Insulin secretion, insulin sensitivity and diabetes in black children.

Historically, type 2 diabetes has been considered rare in the pediatric population. However, over the last decade, there has been a disturbing upswing in the rate of non-type 1 diabetes in the pediatric age group, particularly adolescents, with a greater proportion of Black children being affected. In this review, the following questions will be addressed: (1) what are the clinical characteristics of youth-onset atypical diabetes, (2) how common is it, (3) what are the risk factors, and (4) how should it be treated?

Growth hormone treatment in adolescent males with idiopathic short stature: changes in body composition, protein, fat, and glucose metabolism.

Context: Cross-sectional observations show an inverse relationship between pubertal increase in GH and insulin sensitivity, suggesting that pubertal insulin resistance may be mediated by GH.

Objective: Our objective was to assess longitudinally the effects of short-term GH supplementation in adolescent males with non-GH-deficient idiopathic short stature (ISS) on body composition, substrate metabolism, and insulin sensitivity. Children with ISS were studied to simulate the pubertal increase in GH secretion.

Short-term pharmacologically induced growth study of ontogenetic allometry of oxygen uptake in children.

Background: A range of allometric coefficients have been proposed in describing the maximal oxygen uptake (VO2max): body mass relation in children using weight-bearing ergometry. However, a wide deviation in the allometric coefficients for VO2max may be apparent when selected pediatric cohorts are studied in conjunction with clinical intervention for growth abnormalities.

Aim: The purpose of this study was to determine the allometric coefficients for VO2max after short-term pharmacologically induced growth in pre- and early pubescent children.

Insulin resistance of puberty in African-American children: lack of a compensatory increase in insulin secretion.

Type 2 diabetes has been increasing in children, mostly affecting minority populations at around the age of puberty. Despite a multitude of studies demonstrating pubertal insulin resistance/hyperinsulinemia in white children, data are almost non-existent in African-American children. The aim of the present study was to investigate the impact of puberty on glucose metabolism, insulin sensitivity and secretion in African-American children.

Hyperinsulinemia in african-american children: decreased insulin clearance and increased insulin secretion and its relationship to insulin sensitivity.

African-American (AA) children are hyperinsulinemic and insulin resistant compared with American White (AW) children. This study investigated 1) whether AA/AW differences in insulinemia are associated with differences in insulin clearance; 2) whether dietary patterns, mainly carbohydrate and fat intake, play a role; and 3) whether the quantitative relationship between insulin sensitivity and secretion is similar between AA and AW children. Forty-four prepubertal children (22 AA and 22 AW) with comparable body composition and visceral adiposity were studied.

Metformin therapy in obese adolescents with polycystic ovary syndrome and impaired glucose tolerance: amelioration of exaggerated adrenal response to adrenocorticotropin with reduction of insulinemia/insulin resistance.

Functional adrenal hyperandrogenism occurs in women with polycystic ovary syndrome (PCOS). Insulin, similar to its ovarian effect, may impact the regulation of adrenal steroidogenesis by modulating the activity of P450c17alpha, the rate-limiting enzyme in androgen biosynthesis. We previously demonstrated that obese adolescents with PCOS are severely insulin resistant and are at heightened risk for impaired glucose tolerance and type 2 diabetes.

Dihydrotestosterone treatment in adolescents with delayed puberty: does it explain insulin resistance of puberty?

Puberty is characterized by temporary insulin resistance, which subsides with the completion of pubertal development. This insulin resistance is manifested by lower rates of insulin-stimulated glucose metabolism and compensatory hyperinsulinemia in pubertal compared with prepubertal children. Whether or not pubertal insulin resistance is the result of sex steroids or GH or a combination of both has been investigated in our laboratory.

Lipolysis in African-American children: is it a metabolic risk factor predisposing to obesity?

Rates of obesity and type 2 diabetes are higher in African-American (AA), compared with American white (AW), adults and children. It is not known whether biologic and/or environmental differences are responsible for this racial disparity. We and others have demonstrated that AA children are hyperinsulinemic, compared with their AW peers.

Glucose intolerance in obese adolescents with polycystic ovary syndrome: roles of insulin resistance and beta-cell dysfunction and risk of cardiovascular disease.

The roles of insulin resistance and insulin secretion in the pathogenesis of glucose intolerance in polycystic ovary syndrome (PCOS) were evaluated in 11 adolescents with impaired glucose tolerance (IGT) and 10 with normal glucose tolerance (NGT). Hepatic glucose production and insulin-stimulated glucose disposal were measured using [6,6-(2)H(2)]glucose and a 3-h hyperinsulinemic (80 mu/m(2).min)-euglycemic clamp.

Early metabolic abnormalities in adolescent girls with polycystic ovarian syndrome.

Objective: To investigate insulin sensitivity and secretion in young adolescent girls with childhood onset polycystic ovarian syndrome (PCOS) and to identify the early metabolic derangement(s).

Study Design: Twelve obese girls with PCOS (age 12.0+/-0.

Determination of body composition in African-American children: validation of bioelectrical impedence with dual energy X-ray absorptiometry.

Body compositional differences between Black and White adults are well-known. It has become increasingly apparent that these racial variations may begin in childhood. Previously, our group validated tetrapolar bioelectrical impedance (BIA) measurements against H2(18O) dilution method to develop prediction formulas of fat free mass (FFM) in healthy White-American children: FFM = 0.

Leptin in African-American children.

Leptin, the protein product of the obesity gene, produced by adipose tissue, regulates body weight and energy expenditure through CNS feedback mechanisms. In obesity, leptin levels are elevated suggestive of leptin resistance. Because of increased prevalence of obesity in African-Americans, the aim of this study was to assess leptin and its relationship to adiposity in African-American children.

Insulin sensitivity in African-American children with and without family history of type 2 diabetes.

Objective: African-Americans are at increased risk for type 2 diabetes. We have previously demonstrated that African-American children are hyperinsulinemic and insulin resistant compared with their white American peers. The aim of the present investigation was to assess the impact of family history of type 2 diabetes on insulin sensitivity in African-American children.

Outcome and cost of child abuse.

Objective: To compare the cases of child abuse (CA) with other admissions in a pediatric intensive care unit (PICU) for differences in patient-specific health care costs, severity of illness (SI) and mortality, and describe their outcome.

Method: A retrospective cohort study of all patients admitted to the PICU between January 1991 and August 1994. Discharge diagnosis, age, SI, mortality rate, length of stay, hospitalization charges ($Hosp), and mortality were retrieved.