This Article Full Text Full Text (PDF) Submit a related Letter to the Editor Purchase Article View Shopping Cart Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Remer, T. Articles by Manz, F. Search for Related Content PubMed PubMed Citation Articles by Remer, T. Articles by Manz, F.

The Midgrowth Spurt in Healthy Children Is Not Caused by Adrenarche

Research Institute of Child Nutrition Dortmund, D-44225 Dortmund, Germany

Address all correspondence and requests for reprints to: Thomas Remer, Ph.D., Research Institute of Child Nutrition, Forschungsinstitut fuer Kinderernaehrung, Heinstueck 11, D-44225 Dortmund, Germany. E-mail: remer{at}fke-do.de

Abstract

A small transient increase in growth, the midgrowth spurt, has been observed in several growth studies in healthy children around the age of 7 yr. During this time adrenarche (the physiological increase in adrenal androgen secretion) also occurs. Although it is now well established that estrogen, not androgen, has a critical role in the male (and female) pubertal growth spurt, a direct effect of androgens on growth cannot be excluded. In accordance with published observations that growth is frequently accelerated in infants and young children with late-diagnosed 21-hydroxylase deficiency (before adequate androgen suppression), it has been speculated that the adrenarchal increase in adrenal androgen secretion in healthy children could be responsible for the midgrowth spurt. To test this hypothesis we studied long-term serial changes in urinary 24-h excretion rates of dehydroepiandrosterone sulfate and total 17-ketosteroid sulfates in a group of healthy children (n = 12) in which yearly auxological measurements allowed the identification of a midgrowth spurt. Annual measurements of standing height were performed over periods of 6–9 yr before the onset of puberty. All children collected five to seven serial 24-h urine samples (1-yr intervals) each at the time of anthropometric examination. The peak of the midgrowth spurt was found to occur at a mean age of 6.8 ± 1.0 yr. The average height of the midgrowth peak, i.e. average maximum gain in height velocity, was 0.9 cm/yr. In a peak-centered examination of individual 24-h excretion rates of dehydroepiandrosterone sulfate and 17-ketosteroid sulfates, primarily weak 1-yr changes in adrenal androgens were observed until the peak was attained. Only after the peak did increments in urinary adrenal androgen output become more pronounced.

ANOVA performed on the peak-centered dehydroepiandrosterone sulfate and 17-ketosteroid sulfate excretion rates revealed a highly significant overall increase in adrenal androgen secretion from 2 yr before to 2 yr after the midgrowth spurt. After multiple testing, however, significant increments, when compared with the respective preceding androgen excretion levels, were for the first time seen 1 yr after the midgrowth spurt (dehydroepiandrosterone sulfate) or 2 yr later (17-ketosteroid sulfates). In conclusion, our longitudinal analysis of prepubertal growth and urinary adrenal androgen excretion in healthy children disproves the speculation that the midgrowth spurt is primarily caused by the adrenarchal increase in adrenal androgen secretion. However, the present results do not rule out a growth-accelerating effect of clearly higher androgen levels, as in premature adrenarche.

This article has been cited by other articles:

				Z Hochberg Juvenility in the context of life history theory Arch. Dis. Child., June 1, 2008; 93(6): 534 - 539. [Abstract] [Full Text] [PDF]

				J. L. CAMERON Interrelationships between Hormones, Behavior, and Affect during Adolescence: Understanding Hormonal, Physical, and Brain Changes Occurring in Association with Pubertal Activation of the Reproductive Axis. Introduction to Part III Ann. N.Y. Acad. Sci., June 1, 2004; 1021(1): 110 - 123. [Abstract] [Full Text] [PDF]

				T. Dimitriou, C. Maser-Gluth, and T. Remer Adrenocortical activity in healthy children is associated with fat mass Am. J. Clinical Nutrition, March 1, 2003; 77(3): 731 - 736. [Abstract] [Full Text] [PDF]