BACKGROUND: Glycosylated hemoglobin (HbA1c) has been recommended as a diagnostic test for prediabetes and diabetes. Here, we evaluated the level of agreement between diagnoses based on fasting plasma glucose (FPG) versus HbA1c levels and determined optimal HbA1c cutoff values for these diseases in youth and young adults. METHODS: The study included 7,332 subjects (n=4,129, aged 10 to 19 years in youth group; and n=3,203 aged 20 to 29 years in young adult group) from the 2011 to 2016 Korea National Health and Nutrition Examination Survey. Prediabetes and diabetes were defined as 100 to 125 mg/dL (impaired fasting glucose [IFG]) and ≥126 mg/dL for FPG (diabetes mellitus [DM] by FPG [DMFPG]), and 5.7% to 6.4% and ≥6.5% for HbA1c, respectively. RESULTS: In the youth group, 32.5% with IFG had an HbA1c level of 5.7% to 6.4%, and 72.2% with DMFPG had an HbA1c ≥6.5%. In the young adult group, 27.5% with IFG had an HbA1c level of 5.7% to 6.4%, and 66.6% with DMFPG had an HbA1c ≥6.5%. Kappa coefficients for agreement between the FPG and HbA1c results were 0.12 for the youth group and 0.19 for the young adult group. In receiver operating characteristic curve analysis, the optimal HbA1c cutoff for IFG and DMFPG were 5.6% and 5.9% in youths and 5.5% and 5.8% in young adults, respectively. CONCLUSION: Usefulness of HbA1c for diagnosis of IFG and DMFPG in Koreans aged <30 years remains to be determined due to discrepancies between the results of glucose- and HbA1c-based tests. Additional testing might be warranted at lower HbA1c levels to detect IFG and DMFPG in this age group.
Adolescent ; Blood Glucose ; Diabetes Mellitus ; Diagnosis ; Diagnostic Tests, Routine ; Fasting ; Glucose ; Hemoglobin A, Glycosylated ; Humans ; Korea ; Nutrition Surveys ; Plasma ; Prediabetic State ; ROC Curve ; Young Adult

OBJECTIVES: This study analyzed Korea National Health and Nutrition Examination Survey data from 2007 to 2017 to assess trends in the prevalence, treatment, and control of diabetes in Korean adults ≥30 years of age. METHODS: Prevalent diabetes was defined as a fasting plasma glucose level ≥126 mg/dL, self-reported use of anti-diabetic treatment (insulin or oral anti-diabetic drugs), or diabetes diagnosis by a physician. Target levels were defined as glycosylated hemoglobin <6.5% or <7.0%, blood pressure <130/80 mmHg, and total cholesterol <200 mg/dL. All survey waves were age-standardized to the 2005 Korean census population. RESULTS: Diabetes prevalence increased from 9.6% in 2007–2009 to 10.8% in 2016-2017 (p<0.001). Impaired fasting glucose prevalence significantly increased in both genders and almost every age group. Diabetes awareness and glycemic control did not show an increasing trend; however, the treatment rate and proportion of people diagnosed with diabetes achieving target blood pressure and total cholesterol levels improved from 57.2% to 63.5% (p=0.008), from 41.1% to 53.2% (p<0.001), and from 65.0% to 78.0% (p<0.001), respectively. CONCLUSIONS: From 2007 to 2017, the prevalence of diabetes increased moderately in Korea, whereas the diabetes treatment rate and the proportion of people diagnosed with diabetes achieving target blood pressure and total cholesterol levels improved. However, awareness of diabetes and glycemic control require significant improvements. A national-level action plan is required to raise awareness about diabetes and prediabetes, with the goal of improving glycemic control and minimizing the occurrence of adverse health outcomes.
Adult ; Blood Glucose ; Blood Pressure ; Censuses ; Cholesterol ; Diabetes Mellitus ; Diagnosis ; Fasting ; Glucose ; Hemoglobin A, Glycosylated ; Humans ; Korea ; Nutrition Surveys ; Prediabetic State ; Prevalence

