Effects of metformin on body weight and body composition in obese insulin-resistant children: a randomized clinical trial

Unplanned medication discontinuation as a potential pharmacovigilance signal: a nested young person cohort study

Background

Because of relatively small treatment numbers together with low adverse drug reaction (ADR) reporting rates the timely identification of ADRs affecting children and young people is problematic. The primary objective of this study was to assess the utility of unplanned medication discontinuation as a signal for possible ADRs in children and young people.

Methods

Using orlistat as an exemplar, all orlistat prescriptions issued to patients up to 18 years of age together with patient characteristics, prescription duration, co-prescribed medicines and recorded clinical (Read) codes were identified from the Primary Care Informatics Unit database between 1st Jan 2006-30th Nov 2009. Binary logistic regression was used to assess association between characteristics and discontinuation.

Results

During the study period, 79 patients were prescribed orlistat (81% female, median age 17 years). Unplanned medication discontinuation rates for orlistat were 52% and 77% at 1 and 3-months. Almost 20% of patients were co-prescribed an anti-depressant. One month unplanned medication discontinuation was significantly lower in the least deprived group (SIMD 1–2 compared to SIMD 9–10 OR 0.09 (95% CI0.01 – 0.83)) and those co-prescribed at least one other medication. At 3 months, discontinuation was higher in young people (≥17 yr versus, OR 3.07 (95% CI1.03 – 9.14)). Read codes were recorded for digestive, respiratory and urinary symptoms around the time of discontinuation for 24% of patients. Urinary retention was reported for 7.6% of patients.

Conclusions

Identification of unplanned medication discontinuation using large primary care datasets may be a useful tool for pharmacovigilance signal generation and detection of potential ADRs in children and young people.

Metformin in the treatment of obese children and adolescents at risk of type 2 diabetes

Metformin is the first-line treatment for type 2 diabetes (T2D) in adults, children and young people, particularly in obese or overweight patients. Many studies have demonstrated that metformin is associated with weight reduction in adults and in prevention or delay of T2D onset in those who are at increased risk. In 2012, metformin was recommended by the UK National Institute for Health and Care Excellence as a treatment option in adults aged 18 years or over, who remain at high risk of T2D, despite participation in an intensive lifestyle-change programme. Prevalence of childhood obesity is increasing and is associated with elevated long-term risk of T2D and other adverse cardio-metabolic events; however, consensus is lacking on intervention strategies aimed at reducing this risk. This article discusses the rationale and evidence for the use of metformin in obese children and young people at high risk of T2D.

Treatment of obesity-related hypertension in children and adolescents

The obesity epidemic has become a common concern among pediatricians, with an estimated 32 % of US children and adolescents classified as overweight and 18 % as obese. Along with the increase in obesity, a growing body of evidence demonstrates that chronic diseases, such as Type 2 diabetes, primary hypertension, and hyperlipidemia, once thought to be confined solely to adulthood, are commonly seen among the obese in childhood. Following a brief summary of the diagnosis and evaluation of hypertension in obese children and adolescents, this review will highlight recent research on the treatment of obesity-related hypertension. Pharmacologic and non-pharmacologic treatment will be discussed. Additionally, current and emerging therapies for the primary treatment of obesity in children and adolescents, which have been gaining in popularity, will be reviewed.

Obese and overweight children and adolescents: an algorithmic clinical approach

Obesity in children and adolescents is a hot issue throughout the world. Numerous complications are related to childhood obesity, such as cardiovascular disease, diabetes, insulin resistance and psychological problems. Therefore, identification and treatment of this problem have an important role in the health system. In this clinical approach, we have provided a general overview of the assessment and management of obesity in children and adolescents, including definitions, history-taking, physical examinations, and laboratory testing for general practitioners and pediatricians. Furthermore, conventional therapies (physical activity, eating habits and behavioral modification) and non-conventional treatments (drugs and surgery options) have been discussed.

Pregnancy alters choline dynamics: results of a randomized trial using stable isotope methodology in pregnant and nonpregnant women

BACKGROUND

Although biomarkers of choline metabolism are altered by pregnancy, little is known about the influence of human pregnancy on the dynamics of choline-related metabolic processes.

OBJECTIVE

This study used stable isotope methodology to examine the effects of pregnancy on choline partitioning and the metabolic activity of choline-related pathways.

