Urban-rural contrasts in the growth status of school children in Oaxaca, Mexico

Abstract

Objectives: The growth status of school children resident in an urban colonia and in a rural indigenous community in Oaxaca, southern Mexico, was considered in the context of two objectives, current status and the magnitude of urban-rural differences over a span of about 30 years. Both communities were initially surveyed in 1968 and 1972.

Materials and methods: Height, body mass, segment lengths, skeletal breadths, limb circumferences, and subcutaneous fatness were taken on 361 rural (177 boys, 184 girls) and 339 urban (173 boys, 166 girls) school children, aged 6-13 years. Additional variables were derived.

Results: Height and body mass were significantly greater in urban compared with rural children. Sitting height, estimated leg length and skeletal breadths on the trunk were also larger in urban than in rural school children, but only the difference in skeletal breadths was significant after age and body size were statistically controlled. Urban and rural children did not consistently differ in skeletal breadths on the extremities and limb circumferences. Subcutaneous fatness was more variable. After controlling for age and body size, rural girls had thicker skinfolds. The magnitude of the urban-rural difference in boys in 2000 was greater for body mass, BMI and triceps skinfold, and reduced for height, sitting height, leg length, and arm and estimated arm muscle circumferences compared with 1970. The magnitude of the urban-rural difference in girls was greater in 2000 than 30 years earlier for body mass, height, sitting height, leg length and BMI. Urban-rural differences for arm and arm muscle circumferences and the triceps skinfold were slightly smaller over the interval.

Conclusions: Children resident in an urban colonia were taller and heavier than children resident in a rural indigenous community. After controlling for age and body size, urban-rural differences in skeletal breadths and limb circumferences were reduced or eliminated, but skinfold thicknesses were greater in rural girls. The magnitude of urban-rural differences in body size has decreased over approximately 30 years in boys, but has increased in girls.