The relationship between high blood glucose and socio-economic position in childhood and adulthood in Korea: findings from the Korean National Health and Nutrition Examination, 2007-09

Abstract

Background Unlike the older birth cohort (1943-65), the younger birth cohort (1966-79) has enjoyed much improved standards with dramatic developments in Korea. This article investigated the relationship between socio-economic position (SEP) and risk of high blood glucose, including impaired fasting glucose (IFG) and type 2 diabetes mellitus (T2D) by birth cohort. Methods Of the 11 830 persons, 9792 persons aged 30-64 years participated in National Health and Nutrition Examination Surveys. We categorized four SEP groups based on education level in childhood and adulthood within two birth cohorts. High blood glucose included IFG (n = 2594) and T2D (n = 738). Odds ratio (OR) and 95% confidence interval (CI) were estimated by logistic regression. Results There was a significantly higher risk of high blood glucose in the younger cohort than in the older cohort. In the younger cohort, the ORs for males of declining SEP and of stable low SEP were OR: 1.50 (95% CI 1.12-2.00) and OR: 1.45 (95% CI 1.08-1.93), respectively. After adjustments, corresponding ORs were 1.47 (95% CI 1.09-1.98) and 1.54 (95% CI 1.14-2.08), respectively. In younger women, the corresponding ORs were 1.68 (95% CI 1.17-2.41) and 1.87 (95% CI 1.30-2.69), respectively; however, obesity attenuated the former relationship. For women in the older cohort, this inverse relationship was found only among those with a stable low SEP (OR 1.31, 95% CI 1.04-1.66); no significance was found after adjustments. There was no significant inverse relationship in the older cohort for men. Conclusions The relationship between lower SEP and elevated risk of high blood glucose was stronger in the younger birth cohort, and obesity attenuated this inverse relationship in women only.