DESIGN

Healthy third-trimester pregnant (n = 26; initially week 27 of gestation) and nonpregnant (n = 21) women consumed 22% of their total choline intake (480 or 930 mg/d) as methyl-d9-choline for the final 6 wk of a 12-wk feeding study.

RESULTS

Plasma d9-betaine:d9-phosphatidylcholine (PC) was lower (P ≤ 0.04) in pregnant than in nonpregnant women, suggesting greater partitioning of choline into the cytidine diphosphate-choline (CDP-choline) PC biosynthetic pathway relative to betaine synthesis during pregnancy. Pregnant women also used more choline-derived methyl groups for PC synthesis via phosphatidylethanolamine N-methyltransferase (PEMT) as indicated by comparable increases in PEMT-PC enrichment in pregnant and nonpregnant women despite unequal (pregnant > nonpregnant; P < 0.001) PC pool sizes. Pregnancy enhanced the hydrolysis of PEMT-PC to free choline as shown by greater (P < 0.001) plasma d3-choline:d3-PC. Notably, d3-PC enrichment increased (P ≤ 0.011) incrementally from maternal to placental to fetal compartments, signifying the selective transfer of PEMT-PC to the fetus.

CONCLUSIONS

The enhanced use of choline for PC production via both the CDP-choline and PEMT pathways shows the substantial demand for choline during late pregnancy. Selective partitioning of PEMT-PC to the fetal compartment may imply a unique requirement of PEMT-PC by the developing fetus.

Position of the Academy of Nutrition and Dietetics: interventions for the prevention and treatment of pediatric overweight and obesity

It is the position of the Academy of Nutrition and Dietetics that prevention and treatment of pediatric overweight and obesity require systems-level approaches that include the skills of registered dietitians, as well as consistent and integrated messages and environmental support across all sectors of society to achieve sustained dietary and physical-activity behavior change. This position paper provides guidance and recommendations for levels of intervention targeting overweight and obesity prevention and treatment from preschool age through adolescence. Methods included a review of the literature from 2009 to April 2012, including the Academy's 2009 evidence analysis school-based reviews. Multicomponent interventions show the greatest impact for primary prevention; thus, early childhood and school-based interventions should integrate behavioral and environmental approaches that focus on dietary intake and physical activity using a systems-level approach targeting the multilevel structure of the socioecological model as well as interactions and relationships between levels. Secondary prevention and tertiary prevention/treatment should emphasize sustained family-based, developmentally appropriate approaches that include nutrition education, dietary counseling, parenting skills, behavioral strategies, and physical-activity promotion. For obese youth with concomitant serious comorbidities, structured dietary approaches and pharmacologic agents should be considered, and weight-loss surgery can be considered for severely obese adolescents. Policy and environmental interventions are recommended as feasible and sustainable ways to support healthful lifestyles for children and families. The Academy supports commitment of resources for interventions, policies, and research that promote healthful eating and physical-activity behaviors to ensure that all youth have the opportunity to achieve and maintain a weight that is optimal for health.

Severe obesity in children and adolescents: identification, associated health risks, and treatment approaches: a scientific statement from the American Heart Association

Severe obesity afflicts between 4% and 6% of all youth in the United States, and the prevalence is increasing. Despite the serious immediate and long-term cardiovascular, metabolic, and other health consequences of severe pediatric obesity, current treatments are limited in effectiveness and lack widespread availability. Lifestyle modification/behavior-based treatment interventions in youth with severe obesity have demonstrated modest improvement in body mass index status, but participants have generally remained severely obese and often regained weight after the conclusion of the treatment programs. The role of medical management is minimal, because only 1 medication is currently approved for the treatment of obesity in adolescents. Bariatric surgery has generally been effective in reducing body mass index and improving cardiovascular and metabolic risk factors; however, reports of long-term outcomes are few, many youth with severe obesity do not qualify for surgery, and access is limited by lack of insurance coverage. To begin to address these challenges, the purposes of this scientific statement are to (1) provide justification for and recommend a standardized definition of severe obesity in children and adolescents; (2) raise awareness of this serious and growing problem by summarizing the current literature in this area in terms of the epidemiology and trends, associated health risks (immediate and long-term), and challenges and shortcomings of currently available treatment options; and (3) highlight areas in need of future research. Innovative behavior-based treatment, minimally invasive procedures, and medications currently under development all need to be evaluated for their efficacy and safety in this group of patients with high medical and psychosocial risks.

