Childhood Obesity: A Multisystem Challenge Linking Hypertension, NAFLD, and Sleep Apnea

: Childhood overweight and obesity represent a major global public health emergency, with a steadily increasing prevalence over recent decades in both developed and developing countries. Approximately one fifth of children and adolescents are overweight or obese, with marked differences across ethnic groups and geographical areas. Accurate estimation of this condition is complicated by the lack of a unique and universally accepted definition of childhood obesity, which is based on different anthropometric criteria. Although body mass index (BMI) remains the most widely used tool, growing evidence indicates that abdominal obesity, assessed by waist circumference and waist-to-height ratio, is a better predictor of cardiometabolic risk, even in children with a normal BMI. Childhood obesity is associated with several comorbidities, including arterial hypertension, non-alcoholic fatty liver disease (NAFLD) and obstructive sleep apnea syndrome (OSAS). Early diagnosis and an integrated therapeutic approach are essential to reduce the risk of long-term complications. Although lifestyle modifications remain the cornerstone of treatment, new pharmacological options for pediatric obesity have been approved in recent years. This narrative review explores the impact of childhood obesity on the early development of hypertension, NAFLD, and OSAS, emphasizing the implications that can already be observed during childhood and adolescence. It examines the association between pediatric obesity and these conditions by synthesizing current epidemiological evidence, describing the underlying pathophysiological mechanisms linking excess adiposity to disease onset, and reviewing pediatric-specific diagnostic criteria as well as preventive and therapeutic strategies.