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Acta Diabetologica May 2023To expand the evidence base for the clinical use of metformin, we conducted a meta-analysis of randomized controlled trials (RCTs) comparing the efficacy and safety of... (Meta-Analysis)
Meta-Analysis Review
Short-term neonatal outcomes in women with gestational diabetes treated using metformin versus insulin: a systematic review and meta-analysis of randomized controlled trials.
AIMS
To expand the evidence base for the clinical use of metformin, we conducted a meta-analysis of randomized controlled trials (RCTs) comparing the efficacy and safety of metformin versus insulin with respect to short-term neonatal outcomes.
METHODS
A comprehensive search of electronic databases (PubMed, Embase, Cochrane Library, and Web of Science) was performed. Two reviewers extracted the data and calculated pooled estimates by use of a random-effects model. In total, 24 studies involving 4355 participants met the eligibility criteria and were included in the quantitative analyses.
RESULTS
Unlike insulin, metformin lowered neonatal birth weights (mean difference - 122.76 g; 95% confidence interval [CI] - 178.31, - 67.21; p < 0.0001), the risk of macrosomia (risk ratio [RR] 0.68; 95% CI 0.54, 0.86; p = 0.001), the incidence of neonatal intensive care unit admission (RR 0.73; 95% CI 0.61, 0.88; p = 0.0009), and the incidence of neonatal hypoglycemia (RR 0.65; 95% CI 0.52, 0.81; p = 0.0001). Subgroup analysis based on the maximum daily oral dose of metformin indicated that metformin-induced neonatal birth weight loss was independent of the oral dose.
CONCLUSIONS
Our meta-analysis provides further evidence that metformin is a safe oral antihyperglycemic drug and has some benefits over insulin when used for the treatment of gestational diabetes, without an increased risk of short-term neonatal adverse outcomes. Metformin may be particularly useful in women with gestational diabetes at high risk for neonatal hypoglycemia, women who want to limit maternal and fetal weight gain, and women with an inability to afford or use insulin safely.
Topics: Pregnancy; Infant, Newborn; Female; Humans; Diabetes, Gestational; Metformin; Insulin; Hypoglycemic Agents; Randomized Controlled Trials as Topic; Hypoglycemia; Birth Weight; Weight Gain
PubMed: 36593391
DOI: 10.1007/s00592-022-02016-5 -
Diabetes & Metabolic Syndrome Oct 2022Metformin-treated type 2 diabetes mellitus (T2DM) patients are at higher risk of vitamin B deficiency and more severe neuropathy symptoms. There is still no guideline... (Review)
Review
The efficacy of vitamin B supplementation for treating vitamin B deficiency and peripheral neuropathy in metformin-treated type 2 diabetes mellitus patients: A systematic review.
BACKGROUND AND AIMS
Metformin-treated type 2 diabetes mellitus (T2DM) patients are at higher risk of vitamin B deficiency and more severe neuropathy symptoms. There is still no guideline suggesting vitamin B supplementation for this population. This study aimed to analyze the efficacy of vitamin B supplementation in this population.
METHOD
Studies reporting the efficacy of vitamin B supplementation in metformin-treated T2DM patients were systematically searched in PubMed, Cochrane, EBSCOHost, and Scopus following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Additional relevant studies were searched manually through citations. Study quality and risk of bias were assessed using suitable tools.
RESULTS
Seven clinical trials with a total of 506 participants were included. Using the Cochrane's Risk of Bias 2 tools for clinical trials, 4 studies were assessed to have high risk of bias and 3 studies had low risk of bias. There were 5 studies that measured changes in serum vitamin B level, all of which reported a statistically significant increase after supplementation. Significant reductions in homocysteine after supplementation were found in 2 studies. Its effect on neuropathy symptoms was still unclear, with 2 studies reporting a significant improvement and 1 study reporting no significant effect.
CONCLUSIONS
The results of this systematic review support the implementation of vitamin B supplementation for metformin-treated T2DM to prevent or treat vitamin B deficiency and neuropathy. More high-quality clinical studies are required to generate quantitative analysis and to encourage supplementation in available guidelines.
