Katulanda P, Shine B, Katulanda G W, Silva A, Asfir E L, Sheriff R, Somasundaram N, Long A E, Bingley P J, McCarthy M I, Clark A, Matthews D R
Oxford Centre for Diabetes, Endocrinology and Metabolism, Churchill Hospital, Old Road, Headington, Oxford, OX3 7LJ, UK.
Diabetologia. 2008 Aug;51(8):1368-74. doi: 10.1007/s00125-008-1052-6. Epub 2008 Jun 5.
AIMS/HYPOTHESIS: Diabetes mellitus is increasing among young adult South Asians. The aim of this study was to determine the prevalence and phenotypic characteristics of diabetes subtypes based on GAD65 autoantibody (GADA) status in those with young adult-onset diabetes in Sri Lanka.
Clinical, metabolic and GADA data were available for 992 consecutively recruited individuals with diabetes aged < or =45 years (age at diagnosis 16-40 years). Participants were classified according to the following definitions: type 1 diabetes, insulin-dependent <6 months from diagnosis; latent autoimmune diabetes in adults (LADA), GADA-positive, age > or =30 years and insulin-independent > or =6 months from diagnosis; type 2 diabetes, GADA-negative and insulin-independent > or =6 months from diagnosis.
The median (interquartile range) age at diagnosis and diabetes duration were 33.0 (29.0-36.1) and 4.0 (1.1-7.1) years, respectively; 42.1% were male. GADA positivity was seen in 5.4% of participants (n = 54) and GADA levels negatively correlated with age at diagnosis (p < 0.0001), BMI (p < 0.0001) and time to insulin requirement (p = 0.006). Type 1 diabetes, type 2 diabetes and LADA were present in 7.0%, 89.7% and 2.6%, respectively. The remaining 0.7% of the participants were GADA-positive, insulin independent > or =6 months from diagnosis and were diagnosed at age <30 years. The metabolic syndrome and homeostasis model assessment of beta cell function (HOMA %B) were lowest in GADA-positive type 1 diabetes and increased progressively in latent autoimmune diabetes, GADA-negative type 1 diabetes and type 2 diabetes. Among those requiring insulin, 69.2% had fasting C-peptide levels in the lowest quartile, whereas only 19.5% were GADA-positive (p < 0.0001).
CONCLUSIONS/INTERPRETATION: The prevalence of GADA-positive autoimmune diabetes is low among individuals with young adult-onset diabetes in Sri Lanka. Young-onset diabetic phenotypes appear as a continuum from autoimmune type 1 diabetes to type 2 diabetes.
目的/假设：在南亚年轻成年人中，糖尿病发病率正在上升。本研究旨在确定斯里兰卡年轻成人发病型糖尿病患者中基于谷氨酸脱羧酶65自身抗体（GADA）状态的糖尿病亚型患病率及表型特征。
收集了992例年龄≤45岁（诊断时年龄16 - 40岁）的糖尿病患者的临床、代谢及GADA数据。参与者根据以下定义分类：1型糖尿病，诊断后6个月内依赖胰岛素；成人隐匿性自身免疫性糖尿病（LADA），GADA阳性，年龄≥30岁且诊断后6个月以上不依赖胰岛素；2型糖尿病，GADA阴性且诊断后6个月以上不依赖胰岛素。
诊断时的中位（四分位间距）年龄和糖尿病病程分别为33.0（29.0 - 36.1）岁和4.0（1.1 - 7.1）年；42.1%为男性。5.4%的参与者（n = 54）GADA呈阳性，GADA水平与诊断时年龄（p < 0.0001）、BMI（p < 0.0001）及开始需要胰岛素的时间（p = 0.006）呈负相关。1型糖尿病、2型糖尿病和LADA的患病率分别为7.0%、89.7%和2.6%。其余0.7%的参与者GADA阳性，诊断后6个月以上不依赖胰岛素且诊断时年龄<30岁。代谢综合征和β细胞功能的稳态模型评估（HOMA %B）在GADA阳性的1型糖尿病中最低，在隐匿性自身免疫性糖尿病、GADA阴性的1型糖尿病和2型糖尿病中逐渐升高。在需要胰岛素治疗的患者中，69.2%的患者空腹C肽水平处于最低四分位数，而只有19.5%的患者GADA呈阳性（p < 0.0001）。
结论/解读：在斯里兰卡年轻成人发病型糖尿病患者中，GADA阳性自身免疫性糖尿病的患病率较低。年轻发病的糖尿病表型呈现出从自身免疫性1型糖尿病到2型糖尿病的连续谱。
