Pediatric metabolic syndrome: pathophysiology and molecular mechanisms

The current obesity epidemic, a condition of excess body fat that may damage health [1], is becoming an increasingly a major health risk worldwide. Over the past few decades, the emergence of this phenomenon in pediatric populations has become a significant challenge for health practitioners. Especially when it is localized within the abdominal region (central obesity), obesity is associated with an increase in metabolic and cardiovascular risk factors and can eventually lead to the development of type 2 diabetes. Obesity is now regarded as one common pathological component of the metabolic syndrome, also called syndrome X or insulin-resistance syndrome. In adults, the International Diabetes Federation [2,3,4] defines the metabolic syndrome as a cluster of risk factors for cardiovascular disease, including visceral adiposity, hypertension, hyperglycemia and dyslipidemia [5]. This definition has been redefined in the pediatric population due to various changes in body size, fat distribution and proportions with age and development. Therefore, children and adolescents are separated into three age groups: age 6 to 9 years, age 10 to 15 years, and age 16 years and older [3]. There are insufficient data available for children below 6 years of age. The aim of the present review is to present the main features of the pediatric metabolic syndrome and to provide some insight into the underlying pathophysiological mechanisms.