466 © 2005 Diabetes UK. Diabetic Medicine, 22, 466– 469 Introduction Diabetic ketoacidosis (DKA) is one of the most common and serious acute complications of diabetes, and is a significant cause of morbidity and mortality. In Western countries, the annual incidence rate of DKA estimated from population-based studies ranges from 4.6 – 8 episodes per 1000 diabetic patients [1,2]. According to previ- ous studies, DKA is present in 7.6% of admissions to intensive care and the mortality rate varies from less than 5% to 13% [3,4]. Clinical outcomes of DKA are influenced by the initial biochemical data and manifestations such as fever and severe coexisting illness [3,5]. In general, the common precipitating factors include infections, treatment non-compliance and con- comitant cardiovascular disease [5,6]. In Korea, the incidence of Type 1 diabetes mellitus is very low [7,8], whereas Type 2 diabetes mellitus has increased remarkably since the 1970s and 1980s [9,10]. Approximately 65% of Type 2 diabetic subjects are lean when overweight is defined as a body mass index (BMI) > 25 kg /m 2 [11]. Further- more, a recent report on the pathogenesis of Korean patients with Type 2 diabetes suggests that impaired insulin secretion is more prominent than insulin resistance, even at the impaired glucose tolerance stage [12]. Therefore, the clinical characteristics of DKA in Korea are likely to be somewhat different from those in Western countries. It is worth mentioning that Maldoado et al. [13] recently characterized ketosis-prone Type 2 diabetes. In addition, many socioeconomic changes have taken place since the 1980s, such as a rapidly Westernized life style, an explosive increase in the number of obese subjects and diabetic patients, and increased access to medical services. These environmental factors may have influenced the manifestations of DKA. Thus, the aim of this study was to investigate trends or changes in the clinical characteristics of DKA, including the Correspondence to: Ki-Ho Song, MD, Department of Internal Medicine, St. Vincent Hospital, 93 Chi-Dong, Paldal-Ku, Suwon, Korea. E-mail: kihos@vincent.cuk.ac.kr Abstract Aims The aim of this study was to investigate changes in the clinical character- istics of diabetic ketoacidosis (DKA) in Korea over the last two decades. Methods A retrospective medical record review of all episodes of DKA from 1982 to 2002 in four University-affiliated urban hospitals in Korea was per- formed. A total of 255 episodes of DKA (217 patients) were identified and divided into three consecutive 7-year periods to compare trends over time. Clinical characteristics including precipitating factors and hospital mortality were analyzed. Results A dramatic increase in DKA admissions has occurred over the last two decades, accompanied by a marked increase in admissions of diabetic patients. The clinical characteristics of DKA remained constant over the observation period. Non-compliance to treatment was the most common precipitating factor of DKA. A total of 30 patients died in hospital (11.8% of all episodes). Older age and infection appeared to influence mortality. Conclusions Our results suggest that rapidly increasing episodes of DKA in Korea, in parallel with increases in the numbers of diabetic patients, continue to be associated with significant mortality. Diabet. Med. 22, 466– 469 (2005) Keywords diabetic ketoacidosis, mortality, precipitating factors Blackwell Publishing, Ltd. Oxford, UK DME Diabetic Medicine 0742-3071 Blackwell Publishing, 2004 21 Original Article Original article Diabetic ketoacidosis in Korea, S-H. Ko et al. Clinical characteristics of diabetic ketoacidosis in Korea over the past two decades S-H. Ko*, W-Y. Lee†, J-H. Lee‡, H-S. Kwon*, J-M. Lee*, S-R. Kim*, S-D. Moon*, K-H. Song*, J-H. Han*, Y-B. Ahn*, S-J. Yoo* and H-Y. Son* *Department of Internal Medicine, The Catholic University of Korea, †Department of Internal Medicine, Sungkyunkwan University School of Medicine, and ‡Department of Preventive Medicine, The Catholic University of Korea, Seoul, Korea Accepted 25 May 2004