成人隐匿型自身免疫糖尿病（LADA）是一种特殊类型的成人糖尿病，具有胰岛自身抗体阳性，初诊后至少半年不依赖胰岛素治疗，胰岛功能进行性衰退等特征。它是由T细胞介导的胰岛β细胞缓慢破坏的1型糖尿病亚型，初期临床表现与2型糖尿病相似，呈隐匿性发病，不需要胰岛素治疗，但胰岛功能呈进行性衰退，最终导致胰岛功能丧失。在相关人群中研究显示LADA患病人数占所有2型糖尿病患者的2%至20%。在韩国，绝大多数LADA患病率的研究在已经检测过GADA的糖尿病患者中进行，这样难以排除选择性偏差。本研究研究了新诊2型糖尿病成年患者中的LADA患病率和临床特征。
本研究样本来自病程5年内的新诊2型糖尿病患者，共462例。检测指标包括：GADA滴度、空腹胰岛素水平、空腹C肽水平、空腹血糖水平、糖化血红蛋白、以及血脂等指标，并同时采集临床病史资料。
研究发现，在所有462例初诊2型糖尿病患者中，共确诊20例LADA，患病率为4.3%。与GADA阴性患者相比，GADA阳性患者空腹C肽水平明显降低（1.2±0.8 ng/mL vs. 2.0±1.2 ng/mL, P=0.004）。其他检测指标在GADA阴性和阳性患者之间无明显统计学差异。
所以，本研究认为，韩国新诊断成年2型糖尿病患者中LADA患病率为4.3%。韩国GADA阳性患者所占新诊断2型糖尿病患者中的比例与日本相当，但低于中国及西方国家。韩国LADA患者空腹C肽水平较GADA阴性2型糖尿病患者低，表明胰岛分泌胰岛素功能下降。而LADA患者的空腹胰岛素水平、空腹血糖水平、糖化血红蛋白、血脂等指标与2型糖尿病患者无明显差异。

 Prevalence and Clinical Characteristics of Recently Diagnosed Type 2 Diabetes Patients with Positive Anti- Glutamic Acid Decarboxylase Antibody

Background: Latent autoimmune diabetes in adults (LADA) refers to a specific type of diabetes characterized by adult onset, presence of islet auto-antibodies, insulin independence at the time of diagnosis, and rapid decline in β-cell function. The prevalence of LADA among patients with type 2 diabetes varies from 2% to 20% according to the study population. Since most studies on the prevalence of LADA performed in Korea were conducted in patients who had been tested for anti-glutamic acid decarboxylase antibody (GADAb), a selection bias could not be excluded. In this study, we examined the prevalence and clinical characteristics of LADA among adult patients recently diagnosed with type 2 diabetes.
Methods: We included 462 patients who were diagnosed with type 2 diabetes within 5 years from the time this study was performed. We measured GADAb, fasting insulin level, fasting C-peptide level, fasting plasma glucose level, HbA1c, and serum lipid profiles and collected data on clinical characteristics.
Results: The prevalence of LADA was 4.3% (20/462) among adult patients with newly diagnosed type 2 diabetes. Compared with the GADAb-negative patients, the GADAb-positive patients had lower fasting C-peptide levels (1.2±0.8 ng/mL vs. 2.0±1.2 ng/mL, P=0.004). Other metabolic features were not significantly different between the two groups.
Conclusion: The prevalence of LADA is 4.3% among Korean adult patients with recently diagnosed type 2 diabetes. The Korean LADA patients exhibited decreased insulin secretory capacity as reflected by lower C-peptide levels.
链接: http://dx.doi.org/10.4093/dmj.2012.36.2.136