Topics: Humans; Metformin; Diabetes Mellitus, Type 2; Vitamin B 12; Hypoglycemic Agents; Vitamin B 12 Deficiency; Peripheral Nervous System Diseases; Homocysteine; Dietary Supplements; Vitamins
PubMed: 36240684
DOI: 10.1016/j.dsx.2022.102634 -
Reproductive Biomedicine Online Aug 2019This meta-analysis aimed to evaluate the efficacy and safety of glucagon-like peptide 1 (GLP-1) receptor agonists for women with polycystic ovary syndrome (PCOS) by... (Comparative Study)
Comparative Study Meta-Analysis
This meta-analysis aimed to evaluate the efficacy and safety of glucagon-like peptide 1 (GLP-1) receptor agonists for women with polycystic ovary syndrome (PCOS) by comparing their effect with that of metformin. Electronic databases (PubMed, EMBASE, Cochrane Library, WanFang Database, CNKI) dating from their establishment to June 2018 were searched to find all randomized controlled trials (RCTs) reporting the efficacy of GLP-1 receptor agonists versus metformin for patients with PCOS. Therapeutic variables included menstrual cycle, sex hormone and clinical manifestations, glucose metabolism and other metabolic indexes. Eight RCTs among 462 related articles were included in the meta-analysis. Compared with metformin, GLP-1 receptor agonists were more effective in improving insulin sensitivity (standard mean difference [SMD] -0.40, 95% confidence interval [CI] -0.74 to -0.06, P = 0.02) and reducing body mass index (SMD -1.02, 95% CI -1.85 to -0.19, P = 0.02) and abdominal girth (SMD -0.45, 95% CI -0.89 to -0.00, P = 0.05). GLP-1 receptor agonists were associated with a higher incidence of nausea and headache than metformin, but there were no significant differences in other data. Therefore, compared with metformin, GLP-1 receptor agonists might be a good choice for obese patients with PCOS, especially those with insulin resistance. The available evidence is, however, inconclusive given its moderate to low quality. More high-quality research is needed to assess the efficacy of a GLP-1 receptor agonist on women with PCOS.
Topics: Adult; Androgens; Blood Glucose; Female; Glucagon-Like Peptide-1 Receptor; Homeostasis; Humans; Metformin; Obesity; Polycystic Ovary Syndrome; Randomized Controlled Trials as Topic; Reproducibility of Results; Sample Size; Testosterone; Treatment Outcome; Young Adult
PubMed: 31229399
DOI: 10.1016/j.rbmo.2019.04.017 -
European Review For Medical and... Apr 2021Recent studies have revealed that myo-inositol could be more influential in patients with polycystic ovary syndrome (PCOS). This study was aimed to determine and compare... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
Recent studies have revealed that myo-inositol could be more influential in patients with polycystic ovary syndrome (PCOS). This study was aimed to determine and compare the effects of myo-inositol and metformin on hormonal and metabolic profiles and fertility outcomes.
MATERIALS AND METHODS
A comprehensive search was carried out among the English-language databases, including PubMed, Scopus, Cochrane Library, Google Scholar, and Web of Science, and the articles published from April 2010 to February 2019 were tracked down. The fixed and random-effects meta-analysis was used to estimate the pooled effect size. The meta-analysis was performed in Stata Version 14.0.
RESULTS
Nine studies with 331 patients treated with metformin and 307 patients treated with myo-inositol groups were included in the analysis. The research groups did not diverge significantly in terms of the basic characteristics, such as age and Body Mass Index (BMI). In the myo-inositol group, the levels of Luteinizing Hormone (LH) [12.55% (95% I: 11.41-13.68%)], S. testosterone [44.38% (95% CI: 38.09-50.67%)] and prolactin [7.97% (95% CI: 6.58- 9.37%)] were significantly higher than those recorded, i.e., LH [7.97% (95% CI: 6.58- 9.37%)], S. testosterone [8.48% (95% CI: 3.14-13.83%)] and prolactin [7.14% (95% CI: 1.50-14.79%)] for the metformin group (p<0.001).
