KATE E. PICKETT,* JERE
D. HAAS,*³ SCOTT MURDOCH,* JUAN A. RIVERA AND REYNALDO
MARTOREAL
*Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, Centro de Investigaciones en Salud Pública, Instituto Nacional de Salud Pública, 62508 Cuernavaca, Morelos, Mexico, and Department of International Health, The Rollins School of Public Health of Emory University, Atlanta, GA 30322
¹ Published as a supplement to The Journal of Nutrition. Guest editors for this supplement publication were Reynaldo Martorell, The Rollins School of Public Health of Emory University, Atlanta, GA and Nevin Scrimshaw, The United Nations University, Boston, MA.
² Supported by NIH grant number RO1-HD22440
³ To whom correspondence should be addressed: Division of Nutritional Sciences, 211 Savage Hall, Cornell University, Ithaca, NY 14853.
ABSTRACT The effect of early childhood nutritional supplementation on skeletal maturation at adolescence was investigated in 663 rural Guatemalans, aged 1118 y. Skeletal maturation was assessed by the Tanner-Whitehouse-2 method. The subjects were former participants in the Institute of Nutrition of Central America and Panama longitudinal study of growth and development (1969-77) residing in four villages (two large and two small) in eastern Guatemala. The villages were randomized within pairs to receive either a high energy, high protein supplement (Atole) or a low energy supplement with no protein (Fresco). Skeletal maturity was observed across all villages to be delayed significantly relative to a British reference for boys<14 y of age, but not for older boys or for girls<14 y of age. Delays in girls>14 years could not be determined reliably because many had reached maturity. Girls<14 years from Atole villages were more advanced in skeletal maturity than similar age girls from Fresco villages but these differences were found only in comparisons of the large villages. The relationship between early nutrition and biological maturation at adolescence may be obscured in this sample by the advanced age at which the subjects were examined in adolescence. J. Nutr. 125:1097S-1103S, 1995. INDEXING KEY WORDS:
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More is known about the effects of early childhood protein-energy malnutrition on growth than on biological maturation. Some studies have shown, however, that early undernutrition delays maturation in both experimental animals (Schroeder and Zeman 1973) and in humans (Alvear et al. 1986, Bailey et al. 1984, Himes 1978). In the Institute of Nutrition of Central America and Panama (INCAP) longitudinal study, maturation was assessed in preschool children by counting the number of ossification centers present in a hand-wrist X-ray (Yarbrough et al. 1973). Effects of nutritional supplementation on maturation were found in both sexes but the differences were of lesser magnitude than those seen on linear growth (Martorell et al. 1979). Approximately 20% of the effects on linear growth could be attributed to accelerated maturation.
The long-term effects of malnutrition in early childhood on growth and development at adolescence are less well known. Associations between stunting in early childhood with patterns of growth in adoleence and with attained adult height have been demonstrated (Billewicz and MacGregor 1982, Hauspie et al. 1980, Satyanarayana et al. 1980, Satyanarayana et al. 1989). Martorell et al. (1990) found that stunting in early childhood in rural Guatemalans persisted into adolescence and that height gain between 5 and 18 y of age was independent of height status at 5 y.
Satyanarayana et al. (1989) found that timing and duration of peak height velocity in an Indian sample was dependent on the degree of stunting at 5 y of age. Cross-sectional studies from developing countries suggest that nutritional status assessed by anthropometry during adolescence is related to maturity indicators such as age at menarche, skeletal age (SA) and the development of secondary sex characteristics (Spurr et al. 1983). However, it is not known whether preschool-age delays in biological maturation related to protein-energy malnutrition persists into adolescence. Biological maturation may be an important mediating factor for the effects of early malnutrition on growth, body composition, work capacity, activity and social development during adolescence - all important outcomes examined in the INCAP follow-up study reported in this volume.
The objective of this research is to assess the long term effects of early childhood nutritional supplementation on biological maturation at adolescence, indicated by SA. The effects of both supplement type (protein-plus-energy vs. Energy) and quantity on maturation at adolescence are investigated in a follow-up sample of the INCAP longitudinal study. Effects on menarche are considered elsewhere (Khan et al. 1995).