concerned, was significantly lower in GADAb⁺ (lean or overweight), compared to GADAb^- (lean or overweight) group (Table). Fasting c-peptide levels were significant lower in GADAb⁺ compared to GADAb^- patients (Table). Interestingly, GAD65 titers were similar in GADAb+ patients, regardless of their BMI. Furthermore, fasting c-peptide levels were similar in GADAb+ (lean or overweight) patients and correlated reversely with GAD65 titers (p<0.006, r=–0,192).

* p<0,05 vs. GADAb⁺ -lean, § p<0,05 vs. GADAb⁺ -overweight, # p<0,003 vs. GADAb^- -lean
		AGE (years)	C-PEPTIDE (ng/ml)	BMI (Kgr/cm ² )	GAD titre (U/ml)	DURATION DISK- INS (years)
GADAb ⁺ n=358	LEAN	36,15±1,58	0,77±0,06	21,45±0,25	21,68±2,32	3,2±2,20
	OVERWEIGHT	36,27±2,26	0,77±0,14	27,82±0,84*	17,77±5,50*	2,58±0,90
GADAb ^- n=867	LEAN	38,45±2,54	2±0,20*§	21,87±0,26§	0,79±0,013*§	10,77±5,80
	OVERWEIGHT	42±1,99*§	2,4±0,23* §#	28,95±0,50*#	0,770,016* §	10,12±1,80*§

Conclusions: According to our results, measurement of GAD65 antibodies is highly recommended in all diabetic patients regardless of their BMI.