CONCLUSIONS
Due to the dearth of related research and the high heterogeneity of the Randomized Clinical Trials (RCTs) included in other studies, the present systematic review could not establish any differences between metformin and myo-inositol concerning the hormonal profile and the ovarian function. However, the findings indicated that myo-inositol could improve fertility outcomes by modulating hyperandrogenism. Randomized trials are required to understand the mechanistic actions of myo-inositol in comparison with those of metformin regarding oocyte and embryo quality, fertilization, pregnancy, and live birth rates.
Topics: Female; Fertilization in Vitro; Humans; Hypoglycemic Agents; Inositol; Metformin; Polycystic Ovary Syndrome
PubMed: 33877679
DOI: 10.26355/eurrev_202104_25565 -
Irish Journal of Medical Science Dec 2023Polycystic Ovary Syndrome is the most prevalent hormonal disorder in females. Over the years, metformin (MET) has become the first-line choice of treatment; however, due... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
Polycystic Ovary Syndrome is the most prevalent hormonal disorder in females. Over the years, metformin (MET) has become the first-line choice of treatment; however, due to its gastrointestinal side effects, a more recent drug, myo-inositol (MI), has been introduced. We aim to conduct a systematic review and meta-analysis to compare the effects of MET and MI on hormonal and metabolic parameters.
MATERIALS AND METHODS
Authors extensively searched PubMed, Scopus, Cochrane Library, Google Scholar, and Web of Science for randomized clinical trials (RCTs) until August 2021. Eight (n = 8) articles were included, with a total sample size of 1088, of which 460 patients received MET, 436 received MI, and 192 received a combination of both. Standard mean differences (SMDs) and Confidence Intervals (CIs) were used for data synthesis, and forest plots were made using Review Manager 5.4 for Statistical Analysis using the random-effect model.
RESULTS
The meta-analysis indicates that there is no significant difference between MET and MI in terms of their effects on BMI (SMD = 0.16, 95% CI: - 0.11 to 0.43, p = 0.24), fasting insulin (SMD = 0.00, 95% CI: - 0.26 to 0.27, p = 0.97), fasting blood sugar (SMD = 0.11, 95% CI: - 0.31to 0.53, p = 0.60), HOMA index (SMD = 0.09, 95% CI: - 0.20 to 0.39, p = 0.50), and LH/FSH (SMD = 0.20, 95% CI: - 0.24 to 0.64, p = 0.37). BMI, fasting blood sugar, and LH/FSH ratio reported moderate heterogeneity because of the varying number of study participants.
CONCLUSION
Our meta-analysis comparing hormonal and metabolic parameters between MET and MI did not show much significant difference, indicating both drugs are equally beneficial in improving metabolic and hormonal parameters in patients with PCOS.
Topics: Female; Humans; Metformin; Polycystic Ovary Syndrome; Hypoglycemic Agents; Blood Glucose; Inositol; Follicle Stimulating Hormone
PubMed: 37148410
DOI: 10.1007/s11845-023-03388-5 -
PLoS Medicine Aug 2019Metformin is increasingly offered as an acceptable and economic alternative to insulin for treatment of gestational diabetes mellitus (GDM) in many countries. However,... (Comparative Study)
Comparative Study Meta-Analysis
BACKGROUND
Metformin is increasingly offered as an acceptable and economic alternative to insulin for treatment of gestational diabetes mellitus (GDM) in many countries. However, the impact of maternal metformin treatment on the trajectory of fetal, infant, and childhood growth is unknown.