OBJECTIVES: This study analyzed Korea National Health and Nutrition Examination Survey data from 2007 to 2017 to assess trends in the prevalence, treatment, and control of diabetes in Korean adults ≥30 years of age.METHODS: Prevalent diabetes was defined as a fasting plasma glucose level ≥126 mg/dL, self-reported use of anti-diabetic treatment (insulin or oral anti-diabetic drugs), or diabetes diagnosis by a physician. Target levels were defined as glycosylated hemoglobin <6.5% or <7.0%, blood pressure <130/80 mmHg, and total cholesterol <200 mg/dL. All survey waves were age-standardized to the 2005 Korean census population.RESULTS: Diabetes prevalence increased from 9.6% in 2007–2009 to 10.8% in 2016-2017 (p<0.001). Impaired fasting glucose prevalence significantly increased in both genders and almost every age group. Diabetes awareness and glycemic control did not show an increasing trend; however, the treatment rate and proportion of people diagnosed with diabetes achieving target blood pressure and total cholesterol levels improved from 57.2% to 63.5% (p=0.008), from 41.1% to 53.2% (p<0.001), and from 65.0% to 78.0% (p<0.001), respectively.CONCLUSIONS: From 2007 to 2017, the prevalence of diabetes increased moderately in Korea, whereas the diabetes treatment rate and the proportion of people diagnosed with diabetes achieving target blood pressure and total cholesterol levels improved. However, awareness of diabetes and glycemic control require significant improvements. A national-level action plan is required to raise awareness about diabetes and prediabetes, with the goal of improving glycemic control and minimizing the occurrence of adverse health outcomes.
Adult ; Blood Glucose ; Blood Pressure ; Censuses ; Cholesterol ; Diabetes Mellitus ; Diagnosis ; Fasting ; Glucose ; Hemoglobin A, Glycosylated ; Humans ; Korea ; Nutrition Surveys ; Prediabetic State ; Prevalence

BACKGROUND: Previous studies have reported that fasting insulin and blood glucose levels are higher in postmenopausal than in premenopausal women and that insulin resistance was more serious in postmenopausal women. The effects of menopause on glucose metabolism have been well studied, but it is unclear whether age at menopause onset is associated with fasting blood sugar and HbA1c levels. The purpose of this study is to determine the effect of menopause age on diabetes and prediabetes.METHODS: We retrospectively analyzed data from the Sixth Korea National Health and Nutrition Examination Survey (2013–2015). The participants were 2,156 naturally menopausal women, except diabetes, stroke, coronary artery disease and cancer patients. The study population was divided into four groups according to the age of natural menopause onset ( < 40, 40–44, 45–55, and ≥56 years). Diagnosis of diabetes and prediabetes was based on the American Diabetes Association guideline. The association between menopause age and diabetes or prediabetes was analyzed by multiple logistic regression.RESULTS: Women reaching menopause at 40–44 years were 4.901 times more likely to have diabetes (odds ratio [OR], 4.901; 95% confidence interval [95% CI], 1.353–17.756, P=0.016) than those who reached menopause at an age of ≥56 years. Women with menopause at age < 40 years were 2.839 times more likely to have diabetes or prediabetes (OR, 2.839; 95% CI, 1.012–7.968, P=0.047).CONCLUSION: Women with premature menopause (< 40 years) have high risk of developing diabetes or prediabetes, and women with a menopause age of 40–44 years have high risk of developing diabetes.
Blood Glucose ; Coronary Artery Disease ; Diabetes Mellitus ; Diagnosis ; Fasting ; Female ; Glucose ; Humans ; Insulin ; Insulin Resistance ; Korea ; Logistic Models ; Menopause ; Menopause, Premature ; Metabolism ; Nutrition Surveys ; Prediabetic State ; Retrospective Studies ; Stroke

