Should metformin be prescribed to overweight adolescents in whom dietary/behavioural modifications have not helped?

Childhood Obesity: An Updated Review

BACKGROUND

Childhood obesity is an important and serious public health problem worldwide.

OBJECTIVE

This article aims to familiarize physicians with the evaluation, management, and prevention of childhood.

METHODS

A PubMed search was conducted in May, 2021, in Clinical Queries using the key terms "obesity" OR "obese". The search included clinical trials, randomized controlled trials, case-control studies, cohort studies, meta-analyses, observational studies, clinical guidelines, case reports, case series, and reviews. The search was restricted to English literature and children. The information retrieved from the above search was used in the compilation of the present article.

RESULTS

Most obese children have exogenous obesity characterized by a growth rate for height above the 50th percentile, normal intelligence, normal genitalia, and lack of historical or physical evidence of an endocrine abnormality or a congenital syndrome. Obese children are at risk for dyslipidemia, hypertension, diabetes mellitus, non-alcoholic fatty liver disease, obstructive sleep apnea, psychosocial disturbances, impaired quality of life, and shorter life expectancy. The multitude of serious comorbidities necessitates effective treatment modalities. Dietary modification, therapeutic exercise, and behavioral modification are the fundamentals of treatment. Pharmacotherapy and/or bariatric surgery should be considered for obese individuals who do not respond to the above measures and suffer from a serious comorbid condition.

CONCLUSION

Childhood obesity, once established, is often refractory to treatment. Most treatment programs lead to a brief period of weight loss, followed by rapid re-accumulation of the lost weight after the termination of therapy. As such, preventive activity is the key to solving the problem of childhood obesity. Childhood obesity can be prevented by promoting a healthy diet, regular physical activity, and lifestyle modification. Parents should be encouraged to get involved in school and community programs that improve their children's nutritional status and physical activity.

WITHDRAWN: Interventions for treating obesity in children

BACKGROUND

Child and adolescent obesity is increasingly prevalent, and can be associated with significant short- and long-term health consequences.

OBJECTIVES

To assess the efficacy of lifestyle, drug and surgical interventions for treating obesity in childhood.

SEARCH METHODS

We searched CENTRAL on The Cochrane Library Issue 2 2008, MEDLINE, EMBASE, CINAHL, PsycINFO, ISI Web of Science, DARE and NHS EED. Searches were undertaken from 1985 to May 2008. References were checked. No language restrictions were applied.

SELECTION CRITERIA

We selected randomised controlled trials (RCTs) of lifestyle (i.e. dietary, physical activity and/or behavioural therapy), drug and surgical interventions for treating obesity in children (mean age under 18 years) with or without the support of family members, with a minimum of six months follow up (three months for actual drug therapy). Interventions that specifically dealt with the treatment of eating disorders or type 2 diabetes, or included participants with a secondary or syndromic cause of obesity were excluded.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data following the Cochrane Handbook. Where necessary authors were contacted for additional information.

MAIN RESULTS

We included 64 RCTs (5230 participants). Lifestyle interventions focused on physical activity and sedentary behaviour in 12 studies, diet in 6 studies, and 36 concentrated on behaviorally orientated treatment programs. Three types of drug interventions (metformin, orlistat and sibutramine) were found in 10 studies. No surgical intervention was eligible for inclusion. The studies included varied greatly in intervention design, outcome measurements and methodological quality.Meta-analyses indicated a reduction in overweight at 6 and 12 months follow up in: i) lifestyle interventions involving children; and ii) lifestyle interventions in adolescents with or without the addition of orlistat or sibutramine. A range of adverse effects was noted in drug RCTs.

AUTHORS' CONCLUSIONS

While there is limited quality data to recommend one treatment program to be favoured over another, this review shows that combined behavioural lifestyle interventions compared to standard care or self-help can produce a significant and clinically meaningful reduction in overweight in children and adolescents. In obese adolescents, consideration should be given to the use of either orlistat or sibutramine, as an adjunct to lifestyle interventions, although this approach needs to be carefully weighed up against the potential for adverse effects. Furthermore, high quality research that considers psychosocial determinants for behaviour change, strategies to improve clinician-family interaction, and cost-effective programs for primary and community care is required.

Pharmacotherapy for obese adolescents

The pharmaceutical search to induce weight loss was precipitated by the United States Food and Drug Administration's (FDA) 1959 formal approval of phentermine for short-term weight loss despite limited research supporting its assertions of weight loss. In addition to sympathomimetic amine products like phentermine, other medications considered in this article include herbal products, sibutramine, orlistat, metformin, and rimonabant. The use of pharmacotherapy for morbidly obese adolescents should be part of a comprehensive weight-loss program that recommends diet, exercise, and behavioral modification. Side effects and the possibility of major adverse effects should be remembered when considering use of these products.

