Adipokines in Obese Adolescents With Insulin Resistance

The increased prevalence of obesity in pediatric patients is a public health problem particularly because of the difficulties involved with changing lifestyles. Current studies of obese children and adolescents show increased insulin resistance (IR) and chronic inflammatory states. These conditions increase the risk of disability and/or premature death.

The current treatment schemes for obese children are conservative and are focused on changing their lifestyles (exercise and dietary plans). However, metabolic conditions, such as IR, dyslipidemia, and inflammatory processes, are perpetuated.

Metformin is a biguanide that is used for adolescents with diabetes mellitus and polycystic ovarian syndrome. Several clinical trials with metformin for obese pediatric patients have observed decreases in IR, decreases in weight, and improvements in lipid metabolism.

Adipose tissue is not only an energy repository, but also plays an immunological role by the secretion of cytokines. Both overweight adults and adolescents show decreases in adiponectin levels and increases in tumor necrosis factor alpha (TNFα) and interleukin 6 (IL-6). IL-6 can stimulate the production of high-sensitivity C-reactive protein (hs-CRP), which is considered to be a risk marker for the development of cardiovascular disease.

Inclusion criteria

• Obesity defined as Body Mass Index (BMI) ≥ percentile 95
• Tanner stage ≥ 2
• Insulin resistance defined as Basal insulin > 15 µU/mL or Homeostasis Model Assessment index (HOMA) > 4.5
• Patients' parents signed written consents when they and their adolescent children agreed to enroll

Exclusion criteria

• Glucose intolerance
• Diabetes mellitus (type 1 or 2)
• Anemia (Hb < 10 g/dL)
• Plasma creatinine > 1.4 mg/dL
• Abnormal hepatic function
• Any associated Disease (Pulmonary, Infection, Autoimmune Disease)
• History of lactic acidosis