METHODS AND FINDINGS
PubMed, Ovid Embase, Medline, Web of Science, ClinicalTrials.gov, and the Cochrane database were systematically searched (from database inception to 26 February 2019). Outcomes of GDM-affected pregnancies randomised to treatment with metformin versus insulin were included (randomised controlled trials and prospective randomised controlled studies) from cohorts including European, American, Asian, Australian, and African women. Studies including pregnant women with pre-existing diabetes or non-diabetic women were excluded, as were trials comparing metformin treatment with oral glucose-lowering agents other than insulin. Two reviewers independently assessed articles for eligibility and risk of bias, and conflicts were resolved by a third reviewer. Outcome measures were parameters of fetal, infant, and childhood growth, including weight, height, BMI, and body composition. In total, 28 studies (n = 3,976 participants) met eligibility criteria and were included in the meta-analysis. No studies reported fetal growth parameters; 19 studies (n = 3,723 neonates) reported measures of neonatal growth. Neonates born to metformin-treated mothers had lower birth weights (mean difference -107.7 g, 95% CI -182.3 to -32.7, I2 = 83%, p = 0.005) and lower ponderal indices (mean difference -0.13 kg/m3, 95% CI -0.26 to 0.00, I2 = 0%, p = 0.04) than neonates of insulin-treated mothers. The odds of macrosomia (odds ratio [OR] 0.59, 95% CI 0.46 to 0.77, p < 0.001) and large for gestational age (OR 0.78, 95% CI 0.62 to 0.99, p = 0.04) were lower following maternal treatment with metformin compared to insulin. There was no difference in neonatal height or incidence of small for gestational age between groups. Two studies (n = 411 infants) reported measures of infant growth (18-24 months of age). In contrast to the neonatal phase, metformin-exposed infants were significantly heavier than those in the insulin-exposed group (mean difference 440 g, 95% CI 50 to 830, I2 = 4%, p = 0.03). Three studies (n = 520 children) reported mid-childhood growth parameters (5-9 years). In mid-childhood, BMI was significantly higher (mean difference 0.78 kg/m2, 95% CI 0.23 to 1.33, I2 = 7%, p = 0.005) following metformin exposure than following insulin exposure, although the difference in absolute weights between the groups was not significantly different (p = 0.09). Limited evidence (1 study with data treated as 2 cohorts) suggested that adiposity indices (abdominal [p = 0.02] and visceral [p = 0.03] fat volumes) may be higher in children born to metformin-treated compared to insulin-treated mothers. Study limitations include heterogeneity in metformin dosing, heterogeneity in diagnostic criteria for GDM, and the scarcity of reporting of childhood outcomes.
CONCLUSIONS
Following intrauterine exposure to metformin for treatment of maternal GDM, neonates are significantly smaller than neonates whose mothers were treated with insulin during pregnancy. Despite lower average birth weight, metformin-exposed children appear to experience accelerated postnatal growth, resulting in heavier infants and higher BMI by mid-childhood compared to children whose mothers were treated with insulin. Such patterns of low birth weight and postnatal catch-up growth have been reported to be associated with adverse long-term cardio-metabolic outcomes. This suggests a need for further studies examining longitudinal perinatal and childhood outcomes following intrauterine metformin exposure. This review protocol was registered with PROSPERO under registration number CRD42018117503.
Topics: Child Development; Child, Preschool; Diabetes, Gestational; Female; Humans; Hypoglycemic Agents; Infant; Infant, Newborn; Insulin; Metformin; Pregnancy
PubMed: 31386659
DOI: 10.1371/journal.pmed.1002848 -
The Journal of Clinical Endocrinology... Jan 2024Polycystic ovary syndrome (PCOS) affects more than 1 in 10 women. (Meta-Analysis)
Meta-Analysis
CONTEXT
Polycystic ovary syndrome (PCOS) affects more than 1 in 10 women.
OBJECTIVE
As part of the 2023 International PCOS Guidelines update, comparisons between combined oral contraceptive pills (COCP), metformin, and combination treatment were evaluated.
DATA SOURCES
Ovid Medline, Embase, PsycINFO, All EBM, and CINAHL were searched.
STUDY SELECTION
Women with PCOS included in randomized controlled trials (RCTs).
DATA EXTRACTION
We calculated mean differences and 95% CIs regarding anthropometrics, metabolic, and hyperandrogenic outcomes. Meta-analyses and quality assessment using GRADE were performed.
DATA SYNTHESIS
The search identified 1660 publications; 36 RCTs were included. For hirsutism, no differences were seen when comparing metformin vs COCP, nor when comparing COCP vs combination treatment with metformin and COCP. Metformin was inferior on free androgen index (FAI) (7.08; 95% CI 4.81, 9.36), sex hormone binding globulin (SHBG) (-118.61 nmol/L; 95% CI -174.46, -62.75) and testosterone (0.48 nmol/L; 95% CI 0.32, 0.64) compared with COCP. COCP was inferior for FAI (0.58; 95% CI 0.36, 0.80) and SHBG (-16.61 nmol/L; 95% CI -28.51, -4.71) compared with combination treatment, whereas testosterone did not differ. Metformin lowered insulin (-27.12 pmol/L; 95% CI -40.65, -13.59) and triglycerides (-0.15 mmol/L; 95% CI -0.29, -0.01) compared with COCP. COCP was inferior for insulin (17.03 pmol/L; 95% CI 7.79, 26.26) and insulin resistance (0.44; 95% CI 0.17, 0.70) compared with combination treatment.
