Clinical, Anthropometric and Metabolic Profile of Non-Alcoholic Fatty Liver Disease in Obese Adolescents: A Hospital-Based Cross-Sectional Observational Study

Abstract

Background: Non-alcoholic fatty liver disease, now designated metabolic dysfunctionassociated steatotic liver disease, is the commonest chronic liver disorder of childhood and tracks closely with the rising prevalence of adolescent obesity in India. Because the condition is largely asymptomatic and hepatic transaminases are frequently normal, the clinical and metabolic phenotype that identifies affected adolescents remains incompletely characterised in Indian hospital populations. This study was undertaken to determine the prevalence of the disorder among obese adolescents and to define its clinical, anthropometric, biochemical and sonographic profile. Methods: A hospital-based crosssectional observational study was conducted over six months in the Department of Paediatrics of a tertiary care teaching hospital. One hundred and twenty adolescents aged 10 to 19 years with a body mass index at or above the 95th centile for age and sex on the revised Indian Academy of Paediatrics growth charts were enrolled by consecutive sampling. Participants with significant alcohol intake, viral or autoimmune hepatitis, Wilson disease, hepatotoxic drug exposure or secondary obesity were excluded. All underwent anthropometry, blood pressure measurement, fasting biochemistry including transaminases, lipids, glucose and insulin, and abdominal ultrasonography graded by a single blinded radiologist. Results: Fatty liver was detected in 76 of 120 participants, a prevalence of 63.3% (95% confidence interval 54.6 to 72.0). Affected adolescents had a higher body mass index z-score (2.48±0.44 versus 2.10±0.46; p<0.001), waist-to-height ratio (0.63±0.05 versus 0.58±0.05; p<0.001), alanine aminotransferase (48.6±22.4 versus 26.2±10.8 U/L; p<0.001) and HOMA-IR (5.28±2.46 versus 3.06±1.42; p<0.001), and lower high-density lipoprotein cholesterol (p<0.001). Grade 1, 2 and 3 steatosis occurred in 53.9%, 35.5% and 10.5% respectively, and transaminases, HOMA-IR and triglycerides rose progressively across grades. On multivariable analysis, HOMA-IR, body mass index z-score, waist-to-height ratio, acanthosis nigricans and triglycerides were independently associated with the disorder. Conclusion: Nearly two-thirds of obese adolescents attending a tertiary centre had sonographic fatty liver, and insulin resistance and central adiposity rather than absolute weight identified those affected. Routine anthropometric and metabolic screening of obese adolescents is warranted.