Sex differences in factors associated with metabolic syndrome among Korean adults without diabetes mellitus: Results from the Korea National Health and Nutrition Examination Survey from 2010 to 2013

Objectives The purpose of this study was to examine sex differences in factors associated with metabolic syndrome in Korean adults without diabetes mellitus. Study design Cross-sectional design. Methods The dataset of Korea National Health and Nutrition Examination Survey from 2010 to 2013 was used. Among a total of 33552 adults aged ≥30, subjects who (i) were diagnosed or had been treated for diabetes mellitus, (ii) had a fasting blood glucose level of 126 mg/dL or higher or (iii) had a glycosylated haemoglobin level of 6.5% or higher were excluded. Subjects who had anaemia or were pregnant were also excluded. Finally, 9406 subjects were included in this study. Sex differences in subjects' characteristics were assessed with Student's t-test and chi-square test. Logistic regressions were used to examine factors associated with metabolic syndrome by sex. Results The prevalence of metabolic syndrome in Korean adults overall without diabetes mellitus was 12.2%. Glycosylated haemoglobin from 5.7 to 6.5 and increased body mass index were independently associated with metabolic syndrome in both men and women. Current smoking, age and age square were significantly associated with metabolic syndrome in men, whereas age and illiteracy were significantly associated with it in women. Conclusions This study confirmed that glycosylated haemoglobin and body mass index can be important indicators of metabolic syndrome in Korean adults without diabetes mellitus.