BACKGROUND: Oral glucose tolerance test (OGTT) is a traditional diagnostic tool for diabetes. Hemoglobin A1c (HbA1c) is an alternative method used in adults; however, its application in youths has been controversial. We evaluated the diagnostic performance of HbA1c and determined optimal cutoff points for detecting prediabetes and diabetes in youth. METHODS: This retrospective study included 389 obese children (217 boys, 55.8%) who had undergone simultaneous OGTT and HbA1c testing at six hospitals, Korea, between 2010 and 2016. Subjects were diagnosed with diabetes (fasting glucose ≥ 7.0 mmol/L; 2-hour glucose ≥ 11.1 mmol/L) or prediabetes (fasting glucose 5.6–6.9 mmol/L; 2-hour glucose 7.8–11.0 mmol/L). The diagnostic performance of HbA1c for prediabetes and diabetes was determined using the area under the receiver operating characteristic curve (AUC). RESULTS: At diagnosis, 197 (50.6%) subjects had normoglycemia, 121 (31.1%) had prediabetes, and 71 (18.3%) had diabetes. The kappa coefficient for agreement between OGTT and HbA1c was 0.464. The optimal HbA1c cutoff points were 5.8% (AUC, 0.795; a sensitivity of 64.1% and a specificity of 83.8%) for prediabetes and 6.2% (AUC, 0.972; a sensitivity of 91.5% and a specificity of 93.7%) for diabetes. When HbA1c (≥ 6.2%) and 2-hour glucose level were used to diagnose diabetes, 100% were detected. CONCLUSION: Pediatric criteria for HbA1c remain unclear, therefore, we recommend the combination of fasting and 2-hour glucose levels, in addition to HbA1c, in the diagnosis of childhood prediabetes and diabetes.
Adolescent* ; Adult ; Child* ; Diabetes Mellitus ; Diagnosis ; Fasting ; Glucose ; Glucose Tolerance Test* ; Humans ; Korea ; Methods ; Prediabetic State* ; Retrospective Studies ; ROC Curve ; Sensitivity and Specificity

Diabetic neuropathy is a complex and common disorder with multiple etiologies and affects about 43.1% of the Korean diabetes population. Good glycemic control slows progression of diabetic neuropathy in subjects with type 1 diabetes but seems to provide little benefit in subjects with type 2 diabetes. Moreover, neuropathy has been shown to develop in humans at stages of prediabetes and in the absence of overt hyperglycemia. Given the increasing incidence of both type 1 and type 2 diabetes and obesity and the impact of diabetic neuropathy on the quality of life of patients, a strategy for early diagnosis and discovery of an effective treatment is important for prevention and progression of diabetic neuropathy. Approximately 14.4% of Korean diabetics with neuropathy have associated pain, and management of this pain has been unsuccessful for many clinicians and patients. Choice of the correct drug(s), dosage, and patient management seems to be based on individualized conditions and needs. Overall, for good management and prevention for diabetic foot morbidities, early and proper diagnosis of diabetic neuropathy is essential, and simple and precise diagnostic methods must be developed.
Diabetic Foot ; Diabetic Neuropathies* ; Diagnosis ; Early Diagnosis ; Humans ; Hyperglycemia ; Incidence ; Obesity ; Pain Management ; Prediabetic State ; Quality of Life

BACKGROUND: This report presents the recent prevalence and comorbidities related to diabetes in Korea by analyzing the nationally representative data. METHODS: Using data from the Korea National Health and Nutrition Examination Survey for 2013 to 2014, the percentages and the total number of subjects over the age of 30 years with diabetes and prediabetes were estimated and applied to the National Population Census in 2014. Diagnosis of diabetes was based on fasting plasma glucose (≥126 mg/dL), current taking of antidiabetic medication, history of previous diabetes, or glycosylated hemoglobin (HbA1c) ≥6.5%. Impaired fasting glucose (IFG) was defined by fasting plasma glucose in the range of 100 to 125 mg/dL among those without diabetes. RESULTS: About 4.8 million (13.7%) Korean adults (≥30 years old) had diabetes, and about 8.3 million (24.8%) Korean adults had IFG. However, 29.3% of the subjects with diabetes are not aware of their condition. Of the subjects with diabetes, 48.6% and 54.7% were obese and hypertensive, respectively, and 31.6% had hypercholesterolemia. Although most subjects with diabetes (89.1%) were under medical treatment, and mostly being treated with oral hypoglycemic agents (80.2%), 10.8% have remained untreated. With respect to overall glycemic control, 43.5% reached the target of HbA1c < 7%, whereas 23.3% reached the target when the standard was set to HbA1c < 6.5%, according to the Korean Diabetes Association guideline. CONCLUSION: Diabetes is a major public health threat in Korea, but a significant proportion of adults were not controlling their illness. We need comprehensive approaches to overcome the upcoming diabetes-related disease burden in Korea.
Adult ; Blood Glucose ; Censuses ; Comorbidity ; Diabetes Mellitus ; Diagnosis ; Fasting ; Glucose ; Hemoglobin A, Glycosylated ; Humans ; Hypercholesterolemia ; Hypoglycemic Agents ; Korea* ; Nutrition Surveys ; Prediabetic State ; Prevalence ; Public Health ; Republic of Korea

