Sexual dimorphism in schoolchildren of the Villa IAPI neighborhood (Quilmes, Buenos Aires, Argentina).

Villa IAPI is a poor neighborhood of about 5,000 inhabitants in the overpopulated conurbano bonaerense at the outskirts of the city of Buenos Aires. Most of the adult male residents are construction workers; the rest are temporary workers, underemployed, or unemployed. The inhabitants of Villa IAPI suffer the effects of many adverse socio-economic conditions, including poor nutrition, deficient sanitation, and inadequate medical care. Seven anthropometric variables were measured on 765 children from 6 to 14 years old to test for the presence of an altered pattern of sexual dimorphism. It was found that there were practically no sex differences in standing height and upper-arm muscle circumference. In some age groups, there was a weak but significant sexual dimorphism in body weight and sitting height. The greatest and most persistent dimorphism was found in head circumference, and in triceps and subscapular skinfolds. In all except two age groups, head circumference in males was significantly greater than in females. The other dimorphic variables (body weight, sitting height, and triceps and subscapular skinfolds) showed the opposite relationship. Essentially, females showed increments in subcutaneous fat, while reduced growth in muscle and bone was evident in males. The hypothesis of "better female canalization" can explain the altered dimorphic pattern found in the malnourished Villa IAPI population.

[Growth in school children of Villa IAPI (Quilmes, Buenos Aires, Argentina)]. / Crecimiento en escolares de Villa IAPI (Quilmes, Buenos Aires, Argentina).

Growth in schoolchildren of Villa IAPI--a poor neighborhood placed near Buenos Aires (Argentina)--were cross-sectionally studied. Six hundred and forty five--291 males and 354 females--children from six to twelve years old were weighed (W), and the standing (StH) and sitting (SiH) heights, the head (HC) and the arm (AC) circumferences, and the triceps (TS) an the subscapular (SS) skinfolds were measured. The muscular braquial circumference (MC), and the length of the inferior segment of the body (IS) were also calculated. All of the measurements were transformed to "z" scores. It was observed that in all cases--except for 11 year-old females--both W and StH were diminished. This trend was stronger in males than in females. Both SiH an HC did not show differences with respect to local growth standards. Skinfold values however, were always greater in Villa IAPI children--except SS in 9 to 12 year-old males, and in 12 year-old females--than those of normal standards, Such differential growth pattern suggests that two joined strategies--for protection and adaption to unbalanced environment--actually acted in the Villa IAPI population.