Metabolic syndrome in adult-onset latent autoimmune diabetes

Background. Latent autoimmune diabetes in adults (LADA) is characterized by islet beta-cell loss and absolute insulin deficiency, however, studies in recent years have shown some extent of insulin resistance in LADA patients. In view of insulin resistance being the central pathogenesis of metabolic syndrome (MS), we hypothesized that MS could be found in LADA patients. Methods. A total of 60 glutamic acid decarboxylase antibody (GAD-Ab)-positive LADA patients and 120 patients with type 2 diabetes (T2DM) were enrolled for the study. MS and its components were diagnosed according to the working definitions proposed by World Health Organization and National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III ATP III]). Insulin resistance and high sensitive C reactive protein (hsCRP) levels were also evaluated in patients with or without MS. Serum insulin and hsCRP levels were determined with radioimmune and immunoturbidimetric assays, respectively. Results. MS was found in 50% of LADA patients by WHO criteria and in 40% by ATP III criteria. The proportions of MS and its metabolic components were all comparable between LADA and T2DM patients except that a lower proportion of hypertension was seen in LADA. LADA patients with MS had significantly higher HOMA-IR index (0.85 +/- 0.33 vs. 0.60 +/- 0.26, p = 0.001 for WHO criteria; 0.89 +/- 0.34 vs. 0.62 +/- 0.26, p = 0.000 for ATP III criteria) and hsCRP levels (0.86 vs. 0.41, p = 0.019 for WHO criteria; 0.96 vs. 0.66, p = 0.018 for ATP III criteria) than LADA without MS patients. Conclusions. Our findings indicate that MS does exist in LADA patients, suggesting that the a diagnosis of MS could not exclude one of LADA and that insulin sensitizers may be beneficial in therapeutic strategies for treating these conditions.