CONCLUSIONS
The choice of metformin or COCP treatment should be based on symptoms, noting some biochemical benefits from combination treatment targeting both major endocrine disturbances seen in PCOS (hyperinsulinemia and hyperandrogenism).
Topics: Female; Humans; Metformin; Polycystic Ovary Syndrome; Contraceptives, Oral, Combined; Hypoglycemic Agents; Testosterone; Insulins
PubMed: 37554096
DOI: 10.1210/clinem/dgad465 -
Frontiers in Endocrinology 2023This study aimed to perform a network meta-analysis to objectively evaluate the efficacy and safety of 10 Glucagon-like peptide-1 receptor agonists (GLP-1RAs) in... (Comparative Study)
Comparative Study Meta-Analysis Review
PURPOSE
This study aimed to perform a network meta-analysis to objectively evaluate the efficacy and safety of 10 Glucagon-like peptide-1 receptor agonists (GLP-1RAs) in combination with metformin that is approved for use worldwide in patients with type 2 diabetes and to provide evidence-based support and reference for the selection of clinical treatment.
METHODS
Three databases (PubMed, Embase, and Cochrane Library) were searched from their respective inception until September 30, 2022. Only randomized controlled trials comparing the efficacy and safety of GLP-1RAs for treating type 2 diabetes (T2D) were included. The 10 GLP-1RAs are exenatide (including exenatide twice daily and once weekly), liraglutide, lixisenatide, dulaglutide, PEX168, semaglutide (subcutaneous and oral semaglutide), tirzepatide and albiglutide.
RESULTS
34 RCTs with 10 GLP-1RAs and 12993 patients were included in the Network Meta-Analysis (NMA). According to the NMA, tirzepatide 15 mg, semaglutide 1.0 mg, PEX168-200μg, oral semaglutide 14 and dulaglutide 1.5 mg reduced HbA1c by -2.23%, -1.57%, -1.12%, -1.10%, -1.09% and body weight by -11.33 kg, -5.99 kg, +0.40 kg, -3.95 kg, -1.87 kg, respectively. There was no significant difference in the rate of adverse events for tirzepatide 15 mg, oral-semaglutide 14 mg, and semaglutide 1.0 mg. PEX168-200μg, tirzepatide 15mg, and oral semaglutide 14mg had Surface Under the Cumulative Ranking (SUCRA) values greater than placebo, and only tirzepatide 15mg and oral semaglutide 14mg were significantly different from placebo in the rate of serious adverse events. All GLP-1RA did not lead to increased incidence of hypoglycemia. Albiglutide 30mg and semaglutide 1.0mg significantly differed from placebo in Adverse Event (AE) withdrawal. Finally, the sensitivity analysis and publication bias analysis results indicate that the study results are reliable.
CONCLUSION
This study's results showed that GLP-1RAs were effective in lowering HbA1c and reducing body weight without increased incidence of hypoglycemic reactions. In addition, this study may provide reference and evidence-based medical evidence for clinicians to select GLP-1RAs in patients with T2D and high body mass index (BMI). Based on the NMA results, tirzepatide 15mg and semaglutide 1.0mg may be preferred.
Topics: Humans; Body Weight; Diabetes Mellitus, Type 2; Exenatide; Glucagon-Like Peptide-1 Receptor; Glycated Hemoglobin; Metformin
PubMed: 37701904
DOI: 10.3389/fendo.2023.1244432 -
The Cochrane Database of Systematic... Oct 2022Antipsychotic-induced weight gain is an extremely common problem in people with schizophrenia and is associated with increased morbidity and mortality. Adjunctive... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Antipsychotic-induced weight gain is an extremely common problem in people with schizophrenia and is associated with increased morbidity and mortality. Adjunctive pharmacological interventions may be necessary to help manage antipsychotic-induced weight gain. This review splits and updates a previous Cochrane Review that focused on both pharmacological and behavioural approaches to this problem.
