Metformin for Obesity in Prepubertal and Pubertal Children: A Randomized Controlled Trial

OBJECTIVES

Metformin has shown its effectiveness in treating obesity in adults. However, little research has been conducted in children, with a lack of attention on pubertal status. The objectives were to determine whether oral metformin treatment reduces BMI z score, cardiovascular risk, and inflammation biomarkers in children who are obese depending on pubertal stage and sex.

METHODS

This was a randomized, prospective, double-blind, placebo-controlled, multicenter trial, stratified according to pubertal stage and sex, conducted at 4 Spanish clinical hospitals. Eighty prepubertal and 80 pubertal nondiabetic children who were obese aged 7 to 14 years with a BMI >95th percentiles were recruited. The intervention included 1 g/d of metformin versus placebo for 6 months. The primary outcome was a reduction in BMI z score. Secondary outcomes comprised insulin resistance, cardiovascular risk, and inflammation biomarkers.

RESULTS

A total of 140 children completed the study (72 boys). Metformin decreased the BMI z score versus placebo in the prepubertal group (-0.8 and -0.6, respectively; difference, 0.2; P = .04). Significant increments were observed in prepubertal children treated with metformin versus placebo recipients in the quantitative insulin sensitivity check index (0.010 and -0.007; difference, 0.017; P = .01) and the adiponectin-leptin ratio (0.96 and 0.15; difference, 0.81; P = .01) and declines in interferon-γ (-5.6 and 0; difference, 5.6; P = .02) and total plasminogen activator inhibitor-1 (-1.7 and 2.4; difference, 4.1; P = .04). No serious adverse effects were reported.

CONCLUSIONS

“Metformin decreased the BMI z score and improved inflammatory and cardiovascular-related obesity parameters only in prepubertal children, but a differential effect of metformin was not observed in prepubertal compared to pubertal children. Nevertheless, the doses per kilogram of weight administrated may have had an impact on the metformin effect. Further investigations are necessary.”

Evaluation of differential effects of metformin treatment in obese children according to pubertal stage and genetic variations: study protocol for a randomized controlled trial

Background

Overweight and obesity are considered to be serious public health problems. In pediatric populations, insulin resistance, dyslipidemia, and hypertension associated with obesity occur with increased frequencies. Metformin is an oral anti-hyperglycemic agent that has been demonstrated to be efficacious in the treatment of diabetic and non-diabetic obese adults. A considerable amount of pharmacogenetic research has demonstrated that genetic variation is one of the major factors affecting metformin response. Additionally, potential microbiota-mediated mechanisms of metformin effect have been recently described. However, scant work has been conducted in children, with no attention being paid to the potential effects of pubertal development. Thus, the main objective of the present study is to evaluate the effect of metformin treatment together with lifestyle recommendations in a randomized control trial (RCT) of obese children according to pubertal stage, genetic variants and signature of gut microbiota.

Methods/design

This is a randomized, prospective, double-blind, placebo-controlled, multicenter trial, which is stratified by puberty and sex. Eighty pre-pubertal (40 boys and 40 girls) and 80 pubertal non-diabetic obese children (40 boys and 40 girls) are being recruited in four Spanish Clinical Hospitals. The inclusion criteria to participate in the RCT include a Body Mass Index (BMI) above the 95th percentile and age 7–14 years. The pubertal stage is determined based on the Tanner criteria. Participants are assigned to two groups in accordance with a randomization schedule and receive 1 g of metformin or placebo for six months in combination with healthy lifestyle recommendations in both groups. The primary outcomes include changes in the BMI Z score and the biomarkers associated with the early appearance of insulin resistance syndrome, inflammation, cardiovascular risk according of the presence of genetic determinants of metformin response, as well as possible modifications in microbiota.

Discussion

This study will assess the differential response of metformin treatment at six months in pre-pubertal and pubertal obese children.

Trial registration

Registered by European Clinical Trials Database (EudraCT, ID: 2010-023061-21) on 14 November 2011.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1403-4) contains supplementary material, which is available to authorized users.

