Sex non-specific growth charts and potential clinical implications in the care of transgender youth.

Introduction: The Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) created separate growth charts for girls and boys because growth patterns and rates differ between sexes. However, scenarios exist in which this dichotomizing "girls versus boys" approach may not be ideal, including the care of non-binary youth or transgender youth undergoing transitions consistent with their gender identity. There is therefore a need for growth charts that age smooth differences in pubertal timing between sexes to determine how youth are growing as "children" versus "girls or boys" (e.g., age- and sex-neutral, compared to age- and sex-specific, growth charts). Methods: Employing similar statistical techniques and datasets used to create the CDC 2000 growth charts, we developed age-adjusted, sex non-specific growth charts for height, weight, and body mass index (BMI), and z-score calculators for these parameters. Specifically, these were created using anthropometric data from five US cross-sectional studies including National Health Examination Surveys II-III and National Health and Nutrition Examination Surveys I-III. To illustrate contemporary clinical practice, we overlaid our charts on CDC 2000 girls and boys growth charts. Results: 39,119 youth 2-20 years old (49.5% female; 66.7% non-Hispanic White; 21.7% non-Hispanic Black) were included in the development of our growth charts, reference ranges, and z-score calculators. Respective curves were largely superimposable through around 10 years of age after which, coinciding with pubertal onset timing, differences became more apparent. Discussion: We conclude that age-adjusted, sex non-specific growth charts may be used in clinical situations such as transgender youth in which standard "girls versus boys" growth charts are not ideal. Until longitudinal auxological data are available in these populations, our growth charts may help to assess a transgender youth's growth trajectory and weight classification, and expectations surrounding these.

Emotional Deprivation in Children: Growth Faltering and Reversible Hypopituitarism.

Emotional deprivation can lead to growth faltering of infants and children. The mechanism(s) involved differ in that for infants, the major metabolic problem is inadequate energy intake for growth. In young children, it is likely that the emotional deprivation causes a syndrome not only of growth faltering, but with bizarre behaviors, especially with regard to food: hoarding, gorging and vomiting, hyperphagia, drinking from the toilet, and eating from garbage pails. Other disturbed behaviors include, poor sleep, night wanderings, and pain agnosia. The pathophysiology appears to be reversible hypopituitarism, at least for the growth hormone and hypothalamic-pituitary- adrenal axes. The review begins with an historical perspective concerning stress, children and growth and then moves to the issue of hospitalism, where young infants failed to thrive (and died) due to inadequate stimulation and energy intake. Refeeding programs at the end of World Wars I and II noted that some children did not thrive despite an adequate energy intake. It appeared that in addition taking care of their emotional needs permitted super-physiologic (catch-up) growth. Next came the first notions from clinical investigation that hypopituitarism might be the mechanism of growth faltering. Studies that address this mechanism from a number of observational and clinical research studies are reviewed in depth to show that the hypopituitarism was relieved upon removal from the deprivational environment and occurred much too quickly to be due to adequate energy alone. These findings are then compared to those from malnourished children and adoptees from emerging countries, especially those from orphanages where their psychosocial needs were unmet despite adequate caloric intake. Together, these various conditions define one aspect of the field of psychoneuroendocrinology.