The prevalence of childhood obesity in children has reached alarming levels, and it’s estimated that about 1 billion people worldwide are overweight, with 22 million being under the age of 5 years.

The reasons for childhood obesity include environmental factors, lifestyle preferences, and also cultural background. An increase in caloric and fat intake is one of the major causes for developing overweight and obesity and there is rising evidence that a marked decline in physical activity also plays a major role in the dramatically increasing rates of childhood obesity worldwide.

This study compared 80 obese or overweight children at an average age of 12 years with 60 age-matched lean control children. The researchers took blood samples to determine cholesterol levels and performed a so called "oral glucose tolerance testing", a test investigating the individual blood glucose response to a defined amount of glucose intake. With this standardized test they are able to detect diabetes or pre-diabetic alterations like insulin resistance.

As measures of vessel injury we determined intima-media-thickness of the carotid artery and endothelium-dependent relaxation of the forearm, both well-established markers of early vessel alteration which are easily and non-invasively assessable.

Since its known that vessel integrity is strongly associated with self-healing processes managed by the body's own bone-marrow-derived stem or precursor cells, the researchers measured the number and function of specific stem cells in the blood that are known to contribute to vessel repair und formation of new blood vessels.

The researchers were able to show that at an average of 12 years obese or overweight children suffer from pre-diabetes as indicated by much higher levels of insulin in oral glucose tolerance testing compared to lean healthy children. The concentration of "bad" LDL cholesterol was higher in obese children and "good" HDL cholesterol much less in obese children. In obese children 24 h-blood pressure monitoring indicates an about 8 to 10 mmHg higher systolic blood pressure over the day. Nearly all components of metabolic syndrome are evident in populations of obese children.

Endothelium-dependent relaxation of forearm arteries is already impaired equivalent to adults with chronic heart failure, and this in 12-years old obese children. A clear relationship was found between the degree of obesity and the impairment of endothelial function: those with the highest body weight had the worst vessel function.

Also the extent of intima-media-thickness of carotid artery was increased, and this was again more pronounced in those with severe obesity.

These vascular alterations are accompanied by a significantly impaired release of stem and precursor cells from the bone marrow indicating that self-healing capacity might be diminished.

Considering these disastrous alterations of arterial vessels and also the hampered repair mechanisms in obese children, it is not surprising that this vascular drama obligatory results in atherosclerosis followed by acute myocardial infarctions or strokes even in young adults.

Therefore, primary or secondary prevention strategies starting early in childhood should aim at reversing current increase in childhood obesity. A number of potential strategies can be implemented to target built environment, physical activity, and diet. These strategies can be initiated at home and in preschool institutions, schools or after-school care services as natural setting to influence diet and physical activity in the entire children population. However, further research needs to explore the most effective strategies to prevent and treat childhood obesity.
References:
1. Sandra Erbs. European Society of Cardiology Congress 2009.