Omega-3 polyunsaturated fatty acids reduce insulin resistance and triglycerides in obese children and adolescents

BACKGROUND

Approximately 50% of obese children are insulin resistant. It has been suggested that pharmacological and nutritional options should be considered to improve the management of insulin resistance (IR).

OBJECTIVE

To assess the effect of metformin (Met) or omega-3 (ω-3) polyunsaturated fatty acids (PUFA) on the homeostasis model assessment-estimated insulin resistance (HOMA-IR) index, lipid profile, and body mass index (BMI) of obese children.

METHODS

We included 201 obese and insulin-resistant children and adolescents. Ninety-eight of them received 500 mg of Met, and 103 received 1.8 g of ω-3 PUFA for 12 wk. This was an open-label study with assignment of treatment based on which school the child attended. At the baseline and at the end of study, the following parameters were measured: weight, height, waist circumference, blood pressure, insulin, glucose, lipid profile, and HOMA-IR index. There were no lifestyle interventions.

RESULTS

At baseline, the age, BMI, and IR in children of both groups were comparable. The treatment assigned for each group was well tolerated. Metabolic changes were adjusted for age, sex, and change in BMI. Concerning the IR profile at the end of intervention, ω-3 significantly decreased the concentrations of glucose and insulin while reducing HOMA-IR values; meanwhile, Met negligibly affected insulin levels. Regarding lipids, Met increased high density lipoprotein cholesterol (HDL-C) and decreased low density lipoprotein cholesterol (LDL-C), but triglycerides were not affected; in contrast, triglycerides were decreased significantly by ω-3. The effects on BMI were marginal under Met but were significant with ω-3.

CONCLUSION

The results of this work suggest that ω-3 may be useful as an adjuvant therapy in obese children and adolescents with IR.

The clinical treatment of childhood obesity

With the rising prevalence of childhood obesity, pediatricians are increasingly called upon to treat clinically overweight children. The primary treatment options are behavioral lifestyle modification, pharmacotherapy, and surgery. The cornerstone of childhood obesity treatment is lifestyle modification and has been shown to be effective in improving the severity of overweight and obesity. Several guidelines discuss appropriate methods for lifestyle modification in overweight and obese children. This review will summarize three recent guidelines/recommendations (released by the Scottish Intercollegiate Network, the American Academy of Pediatrics, and the United Kingdom National Institute for Health and Clinical Excellence) and describe by way of example, a current child obesity treatment program in the United States (Duke University Medical Center). Finally, evidence for pharmacologic and surgical treatment options will also be discussed, which can be valuable treatment options for select patients.

Enhancing treatment of obesity by using a distracting mini-meal: a new approach to an old problem

OBJECTIVE

The management of obesity, apart from exercise, mainly involves a calorie restriction regimen. A pharmaceutical treatment is often used to improve patient compliance and diet effectiveness, although several side-effects have previously been described. To improve patient compliance and diet effectiveness without incurring unpleasant side-effects, we evaluated whether a distracting mini-meal can physiologically decrease the absorption of fats and carbohydrates.

DESIGN

Two minutes before each of the three meals consumed daily, 32 obese patients were treated with a distracting mini-meal, 32 with metformin, and 32 with placebo. At baseline and after 1, 3, and 6 months of treatment, body weight, body mass index, waist circumference, fasting/post-prandial insulinaemia and glycaemia, homeostasis model assessment-index, triacylglycerols, and total cholesterol were evaluated.

RESULTS

All patients showed good compliance. With the exception of post-prandial glycaemia, a significant reduction in all parameters was documented in every group, albeit the greater variation was observed in patients treated with a distracting mini-meal or metformin. No one showed noteworthy side-effects.

CONCLUSIONS

Our study focuses on a distracting mini-meal that could become a useful tool in enhancing weight loss. The beneficial effect of a distracting meal on insulin resistance, glucose, and lipid metabolism suggest its possible use to prevent or mitigate obesity-related disorders.

