RAMB - Julho 2016

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2016; 62(6):479-481

Therefore, in the late 20

century we witnessed great-

er control of infectious and contagious diseases in child-

hood, in parallel with improved socioeconomic and cul-

tural conditions in the country. This, coupled with the

advancement of scientific knowledge and greater techno-

logical resources, caused a significant reduction in infant

mortality and a change in the epidemiological profile.

The therapeutic and pharmacological possibilities in the

field of medicine were expanded. Pediatrics expanded its

limits and pediatric specialties gained an important di-

mension in daily practice, given that the deepening of

knowledge demands professionals that are prepared to

explore all the diagnostic and therapeutic possibilities

for chronic diseases, which went on to take an important

role in pediatric epidemiology.

Simultaneously, preventive pediatrics expanded with

the advancement of the knowledge provided by neuro-

science about child development and new ways of under-

standing the origins of health and disease, all based on

the growth process in human beings.

On the one hand, it is now known that the overall

conditions during pregnancy and the first 2 years of life

are determinants of brain structure. The stimuli trans-

mitted to the brain by the sensory circuits in these peri-

ods differentiate and stimulate the function of neurons

and brain circuits that will form the basis of children’s

capacity for future development and cognition. The my-

elination process and the formation of synapses compos-

ing a complex neuronal network will enable the child to

acquire the neurological and psychomotor skills that will

form their essential personal assets for acquiring the skills

inherent in life, such as talking, reasoning, having the

ability to learn and perform and to develop under the

psycho-emotional aspect.

8,9

Studies conducted in orphan-

ages in Romania have shown abnormal brain develop-

ment, proven by electroencephalogram (EEG) and low

metabolic activity, related to negative experiences and

lack of emotional bonds.

More and more is being un-

derstood about the brain damage that persistent stress-

ful experiences during the first year of life can induce.

Toxic stress, through high cortisol levels, is related to low-

er connectivity between the amygdala (responsible for

processing fear and emotions) and the prefrontal cortex.

Stress in the early years of life is a risk factor for various

psychological and physical problems, mood disorders

and substance abuse, obesity, and cardiovascular diseas-

es. Many studies have demonstrated that, for certain in-

dividuals, childhood experiences permanently alter the

way the body and brain deal with stress.

On the other hand, it is currently understood that

chronic diseases in adults, essentially those that make up

metabolic syndrome such as obesity, diabetes, and car-

diovascular disease, may have their origins in intrauter-

ine life and early life.

12-15

According to the thrifty pheno-

type hypothesis, proposed by Barker, when exposed to

restriction of essential nutrients, a fetus may develop with

a restricted body, adapted to an external life of scarcity.

This can be an advantage, provided that the external en-

vironment remains poor in nutrients. However, if the ex-

ternal environment is plentiful and has no nutritional re-

strictions, this thrifty phenotype can be a disadvantage,

making it unbalanced and more exposed to the chronic

diseases of adulthood.

Furthermore, the number of

nephrons may be reduced due to intrauterine restrictions,

as well as the morphological and functional changes re-

sulting from exposure of the fetus and child to high lev-

els of glucocorticoids in the first months of life.

Cur-

rent studies go further, blaming intrauterine damage and

harm during childhood for adult illnesses, especially car-

diovascular, endocrine, and lung diseases.

Furthermore, it is known that not only the quantity

but also the quality of the mother’s and child’s nutrition

in the early years may interfere in the path to health or

risk of disease. Lipids are essential for the fetus’ and child’s

growth and development. Cell membranes composed of

a lipid bilayer essentially rich in long-chain polyunsatu-

rated essential fatty acids made up of docosahexaenoic

acid (DHA) and arachidonic acid (ARA) determine the

degree of fluidity of fetal cell membranes. Greater fluid-

ity of the membrane ensures the most efficient cellular

homeostasis, which is an essentially important factor for

the development of the central nervous system. Thus,

DHA and ARA are essential for cellular homeostasis, for

the development of the central nervous system (CNS), the

metabolism, and the immune system, among others.

18,19

In the social field, the family and social structure also

changed at the beginning of this century. Families tradi-

tionally composed of father, mother, and children have

given way to new ties of parental affection and new nu-

clear compositions. Children grow and develop in vari-

ous environments and have to learn to adapt to different

ways of living very early. Day care centers, nurseries and

schools become part of children’s daily lives as soon as

the mother’s maternity leave ends. Emotional bonds are

also formed with caregivers, expanding the emotional

universe of childhood. However, if children are gaining

more space in the emotional context, with greater and

earlier socialization on the one hand, they are losing phys-