Clinical aspects of obesity in childhood and adolescence - diagnosis, treatment and prevention

level of fatness at which morbidity increases is determined on an acturial basis. Direct measurements of body fat content, eg hydrodensitometry, bioim pedance or DEXA, are useful tools in scientific studies. However, body mass index (BMI) is easy to calculate and is frequently used to define obesity clinically. An increased risk of death from cardiovascular disease in adults has been f ound in subjects whose BMI had been greater than the 75th percentile as ado lescents. Childhood obesity seems to increase the risk of subsequent morbid ity whether or not obesity persists into adulthood. The genetic basis of childhood obesity has been elucidated to some extent t hrough the discovery of leptin, the ob gene product, and the increasing kno wledge on the role of neuropeptides such as POMC, neuropeptide Y (NPY) and the melanocyte concentrating hormone receptors (MC4R). Environmental/exogen ous factors contribute to the development of a high degree of body fatness early in life. Twin studies suggest that approximately 50% of the tendency toward obesity is inherited. There are numerous disorders including a numbe r of endocrine disorders (Cushing's syndrome, hypothyroidism, etc) and gene tic syndromes (Prader- Labhard-Willi syndrome, Bardet-Biedl syndrome etc) t hat can present with obesity. A simple diagnostic algorithm allows for the differentiation between primar y or secondary obesity. Among the most common sequelae of primary childhood obesity are hypertension, dyslipidemia and psychosocial problems. Therapeutic strategies include psychological and family therapy, lifestyle/ behavior modification and nutrition education. The role of regular exercise and exercise programs is emphasized. Surgical procedures and drugs used as treatments for adult obesity are still not recommended for children and ad olscents with obesity. As obesity is the most common chronic disorder in th e industrialized societies, its impact on individual lives as well as on he alth economics has to be recognized more widely. This review is aimed towards defining the clinical problem of childhood obe sity on the basis of current knowledge and towards outlining future researc h areas in the field of energy homoeostasis and food intake control.