OBJECTIVES
To determine the effectiveness of pharmacological interventions for preventing antipsychotic-induced weight gain in people with schizophrenia.
SEARCH METHODS
The Cochrane Schizophrenia Information Specialist searched Cochrane Schizophrenia's Register of Trials on 10 February 2021. There are no language, date, document type, or publication status limitations for inclusion of records in the register.
SELECTION CRITERIA
We included all randomised controlled trials (RCTs) that examined any adjunctive pharmacological intervention for preventing weight gain in people with schizophrenia or schizophrenia-like illnesses who use antipsychotic medications.
DATA COLLECTION AND ANALYSIS
At least two review authors independently extracted data and assessed the quality of included studies. For continuous outcomes, we combined mean differences (MD) in endpoint and change data in the analysis. For dichotomous outcomes, we calculated risk ratios (RR). We assessed risk of bias for included studies and used GRADE to judge certainty of evidence and create summary of findings tables. The primary outcomes for this review were clinically important change in weight, clinically important change in body mass index (BMI), leaving the study early, compliance with treatment, and frequency of nausea. The included studies rarely reported these outcomes, so, post hoc, we added two new outcomes, average endpoint/change in weight and average endpoint/change in BMI.
MAIN RESULTS
Seventeen RCTs, with a total of 1388 participants, met the inclusion criteria for the review. Five studies investigated metformin, three topiramate, three H2 antagonists, three monoamine modulators, and one each investigated monoamine modulators plus betahistine, melatonin and samidorphan. The comparator in all studies was placebo or no treatment (i.e. standard care alone). We synthesised all studies in a quantitative meta-analysis. Most studies inadequately reported their methods of allocation concealment and blinding of participants and personnel. The resulting risk of bias and often small sample sizes limited the overall certainty of the evidence. Only one reboxetine study reported the primary outcome, number of participants with clinically important change in weight. Fewer people in the treatment condition experienced weight gains of more than 5% and more than 7% of their bodyweight than those in the placebo group (> 5% weight gain RR 0.27, 95% confidence interval (CI) 0.11 to 0.65; 1 study, 43 participants; > 7% weight gain RR 0.24, 95% CI 0.07 to 0.83; 1 study, 43 participants; very low-certainty evidence). No studies reported the primary outcomes, 'clinically important change in BMI', or 'compliance with treatment'. However, several studies reported 'average endpoint/change in body weight' or 'average endpoint/change in BMI'. Metformin may be effective in preventing weight gain (MD -4.03 kg, 95% CI -5.78 to -2.28; 4 studies, 131 participants; low-certainty evidence); and BMI increase (MD -1.63 kg/m2, 95% CI -2.96 to -0.29; 5 studies, 227 participants; low-certainty evidence). Other agents that may be slightly effective in preventing weight gain include H2 antagonists such as nizatidine, famotidine and ranitidine (MD -1.32 kg, 95% CI -2.09 to -0.56; 3 studies, 248 participants; low-certainty evidence) and monoamine modulators such as reboxetine and fluoxetine (weight: MD -1.89 kg, 95% CI -3.31 to -0.47; 3 studies, 103 participants; low-certainty evidence; BMI: MD -0.66 kg/m2, 95% CI -1.05 to -0.26; 3 studies, 103 participants; low-certainty evidence). Topiramate did not appear effective in preventing weight gain (MD -4.82 kg, 95% CI -9.99 to 0.35; 3 studies, 168 participants; very low-certainty evidence). For all agents, there was no difference between groups in terms of individuals leaving the study or reports of nausea. However, the results of these outcomes are uncertain given the very low-certainty evidence.
AUTHORS' CONCLUSIONS
There is low-certainty evidence to suggest that metformin may be effective in preventing weight gain. Interpretation of this result and those for other agents, is limited by the small number of studies, small sample size, and short study duration. In future, we need studies that are adequately powered and with longer treatment durations to further evaluate the efficacy and safety of interventions for managing weight gain.