We aimed to estimate the threshold level of glycosylated hemoglobin (HbA1c) for the fasting plasma glucose of 100 and 126 mg/dL in the Korean adult population, using the 2011 Korea National Health and Nutrition Examination Survey. A total of 4,481 participants over 19 years of age without diabetic medications and conditions to influence the interpretation of HbA1c levels, such as anemia, renal insufficiency, liver cirrhosis, and cancers, were analyzed. A point-wise area under the receiver operating characteristic curve was used to estimate the optimal HbA1c cutoff value. A HbA1c threshold of 6.35% was optimal for predicting diabetes with a sensitivity of 86.9% and a specificity of 99.1%. Furthermore, the threshold of HbA1c was 5.65% for prediabetes, with a sensitivity of 69.3% and a specificity of 71%. Further prospective studies are needed to evaluate the HbA1c cutoff point for diagnosing prediabetes and diabetes in the Korean population.
Adult ; Anemia ; Blood Glucose ; Diabetes Mellitus ; Diagnosis ; Fasting ; Hemoglobin A ; Hemoglobin A, Glycosylated* ; Humans ; Korea* ; Liver Cirrhosis ; Nutrition Surveys* ; Prediabetic State* ; Prospective Studies ; Renal Insufficiency ; ROC Curve ; Sensitivity and Specificity

BACKGROUND: We evaluated the diagnostic rate of diabetes using fasting plasma glucose (FPG), 2-hour plasma glucose (2h PG) after 75 g oral glucose tolerance test (OGTT), and glycosylated hemoglobin (HbA1c) levels, and we elucidated the pathophysiologic characteristics and risk factors that give rise to diabetes in patients with prediabetes. METHODS: The data of 236 patients who had the OGTT at Konkuk University Hospital were analyzed. Fasting, 30, and 120 minutes blood glucose levels and insulin levels were measured. The diagnostic rate of diabetes was assessed using FPG, 2h PG, and HbA1c levels. The clinical data and insulin resistance and secretion evaluations were compared using indexes according to the fasting glucose level. RESULTS: Among 236 subjects, 97 (41.1%) were diabetics and 102 (43.2%) were prediabetics. The rate of diabetes diagnosis by one of the individual criteria was 56.7%, 53.6%, and 84.5% for FPG, HbA1c, and 2h PG, respectively. When two criteria were used to diagnose diabetes, 72.2% of the diabetic patients were identified by FPG and HbA1c, while 100% were identified by FPG and 2h PG, and 91.7% were identified by 2h PG and HbA1c. The HbA1c cut-off value for 2h PG ≥200 mg/dL was 6.1%, and the FPG cut-off value was 115 mg/dL. In impaired fasting glucose subjects, the HbA1c level, Matsuda index, and insulinogenic index were associated with risk of occurrence of overt diabetes (P<0.01). CONCLUSION: This study suggests that performing additional OGTT for patients with FPG ≥110 mg/dL or HbA1c ≥6.1% is helpful to reclassify their glucose tolerance status and evaluate their potential for progressing to overt diabetes.
Blood Glucose ; Diabetes Mellitus* ; Diagnosis ; Fasting ; Glucose ; Glucose Tolerance Test* ; Hemoglobin A, Glycosylated ; Humans ; Insulin ; Insulin Resistance ; Prediabetic State ; Risk Factors

The aim of this study was to compare the fasting serum glucose level with the fasting plasma glucose level for diagnosing hyperglycemic states in real-life clinical situations. Additionally, we investigated a usual delay in sample processing and how such delays can impact the diagnosis of hyperglycemic states. Among 1,254 participants who had normoglycemia or impaired fasting glucose (IFG) assessed by the fasting serum glucose level, 20.9% were newly diagnosed with diabetes based on the plasma fasting glucose level. Of the participants with normoglycemia, 62.1% and 14.2% were newly diagnosed with IFG and diabetes, respectively, according to the plasma fasting glucose level. In our clinical laboratory for performing health examinations, the time delay from blood sampling to glycemic testing averaged 78±52 minutes. These findings show that the ordinary time delay for sample processing of the serum glucose for screening hyperglycemic states may be an important reason for these diagnoses to be underestimated in Korea.
Blood Glucose* ; Diagnosis* ; Fasting ; Glucose ; Korea ; Mass Screening* ; Plasma ; Prediabetic State*