Abstract 30: Body Mass Index Is Associated With Markers Of Inflammation And Liver Damage Among Healthy Adolescents

Abstract

Objectives: Obesity is the main cause of non-alcoholic fatty liver disease. Clinical studies reported that adolescent obesity is also associated with elevated levels of inflammatory markers and liver enzymes. However, it is unclear whether adolescents’ body mass index (BMI) within the normal range is associated with inflammatory marker or liver enzyme levels. Thus we investigated the association of BMI with C-reactive protein (CRP) and alanine aminotransferase (ALT) levels in healthy Korean adolescents. Methods: The JSHS Study is a prospective cohort study to investigate the risk factors for vascular change in early life. The current cross-sectional analysis enrolled 540 boys and 506 girls, aged 15-16 years old, who participated in the baseline examinations between 2007 and 2012. Baseline measurements included anthropometrics, physical examinations, questionnaires, and fasting blood analysis. Spearman correlation and linear regressions analyses were used to investigate the association of BMI with CRP and ALT. All statistical analyses were performed separately for males and females. Results: CRP levels were positively correlated with BMI in males (correlation coefficient r=0.175, p<0.001) and females (r=0.206, p<0.001). After adjustment for age, smoking and alcohol consumption, higher BMI was positively associated with increased CRP levels (β=0.157, p<0.001 for male; β=0.195, p<0.001 for female). But this association was attenuated (β=0.091, p=0.074 for male; β=0.085, p=0.091 for female), when the analysis was limited to adolescents with normal range of BMI (18.5 to 25.0 kg/m2). ALT levels were positively correlated with BMI only in males (correlation coefficient r=0.337, p<0.001) but not in females (r=0.072, p=0.104). After adjustment for age, smoking and alcohol consumption, higher BMI was positively associated with increased ALT levels (β=0.436, p<0.001 for male; β=0.094, p=0.034 for female). But this association was significant only in males (β=0.190, p<0.001) not in females (β=0.074, p=0.143), when the analysis was limited to adolescents with normal range of BMI. Conclusion: Higher BMI was positively associated with increased levels of CRP and ALT among healthy Korean adolescents. The positive association between BMI and ALT levels was observed even in male adolescents with normal range of BMI.