Childhood obesity for pediatric gastroenterologists

Obesity in childhood is one of the major health issues in pediatric health care today. As expected, the prevalence of obesity-related comorbidities has risen in parallel with that of obesity. Consultation regarding these concomitant diseases and subsequent management by subspecialists, including pediatric gastroenterologists, is now common and has resulted in obesity being recognized as a chronic disease requiring coordination of care. Although medications and even surgery may provide effective, though often temporary, treatments for obesity and its comorbidities, behavioral interventions addressing healthy dietary and physical activity habits remain a mainstay in the obesity treatment paradigm. Therefore, the issue of weight management must be addressed by both general practitioner and subspecialist alike. In this report, we review select aspects of pediatric obesity and obesity-related management issues because it relates in particular to the field of pediatric gastroenterology and hepatology.

Metformin in obese children and adolescents: the MOCA trial

CONTEXT

Childhood obesity is increasingly associated with type 2 diabetes (T2D). Metformin reduces the risk for T2D in adult obese nondiabetic patients, but the evidence in obese children and young people is inconclusive.

OBJECTIVE

The objective of the study was to assess the effect of metformin on body mass index sd score (BMI-SDS), metabolic risk factors, and adipokines.

DESIGN

This was a prospective, randomized, double-blind, placebo-controlled trial.

SETTING

The study was conducted at six pediatric endocrine centers in the United Kingdom.

PARTICIPANTS

One hundred fifty-one obese children and young people with hyperinsulinemia and/or impaired fasting glucose or impaired glucose tolerance (metformin: 74, placebo: 77). The study was comprised of 67.5% females, 65.6% postpubertal individuals, and 23.8% British Asian or Afro-Caribbean participants. The age range was 8-18 yr, the mean age was 13.7 (SD 2.3) yr, and the mean BMI-SDS was +3.4 (SD 0.5).

INTERVENTIONS

The intervention included metformin 1 g in the morning and 500 mg in the evening vs. placebo for 6 months.

MAIN OUTCOME MEASURE

The main outcome measure was a reduction in BMI-SDS at 6 months. Secondary outcomes included insulin and glucose levels from oral glucose tolerance tests, alanine aminotransferase (ALT), and adiponectin to leptin ratio (ALR) at 3 and 6 months.

RESULTS

Metformin was associated with a significant reduction in BMI-SDS compared with placebo at 6 months [mean difference -0.1 SD (95% confidence interval -0.18 to -0.02), P = 0.02]. Significant improvements at 3 months were found in the metformin group: fasting glucose, -0.16 mmol/liter (-0.31 to -0.00), P = 0.047; ALT, 19% (5-36%), P = 0.008; and ALR, 32% (4-67%), P = 0.02.

CONCLUSIONS

Metformin therapy has a beneficial treatment effect over placebo for BMI-SDS, fasting glucose, ALT, and ALR ratio at 3 months, with changes in BMI-SDS sustained at 6 months.

Pharmacotherapy for childhood obesity: present and future prospects

Pediatric obesity is a serious medical condition associated with significant comorbidities during childhood and adulthood. Lifestyle modifications are essential for treating children with obesity, yet many have insufficient response to improve health with behavioral approaches alone. This review summarizes the relatively sparse data on pharmacotherapy for pediatric obesity and presents information on obesity medications in development. Most previously studied medications demonstrated, at best, modest effects on body weight and obesity-related conditions. It is to be hoped that the future will bring new drugs targeting specific obesity phenotypes that will allow clinicians to use etiology-specific, and therefore more effective, anti-obesity therapies.

Pigment epithelium-derived factor increases in type 2 diabetes after treatment with metformin

OBJECTIVE

Pigment epithelium-derived factor (PEDF) has anti-angiogenic, immunomodulatory and anti-inflammatory properties. In addition to the significant role it plays in reducing diabetic complications, PEDF is now used in the treatment of certain cancers. It possibly plays a role in insulin resistance cases, too. However, whether metformin treatment has any significant effects on PEDF levels is not known. In this study, we investigated the regulation of PEDF in type 2 diabetes in relation to fat mass and insulin resistance before and after the use of metformin for treatment.

DESIGN

Prospective cohort study.

SUBJECTS

Thirty-six patients with newly diagnosed type 2 diabetes and 33 healthy individuals.

MEASUREMENTS

Baseline weight, waist circumference (WC), fasting (FPG) and postprandial (PPPG) glucose, insulin, HbA1c, HOMA, PEDF and total/truncal fat mass were determined both in the diabetic and control subjects. Procedures were repeated in the diabetic group after a 6-month metformin treatment.