Parathyroid hormone response to two levels of vitamin D deficiency is associated with high risk of medical problems during hospitalization in patients with hip fracture

BACKGROUND

Vitamin D and the parathyroid hormone (PTH) response play an important role in hip fracture patients. This study was carried out to determine the factors associated with the PTH response to different levels of vitamin D deficiency during hospitalization.

METHODS

This was a cross-sectional study of patients over 64 years of age admitted with an acute fragility hip fracture between March 1st 2009 and November 30th 2012. Demographic, clinical, functional, and cognitive function were evaluated at admission and during hospitalization. Levels of 25-hydroxyvitamin D (25-OHD) and PTH were analyzed. Two 25-OHD cut-off points were considered, <12 ng/ml and 12-20 ng/ml. Multivariate logistic regression analysis was used.

RESULTS

Mean age of the 607 patients included was 84.7 years (SD 7.10), and 81.9 % were women. The mean 25-OHD level in the total sample was 13.2 (SD 11.1) ng/ml. Levels of 25-OHD <12 ng/ml were present in 347 patients (57.2 %), of whom 158 (45.5 %) had secondary hyperparathyroidism (SHPT) (PTH >65 pg/ml). 25-OHD levels of 12-20 ng/ml were present in 168 (27.7 %) patients, of whom 47 (28 %) had SHPT. Following logistic regression, SHPT was associated in both groups (25-OHD <12 and 12-20 ng/ml) with a greater number of medical problems during hospitalization. In the 25-OHD group <12 ng/ml, SHPT was also associated with poorer glomerular filtration rates.

CONCLUSION

The PTH response to vitamin D deficiency in hip fracture patients may be a marker for patients with higher risk of developing multiple medical problems, both when considering severe (<12 ng/ml) and moderate (12-20 ng/ml) vitamin D deficiency.

Social capital and self-rated health in urban low income neighbourhoods in Chile

OBJECTIVE

To examine the potential association between social capital and self-rated health within a low income community of Santiago, Chile.

METHOD

Cross-sectional survey, based on in-home interviews in the municipality of Puente Alto in Santiago, Chile. The participants were 781 residents of four neighbourhoods within Puente Alto (mean age 45.5 years).

RESULTS

Principal components analysis with varimax rotation identified five domains of social capital: perceived trust in neighbours, perceived trust in organisations, reciprocity within the neighbourhood, neighbourhood integration, and social participation (Cronbach alphas: 0.58 to 0.77). Trust and reciprocity were significantly associated with better self-rated health. For example, a one standard deviation increase in trust in neighbours was associated with an adjusted odds ratio of 1.10 (95% confidence interval, CI: 1.05 to 1.15) for reporting good self-rated health. By contrast, social participation was associated with a lower odds (0.89, 95% CI: 0.89 to 1.06) of reporting good health.

CONCLUSION

Neighbourhood social cohesion, measured by trust and reciprocity, is associated with higher self-rated health. However, social participation did not appear to be associated with better health in this predominantly low income neighbourhood. These findings provide preliminary support to the relevance for social capital as a determinant of health in Chile.

In vitro somatic embryogenesis and plant regeneration of cassava

An efficient and reproducible plant regeneration system, initiated in somatic tissues, has been devised for cassava (Manihot esculenta Crantz). Somatic embryogenesis has been induced from shoot tips and immature leaves of in vitro shoot cultures of 15 cassava genotypes. Somatic embryos developed directly on the explants when cultured on a medium containing 4-16 mg/l 2,4-D. Differences were observed with respect to the embryogenic capacity of the explants of different varieties. Secondary embryogenesis has been induced by subculture on solid or liquid induction medium. Long term cultures were established and maintained for up to 18 months by repeated subculture of the proliferating somatic embryos. Plantlets developed from primary and secondary embryos in the presence of 0.1 mg/l BAP, 1mg/l GA3, and 0.01 mg/l 2,4-D. Regenerated plants were transferred to the field, and were grown to maturity.