Prevalence and Characteristics of Metabolically Obese but Normal Weight and Metabolically Healthy but Obese in Middle-aged Koreans: the Chungju Metabolic Disease Cohort (CMC) Study

BACKGROUND: We attempted to determine the prevalence and characteristics of metabolically obese but normal weight (MONW) and metabolically healthy but obese (MHO) individuals in a large cohort of middle-aged Koreans. METHODS: 8,987 non-diabetic subjects were selected from the Chungju Metabolic disease Cohort Study performed in 2003-2006. MONW was defined as a body mass index (BMI) > or = 18.5 and or = 25 kg/m2 with HOMA-IR in the lowest quartile. RESULTS: The mean age of the subjects was 62.3 +/- 10.5 years (men 40.4%). The age-adjusted prevalence of MONW and MHO were 4.3% (5.3% men, 3.7% women) and 5.6% (3.6% men, 7.0% women), respectively. 14.2% of men and 12.9% of women were classified as MONW among the normal weight population, whereas 10.7% of men and 14.5% of women were classified as MHO among the obese subjects. The prevalence of prediabetes was significantly higher in the MONW group than in the MHO group (34.7 vs. 12.5%, P < 0.0001 in men; 23.1 vs. 8.8%, P < 0.0001 in women). The MONW group evidenced an equivalent risk of coronary heart disease (CHD) relative to the MHO group (10.77 +/- 0.68 vs. 10.22 +/- 0.90% in men; 7.02 +/- 0.34 vs. 7.26 +/- 0.26% in women, means +/- standard error [SE]). CONCLUSION: The subjects in the MONW group are characterized by a high risk of diabetes and CHD, despite their normal weights. Their substantial prevalence in the population emphasizes the importance of identifying subjects in the MONW group, and warrants more intensive risk management.

Factors Associated with Insulin Resistance in a Middle-Aged Non-Obese Rural Population: The Chungju Metabolic Disease Cohort (CMC) Study / 한국역학회지

OBJECTIVES: We aimed to determine the characteristics affecting insulin resistance in non-obese middle-aged adults in a rural community. METHODS: A total of 1,270 non-diabetic adults aged between 40 and 64 years old with body mass index (BMI) less than 25 kg/m2 were analyzed. Subjects with insulin resistance were defined as those who had the highest quartile value of the homeostasis model assessment of insulin resistance (HOMA-IR) in a non-diabetic population. RESULTS: A total of 217 subjects (20.6%) had insulin resistance. Prevalence of metabolic syndrome was significantly higher in insulin-resistant subjects in both men (29.3% vs. 10.3%) and women (34.1% vs. 15.6%). Among metabolic syndrome components, elevated waist circumference and elevated triglyceride were higher in insulin-resistant subjects in both genders. After being controlled for socioeconomic status and lifestyle related covariates, the association between insulin resistance and BMI was statistically significant in the category of 23.0-24.9 kg/m2 in men (adjusted OR, 4.63; 95% confidence interval [95% CI], 1.77-12.15) using the category of 18.5-20.9 kg/m2 as a reference. In addition, the association between insulin resistance and abdominal obesity was statistically significant only for men (adjusted OR, 2.57; 95% CI, 1.29-5.11). CONCLUSION: Insulin resistance appears to be highly associated with high BMI and abdominal obesity, even in non-obese, non-diabetic middle-aged men.

Association between Metabolic Syndrome and Alcohol drinking and Smoking histories in a rural area of Korea / 한국역학회지

PURPOSE: Prevalence of metabolic syndrome is increasing markedly in rural area of Korea. Alcohol drinking and smoking are the main risk factors which shows the highest prevalence rate among the risk factors of metabolic syndrome. The aim of this study was to investigate the association between metabolic syndrome and alcohol drinking and smoking histories in a rural area of Korea. METHODS: Data was obtained from 1,332(507 men, 825 women) individuals aged over 40 years who lived in rural area of Chungju city in 2007. Metabolic syndrome was defined by NCEP ATP III criteria and waist circumference was defined by WHO-APR(Asia Pacific Region). Data analysis was carried out using SAS version 8.02. RESULTS: In men, adjusted odds ratio for metabolic syndrome was 2.78(1.09-7.05) for current alcohol drinker, 2.75(1.38-5.51) for past alcohol drinker, 3.25(1.58-6.67) for under 21 years old at start of alcohol drinking, 2.62(1.12-6.11) for light alcohol drinker, 6.01(2.65-13.64) for heavy alcohol drinker. In women, all the alcohol related risk factors were not statistically significant with metabolic syndrome. For all the smoking related risk factors were not statistically significant with metabolic syndrome in men and women. Adjusted odds ratio of alcohol drinking habits for each components of diagnostic criteria of metabolic syndrome was significant for high blood pressure, high fasting glucose and hypertriglyceridemia in men and abdominal obesity in women. Adjusted odds ratio of cigarette smoking habits for each components of diagnostic criteria of metabolic syndrome was significant for abdominal obesity in women. CONCLUSION: Controlling alcohol drinking habits in men should be reinforced in order to prevent the metabolic syndrome in a rural area of Korea.