RESULTS

Baseline FPG, PPPG, HbA1c, HOMA, weight, WC and truncal fat mass were higher in patients with diabetes whereas PEDF levels were found to be comparable with the controls. We completed the study with 31 of the 36 patients with diabetes we had selected for the study. We observed a decrease in the weight, WC, FPG, PPPG, HOMA, total and truncal fat mass of the patients while there was a significant rise in the PEDF levels (P = 0·002) after the metformin treatment. On the other hand, no significant correlation was observed between the change in PEDF levels and the clinical and laboratory findings.

CONCLUSION

Our study is the first to identify a metformin-related increase in PEDF levels in diabetes. The increase observed in PEDF levels after the metformin treatment does not seem to be related to the changes in insulin resistance, fat mass or glycemic control. Hence, our results suggest that further investigation is necessary to determine the direct effects of metformin on PEDF gene and protein expression in vitro.

Metformin and its clinical use: new insights for an old drug in clinical practice

Metformin is generally recommended as first-line treatment in type 2 diabetes, especially in overweight patients, but in recent years new indications for its use have emerged. Metformin has been found to be safe and efficacious both as monotherapy and in combination with all oral antidiabetic agents and insulins. If metformin use during pregnancy and the lactation period is supported by few data, it could be indicated for women with polycystic ovary syndrome, since it could diminish circulating androgens and insulin resistance, thus ameliorating the ovulation rate. Metformin seems to reduce cancer risk, which appears to be increased in diabetics, and is a promising agent for oncoprevention and chemotherapy combinations. Moreover, metformin could find a place in the treatment of non-alcoholic fatty liver disease. Lactic acidosis could be decreased by avoiding metformin use in patients with hypovolemia, sepsis, renal impairment, hypoxic respiratory diseases and heart failure, in the preoperative period and before intravenous injection of contrast media.

Assessment of metformin as an additional treatment to therapeutic lifestyle changes in pediatric patients with metabolic syndrome

Objective. To assess the effectiveness of metformin and therapeutic lifestyle changes (TLCs) in a clinical setting, compared to TLC alone in adolescents with metabolic syndrome (MS). Methodology. This study was a retrospective trial consisting of 60 patients, aged 8–18 years, who were treated for MS at an outpatient clinic. Two groups were formed: the metformin group (M group) and the control group (C group). The M group had been given metformin along with TLC, and the C group had been given TLC alone. Several outcome measures were obtained; the main outcome measure was measuring the change in percentile and z-score of weight and BMI. Results. There were no significant differences between the two groups at the conclusion of the study, except for height percentile (P = 0.02) and z-score (P = 0.03). Both groups showed promising significant intragroup decreases in weight z-score but BMI percentile and z-score were only significantly decreased in the M group. Conclusion. Metformin at an average dose of 1033 mg, when added to TLC, did not show any clinically important efficacy compared to TLC alone in a pediatric population with MS. However, both groups made significant changes in a positive direction, which may be solely due to TLC.

Metformin in obesity, cancer and aging: addressing controversies

Metformin, an oral anti-diabetic drug, is being considered increasingly for treatment and prevention of cancer, obesity as well as for the extension of healthy lifespan. Gradually accumulating discrepancies about its effect on cancer and obesity can be explained by the shortage of randomized clinical trials, differences between control groups (reference points), gender- and age-associated effects and pharmacogenetic factors. Studies of the potential antiaging effects of antidiabetic biguanides, such as metformin, are still experimental for obvious reasons and their results are currently ambiguous. Here we discuss whether the discrepancies in different studies are merely methodological or inherently related to individual differences in responsiveness to the drug.

Long-term safety, tolerability, and weight loss associated with metformin in the Diabetes Prevention Program Outcomes Study

OBJECTIVE

Metformin produced weight loss and delayed or prevented diabetes in the Diabetes Prevention Program (DPP). We examined its long-term safety and tolerability along with weight loss, and change in waist circumference during the DPP and its long-term follow-up.

RESEARCH DESIGN AND METHODS

The randomized double-blind clinical trial of metformin or placebo followed by a 7-8-year open-label extension and analysis of adverse events, tolerability, and the effect of adherence on change in weight and waist circumference.

