Relationships between 25-hydroxyvitamin D levels and plasma glucose and lipid levels in pediatric outpatients.

OBJECTIVE: To study the relationships between serum vitamin D levels and plasma glucose or lipid levels in children and adolescents. STUDY DESIGN: We conducted a retrospective record review of pediatric outpatients (age, 2-18 years) with simultaneous measurement of 25-hydroxyvitamin D (25[OH] D) and fasting plasma glucose (n = 302) or 25(OH) D and a lipid panel (n = 177). Pearson correlation coefficient was used to estimate the correlation between 25(OH) D and logarithmic transformed plasma glucose or lipid levels. Plasma glucose and lipid levels were compared in subjects with 25(OH) D concentrations greater or less than 30 ng/mL. RESULTS: 25(OH) D levels were inversely correlated with fasting plasma glucose levels (r = -0.20, P < .001). Lower 25(OH) D levels were also associated with lower serum high-density lipoprotein cholesterol (HDL) concentrations (r = 0.41; P < or = .001). The relationship between 25(OH) D levels and fasting glucose and HDL levels did not vary significantly with sex, age, body mass index z-score, or season. Children who were vitamin D insufficient (25[OH] D < or =30 ng/mL) had higher fasting plasma glucose (P = .002) and lower HDL levels (P < .001) than children who were vitamin D sufficient (25[OH] D >30 ng/mL). CONCLUSIONS: Low 25(OH) D levels in children and adolescents are associated with higher plasma glucose and lower HDL concentrations.

Cystic changes in the ovaries of a pre-pubertal girl with Henoch-Schönlein purpura.

Henoch Schönlein Purpura is an IgA mediated vasculitis that is known to be associated with scrotal pathology. However, an association between Henoch Schönlein purpura and ovarian pathology has not been described. We present the case of a girl who developed cystic changes in her ovaries during her course of Henoch Schönlein purpura.

Type 2 diabetes mellitus in children and adolescents: where do we stand with drug treatment and behavioral management?

Type 2 diabetes, once considered a disease of adults, is a growing problem in the pediatric population. The emergence of type 2 diabetes in this age group has paralleled the epidemic of childhood obesity. Lifestyle modifications represent first-line therapy for children and adolescents with type 2 diabetes. However, many children and adolescents go on to require treatment with oral medications or insulin for optimal control. A paucity of data exist regarding the optimal treatment regimen for children and adolescents with type 2 diabetes. Further research regarding the treatment of type 2 diabetes in youth is required.

Effect of vitamin D3 supplementation on serum 25(OH)D, lipids and markers of insulin resistance in obese adolescents: a prospective, randomized, placebo-controlled pilot trial.

BACKGROUND/AIMS: To determine the effect of vitamin D3 supplementation on 25-hydroxyvitamin D [25(OH)D], lipid profile and markers of insulin resistance in obese adolescents. METHODS: In this double-blind, randomized, placebo-controlled trial, 58 obese adolescents (n = 58; 12-18 years of age) received either vitamin D3 (2,000 IU/day) or placebo for 12 weeks. Total 25(OH)D, fasting plasma glucose, insulin and lipid profile were measured at baseline and following supplementation. RESULTS: The trial was completed by 44/58 enrolled participants. At the end of the 12 weeks, total serum 25(OH)D concentrations increased to a modest degree (median 6 ng/ml) in the vitamin D-supplemented group (p < 0.001). Supplementation showed no detectable changes in fasting plasma glucose, insulin, homeostatic model of assessment index (HOMA-IR), lipids and highly sensitive C-reactive protein. CONCLUSIONS: 12 weeks of vitamin D3 supplementation in obese adolescents with 2,000 IU once daily resulted in a modest increase in 25(OH)D concentration in obese adolescents, but did not affect the lipid profile and markers of insulin resistance and inflammation. Further studies with higher doses of vitamin D3 and/or longer duration of supplementation are needed to understand if vitamin D3 supplementation can impact lipid profiles and markers of insulin resistance and inflammation in obese children.

Relationships between thyroid function and lipid status or insulin resistance in a pediatric population.

BACKGROUND: In adults without thyroid disease, increasing levels of thyroid-stimulating hormone (TSH) within the range of that considered normal have been shown to be associated with increases in total cholesterol, low-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol, and triglycerides, and with decreases in high-density lipoprotein cholesterol. Serum TSH has also been found to be positively associated with fasting and postload insulin concentrations and negatively associated with insulin sensitivity in euthyroid adults. We hypothesized that such relationships also exist in euthyroid children and adolescents. METHODS: This was a retrospective record review of pediatric outpatients (ages 2-18 years) having measurements of TSH or free thyroxine (T4) and a concurrent lipid panel, fasting glucose, or fasting insulin. Pearson correlation coefficient was used to estimate the correlation between TSH or free T4 and logarithmic transformed lipid, plasma glucose, or insulin levels. Lipid levels, fasting plasma glucose, insulin, and homeostasis model assessment (HOMA) were also compared between subjects with TSH levels in the high normal range (2.5-5 mIU/L) and those with TSH in the low normal range (0.3-2.4 mIU/L). RESULTS: TSH levels were positively correlated with triglyceride levels (r = 0.10, p = 0.001). Conversely, free T4 levels were inversely correlated with triglyceride levels (r = -0.10, p = 0.011). TSH levels were also positively correlated with fasting insulin (r = 0.26, p = 0.002) and with HOMA (r = 0.27, p = 0.001). These associations remained significant after adjustment for age, gender, and body mass index z-score. Children who had TSH levels between 2.5 and 5.0 mIU/L had higher triglycerides (p = 0.003), insulin levels (p = 0.040), and HOMA (p = 0.021) than those having TSH values between 0.3 and 2.4 mIU/L. CONCLUSIONS: In euthyroid children without a history of hypo- or hyperthyroidism, increasing levels of TSH and decreasing levels of free T4 are associated with higher triglyceride levels and elevated markers of insulin resistance. Whether these findings carry implications regarding optimal TSH levels in children at increased risk for cardiovascular disease awaits further study.