A randomized, triple masked, placebo-controlled clinical trial for controlling childhood obesity

BACKGROUND

The efficacy of pharmacological treatment in controlling childhood obesity is controversial. We aimed to compare the effects of three types of drug regimens and placebo on generalized and abdominal obesity among obese children and adolescents who did not succeed to lose weight 3 months after lifestyle modification (diet and exercise).

METHODS

This triple-masked randomized clinical trial was conducted among 180 participants aged 10-16 years. They were assigned randomly to 4 groups of equal number to receive metformin, fluoxetine, a combination of the two drugs, or placebo. The trial lasted for 12 weeks and participants were followed up for an additional 12-week period.

RESULTS

Overall, 91.1% (n=164) of the enrolled participants completed the trial. After the 12-week trial, the body mass index decreased significantly in all groups receiving medications [approximately -1.2 (0.2) kg/m², P<0.05]. This decrease was not significant in the placebo group. Waist circumference decreased significantly in the groups receiving metformin [-2.1 (0.4) cm, P=0.03)] as well as in the group receiving a combination therapy of metformin and fluoxetine [-2.5 (0.4) cm, P=0.01)]. In the 24-week follow-up study, these anthropometric indexes were lower than the baseline in the group that had received a combination therapy of metformin and fluoxetine. No serious drug side-effects were reported.

CONCLUSIONS

A limited period of such treatment may help weight control, and might be used to encourage those children who have been refractory to weight loss for continuing the non-pharmacological programs. Our findings should be confirmed in future studies with a longer follow-up period.

Changes in weight and metabolic parameters during treatment with antipsychotics and metformin: do the data inform as to potential guideline development? A systematic review of clinical studies

BACKGROUND

Changes in weight and metabolic parameters have been commonly reported in patients with schizophrenia. Metformin has been evaluated in clinical studies to prevent or reduce weight gain and changes in metabolic parameters in non-diabetic subjects. We undertook a systematic review of the efficacy and safety of metformin in reducing weight gain and metabolic abnormalities in non-diabetic subjects with schizophrenia or bipolar disorder taking antipsychotic medication to establish if these data could potentially drive guideline development.

METHODS

Medical databases were searched using terms including 'antipsychotic', 'atypical antipsychotic agent', 'antipsychotic agents', 'antipsychotic-drug' and 'metformin' and 'weight'. Studies reporting weight and/or metabolic outcomes in non-diabetic subjects with schizophrenia and bipolar disorder were included regardless of methodological type and subject age.

RESULTS

Nine randomised double-blind studies and two open cohort studies evaluating metformin and changes in weight in trials up to 16 weeks were identified. In all, 495 participants received antipsychotics (mostly olanzapine), and three studies were in subjects aged < 18 years. The adult studies predominantly utilised non-Caucasian subjects with chronic schizophrenia. Weight and lifestyle intervention programmes were provided to all cohorts in eight studies, which confounded interpretation of the data. In ten studies, the addition of metformin to antipsychotic treatment was associated with either significantly attenuated weight gain or weight loss compared with control groups. Nine studies measured various glucose parameters. In four studies, subjects prescribed metformin had significantly improved glucose parameters relative to controls. The two studies of metformin in patients with first-episode schizophrenia demonstrated the largest improvement in weight and glucose parameters.

CONCLUSIONS

Metformin may have some value in reducing or preventing weight gain and changes in metabolic parameters during treatment with antipsychotic medication particularly in first-episode psychosis; however, it has been predominantly studied short-term and in non-Caucasian populations. A number of new trials are due to report data 2009-2013 to aid definitive interpretation of the role of metformin. Further longer-term studies are warranted before definitive guidelines can be established.

Metformin for weight control in pediatric patients on atypical antipsychotic medication

OBJECTIVE

Metformin was assessed as an interventional medication for weight gain in children and adolescents taking atypical antipsychotic agents.

METHOD

A 12-week open-label trial was conducted to evaluate metformin's effectiveness and safety for weight management. Eleven subjects, ages 10-18 years, participated in the study. Each subject received metformin orally up to 2000 mg/day. Primary outcome measures included weight, body mass index (BMI), and waist circumference. Secondary outcome measures included serum glucose, insulin, and fasting lipid profile. Changes in weight, BMI, waist, and metabolic profile were obtained by using repeated measures of covariance.

RESULTS

The mean reduction in weight, waist, BMI, serum glucose, and serum insulin was not statistically significant. However, 5 out of 11 patients lost weight (mean, -2.82 kg +/- 7.25), and overall the sample did not continue to gain weight. There was a significant decrease in triglyceride levels. Metformin was fairly well tolerated.