RESULTS

No significant safety issues were identified. Gastrointestinal symptoms were more common in metformin than placebo participants and declined over time. During the DPP, average hemoglobin and hematocrit levels were slightly lower in the metformin group than in the placebo group. Decreases in hemoglobin and hematocrit in the metformin group occurred during the first year following randomization, with no further changes observed over time. During the DPP, metformin participants had reduced body weight and waist circumference compared with placebo (weight by 2.06 ± 5.65% vs. 0.02 ± 5.52%, P < 0.001, and waist circumference by 2.13 ± 7.06 cm vs. 0.79 ± 6.54 cm, P < 0.001 in metformin vs. placebo, respectively). The magnitude of weight loss during the 2-year double-blind period was directly related to adherence (P < 0.001). Throughout the unblinded follow-up, weight loss remained significantly greater in the metformin group than in the placebo group (2.0 vs. 0.2%, P < 0.001), and this was related to the degree of continuing metformin adherence (P < 0.001).

CONCLUSIONS

Metformin used for diabetes prevention is safe and well tolerated. Weight loss is related to adherence to metformin and is durable for at least 10 years of treatment.

Exenatide as a weight-loss therapy in extreme pediatric obesity: a randomized, controlled pilot study

The objective of this pilot study was to evaluate the effects of exenatide on BMI (primary endpoint) and cardiometabolic risk factors in nondiabetic youth with extreme obesity. Twelve children and adolescents (age 9-16 years old) with extreme obesity (BMI ≥1.2 times the 95th percentile or BMI ≥35 kg/m(2)) were enrolled in a 6-month, randomized, open-label, crossover, clinical trial consisting of two, 3-month phases: (i) a control phase of lifestyle modification and (ii) a drug phase of lifestyle modification plus exenatide. Participants were equally randomized to phase-order (i.e., starting with control or drug therapy) then crossed-over to the other treatment. BMI, body fat percentage, blood pressure, lipids, oral glucose tolerance tests (OGTT), adipokines, plasma biomarkers of endothelial activation, and endothelial function were assessed at baseline, 3-, and 6-months. The mean change over each 3-month phase was compared between treatments. Compared to control, exenatide significantly reduced BMI (-1.7 kg/m(2), 95% confidence interval (CI) (-3.0, -0.4), P = 0.01), body weight (-3.9 kg, 95% CI (-7.11, -0.69), P = 0.02), and fasting insulin (-7.5 mU/l, 95% CI (-13.71, -1.37), P = 0.02). Significant improvements were observed for OGTT-derived insulin sensitivity (P = 0.02) and β-cell function (P = 0.03). Compliance with the injection regimen was excellent (≥94%) and exenatide was generally well-tolerated (the most common adverse event was mild nausea in 36%). These preliminary data suggest that exenatide should be evaluated in larger, well-controlled trials for its ability to reduce BMI and improve cardiometabolic risk factors in youth with extreme obesity.

Treatment of obesity in children and adolescents

The prevalence of childhood and adolescent obesity continues to rise in the United States (US). Immediate health consequences are being observed, and long-term risks are mounting within the pediatric population, secondary to obesity. The hallmark of prevention and treatment of obesity in children and adolescents includes lifestyle modification (i.e., dietary modification, increased physical activity, and behavioral modifications). However, when intensive lifestyle modification is insufficient to reach weight loss goals, adjunctive pharmacotherapy is recommended. Among the group of weight-loss medications, orlistat is the only US Food and Drug Administration (FDA)-approved prescription drug for the treatment of overweight and obese adolescents. Other medications, including metformin, need larger studies to establish their role in treatment. No single approach to management of pediatric obesity is the answer, given the complexity of the disorder and the many reasons for failure. Evidence of weight loss medications in addition to lifestyle modification supports short-term efficacy for treatment of obese children and adolescents, although long-term results remain unclear.

Metformin use in children with obesity and normal glucose tolerance--effects on cardiovascular markers and intrahepatic fat

OBJECTIVE

To determine if metformin improves markers of inflammation, thrombosis, and intrahepatic fat contents in children with uncomplicated obesity.

METHODS

Obese children with normal glucose tolerance but elevated highly sensitive C-reactive protein (hsCRP) and/or fibrinogen concentrations (>2 standard deviations) were randomized to structured diet/exercise or diet/exercise and metformin for 6 months. Blood samples, dual energy X-ray absorptiometry data, and liver magnetic resonance images were obtained.