CONCLUSION

Preliminary data suggests that metformin may safely and effectively improve the triglyceride profile. However, contrary to study hypotheses, weight, waist, and BMI reduction were not statistically significant. Future double-blind studies with larger sample sizes and of longer duration are warranted to assess more fully the safety and efficacy of this intervention.

Interventions for treating obesity in children

BACKGROUND

Child and adolescent obesity is increasingly prevalent, and can be associated with significant short- and long-term health consequences.

OBJECTIVES

To assess the efficacy of lifestyle, drug and surgical interventions for treating obesity in childhood.

SEARCH STRATEGY

We searched CENTRAL on The Cochrane Library Issue 2 2008, MEDLINE, EMBASE, CINAHL, PsycINFO, ISI Web of Science, DARE and NHS EED. Searches were undertaken from 1985 to May 2008. References were checked. No language restrictions were applied.

SELECTION CRITERIA

We selected randomised controlled trials (RCTs) of lifestyle (i.e. dietary, physical activity and/or behavioural therapy), drug and surgical interventions for treating obesity in children (mean age under 18 years) with or without the support of family members, with a minimum of six months follow up (three months for actual drug therapy). Interventions that specifically dealt with the treatment of eating disorders or type 2 diabetes, or included participants with a secondary or syndromic cause of obesity were excluded.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data following the Cochrane Handbook. Where necessary authors were contacted for additional information.

MAIN RESULTS

We included 64 RCTs (5230 participants). Lifestyle interventions focused on physical activity and sedentary behaviour in 12 studies, diet in 6 studies, and 36 concentrated on behaviorally orientated treatment programs. Three types of drug interventions (metformin, orlistat and sibutramine) were found in 10 studies. No surgical intervention was eligible for inclusion. The studies included varied greatly in intervention design, outcome measurements and methodological quality.Meta-analyses indicated a reduction in overweight at 6 and 12 months follow up in: i) lifestyle interventions involving children; and ii) lifestyle interventions in adolescents with or without the addition of orlistat or sibutramine. A range of adverse effects was noted in drug RCTs.

AUTHORS' CONCLUSIONS

While there is limited quality data to recommend one treatment program to be favoured over another, this review shows that combined behavioural lifestyle interventions compared to standard care or self-help can produce a significant and clinically meaningful reduction in overweight in children and adolescents. In obese adolescents, consideration should be given to the use of either orlistat or sibutramine, as an adjunct to lifestyle interventions, although this approach needs to be carefully weighed up against the potential for adverse effects. Furthermore, high quality research that considers psychosocial determinants for behaviour change, strategies to improve clinician-family interaction, and cost-effective programs for primary and community care is required.

An overview of obesity in children with psychiatric disorders taking atypical antipsychotics

BACKGROUND

Children with psychiatric illness are at greater risk for obesity than those in the general population. In part, this greater risk is due to the escalating use of psychotropic medications. Second-generation antipsychotics effectively treat mental illness but are associated with weight gain. Data for management of obesity in this population is lacking.

METHODS

Articles on obesity, mental illness, and obesity management were reviewed. Keywords included children, adolescents, obesity, weight gain, psychiatric illness, therapy, treatment, and antipsychotic.

RESULTS

For pediatric obesity, educational, nutritional, behavioral, and family-based interventions were identified as nonpharmacological interventions. All nonpharmacological modalities indicate modest to moderate success in weight control or loss. Pharmacological agents, alone or with diet and exercise, appear promising in obesity management.

CONCLUSION

Since there are limited intervention studies available for obese children with psychiatric illness, general childhood obesity studies may be referenced for trials in this population. Long-term efficacy and safety of these interventions are not yet available. Methodological constraints of prior studies include small sample sizes and the absence of randomized, placebo-controlled, and longitudinal trials - highlighting the need for further trials addressing these issues. Clinical monitoring and management of medication-induced obesity remains an important public health concern.

Management approaches for pediatric obesity

Childhood obesity is a worldwide problem that has reached epidemic proportions, resulting in an increased prevalence of premature obesity-related morbidities, and, thus, probable increased health-care costs to treat children. The development of viable approaches to manage this epidemic is crucial. Most experts in the field of childhood obesity agree that the prevention of obesity in children should be the first line of management. Pediatricians must be adept at recognizing children at risk of obesity, calculating and plotting the BMI at all visits, using a change in the BMI to identify excessive weight gain, and monitoring for comorbidities associated with obesity. If obesity is present, the cornerstone of treatment is modification of dietary and exercise habits. Practice-based counseling and community-based programs that support and encourage lifestyle modifications have yielded promising short-term results. Children with severe comorbidities who are unable to achieve lifestyle modifications can be considered for either pharmacologic therapy or surgery, but these options should be considered as a last resort. Early intervention and prevention strategies are the most cost-effective methods of dealing with this issue.