RESULTS

Forty-two of 66 recruited children (7-18 years) completed 6 months. Weight loss was modest but more pronounced in the metformin group (-4.9 +/- 1.0 kg) than in the diet/exercise group (-1.7 +/- 1.1 kg, p<0.03), whereas hsCRP and fibrinogen decreased more in the diet/exercise pubertal group. Baseline intrahepatic fat was high but decreased only in the diet/exercise (not metformin) pubertal group.

CONCLUSIONS

Six months of metformin therapy improved weight loss and reduced abdominal adiposity, but did not enhance the beneficial effect of diet and exercise on markers related to inflammation, thrombosis, or hepatic fat in obese children with normal glucose tolerance.

Diabetes and insulin resistance in pediatric obesity

Over the past 2 decades, the prevalence of obesity and type 2 diabetes mellitus (T2DM) in children and adolescents has risen to epidemic proportions and disproportionately affects racial and ethnic minorities, who are at greater risk. The pathophysiology of T2DM is complex and involves insulin resistance, pancreatic β-cell dysfunction, and visceral adiposity. Current treatments of T2DM are limited to lifestyle intervention, metformin, and insulin therapy; use of these strategies in combination is often most effective. The role of research is to uncover simple biomarkers for insulin sensitivity and optimal and innovative treatment of insulin resistance and T2DM.

Assessment and management of obesity in childhood and adolescence

The increased prevalence of obesity in childhood and adolescence highlights the need for effective treatment approaches. Initial assessments of these patients should include taking a careful history (investigating comorbidities, family history and potentially modifiable behaviors) and physical examination with BMI plotted on a BMI-for-age chart. The degree of investigation is dependent on the patient's age and severity of obesity, the findings on history and physical examination, and associated familial risk factors. There are several broad principles of conventional management: management of comorbidities; family involvement; taking a developmentally appropriate approach; the use of a range of behavior change techniques; long-term dietary change; increased physical activity; and decreased sedentary behaviors. Orlistat can be useful as an adjunct to lifestyle changes in severely obese adolescents and metformin can be used in older children and adolescents with clinical insulin resistance. Bariatric surgery should be considered in those who are severely obese, with recognition of the need for management in centers with multidisciplinary weight management teams and for surgery to be performed in tertiary institutions experienced in bariatric surgery. Finally, given the high prevalence and chronic nature of obesity, coordinated models of care for health-service delivery for the management of pediatric obesity are needed.

Assessment and management of obesity in childhood and adolescence

The increased prevalence of obesity in childhood and adolescence highlights the need for effective treatment approaches. Initial assessments of these patients should include taking a careful history (investigating comorbidities, family history and potentially modifiable behaviors) and physical examination with BMI plotted on a BMI-for-age chart. The degree of investigation is dependent on the patient's age and severity of obesity, the findings on history and physical examination, and associated familial risk factors. There are several broad principles of conventional management: management of comorbidities; family involvement; taking a developmentally appropriate approach; the use of a range of behavior change techniques; long-term dietary change; increased physical activity; and decreased sedentary behaviors. Orlistat can be useful as an adjunct to lifestyle changes in severely obese adolescents and metformin can be used in older children and adolescents with clinical insulin resistance. Bariatric surgery should be considered in those who are severely obese, with recognition of the need for management in centers with multidisciplinary weight management teams and for surgery to be performed in tertiary institutions experienced in bariatric surgery. Finally, given the high prevalence and chronic nature of obesity, coordinated models of care for health-service delivery for the management of pediatric obesity are needed.

Pediatric obesity: etiology and treatment

This article reviews factors that contribute to excessive weight gain in children and outlines current knowledge regarding approaches for treating pediatric obesity. Most of the known genetic causes of obesity primarily increase energy intake. Genes regulating the leptin signaling pathway are particularly important for human energy homeostasis. Obesity is a chronic disorder that requires long-term strategies for management. The foundation for all treatments for pediatric obesity remains restriction of energy intake with lifestyle modification. There are few long-term studies of pharmacotherapeutic interventions for pediatric obesity. Bariatric surgical approaches are the most efficacious treatment but, because of their potential risks, are reserved for those with the most significant complications of obesity.