Topics: Antipsychotic Agents; Betahistine; Famotidine; Fluoxetine; Humans; Melatonin; Metformin; Nausea; Nizatidine; Ranitidine; Reboxetine; Schizophrenia; Topiramate; Weight Gain
PubMed: 36190739
DOI: 10.1002/14651858.CD013337.pub2 -
The Cochrane Database of Systematic... Nov 2016Child and adolescent obesity has increased globally, and can be associated with significant short- and long-term health consequences. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Child and adolescent obesity has increased globally, and can be associated with significant short- and long-term health consequences.
OBJECTIVES
To assess the efficacy of drug interventions for the treatment of obesity in children and adolescents.
SEARCH METHODS
We searched CENTRAL, MEDLINE, Embase, PubMed (subsets not available on Ovid), LILACS as well as the trial registers ICTRP (WHO) and ClinicalTrials.gov. Searches were undertaken from inception to March 2016. We checked references and applied no language restrictions.
SELECTION CRITERIA
We selected randomised controlled trials (RCTs) of pharmacological interventions for treating obesity (licensed and unlicensed for this indication) in children and adolescents (mean age under 18 years) with or without support of family members, with a minimum of three months' pharmacological intervention and six months' follow-up from baseline. We excluded 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. In addition, we excluded trials which included growth hormone therapies and pregnant participants.
DATA COLLECTION AND ANALYSIS
Two review authors independently assessed trial quality and extracted data following standard Cochrane methodology. Where necessary we contacted authors for additional information.
MAIN RESULTS
We included 21 trials and identified eight ongoing trials. The included trials evaluated metformin (11 trials), sibutramine (six trials), orlistat (four trials), and one trial arm investigated the combination of metformin and fluoxetine. The ongoing trials evaluated metformin (four trials), topiramate (two trials) and exenatide (two trials). A total of 2484 people participated in the included trials, 1478 participants were randomised to drug intervention and 904 to comparator groups (91 participants took part in two cross-over trials; 11 participants not specified). Eighteen trials used a placebo in the comparator group. Two trials had a cross-over design while the remaining 19 trials were parallel RCTs. The length of the intervention period ranged from 12 weeks to 48 weeks, and the length of follow-up from baseline ranged from six months to 100 weeks.Trials generally had a low risk of bias for random sequence generation, allocation concealment and blinding (participants, personnel and assessors) for subjective and objective outcomes. We judged approximately half of the trials as having a high risk of bias in one or more domain such as selective reporting.The primary outcomes of this review were change in body mass index (BMI), change in weight and adverse events. All 21 trials measured these outcomes. The secondary outcomes were health-related quality of life (only one trial reported results showing no marked differences; very low certainty evidence), body fat distribution (measured in 18 trials), behaviour change (measured in six trials), participants' views of the intervention (not reported), morbidity associated with the intervention (measured in one orlistat trial only reporting more new gallstones following the intervention; very low certainty evidence), all-cause mortality (one suicide in the orlistat intervention group; low certainty evidence) and socioeconomic effects (not reported).Intervention versus comparator for mean difference (MD) in BMI change was -1.3 kg/m (95% confidence interval (CI) -1.9 to -0.8; P < 0.00001; 16 trials; 1884 participants; low certainty evidence). When split by drug type, sibutramine, metformin and orlistat all showed reductions in BMI in favour of the intervention.Intervention versus comparator for change in weight showed a MD of -3.9 kg (95% CI -5.9 to -1.9; P < 0.00001; 11 trials; 1180 participants; low certainty evidence). As with BMI, when the trials were split by drug type, sibutramine, metformin and orlistat all showed reductions in weight in favour of the intervention.Five trials reported serious adverse events: 24/878 (2.7%) participants in the intervention groups versus 8/469 (1.7%) participants in the comparator groups (risk ratio (RR) 1.43, 95% CI 0.63 to 3.25; 1347 participants; low certainty evidence). A total 52/1043 (5.0%) participants in the intervention groups versus 17/621 (2.7%) in the comparator groups discontinued the trial because of adverse events (RR 1.45, 95% CI 0.83 to 2.52; 10 trials; 1664 participants; low certainty evidence). The most common adverse events in orlistat and metformin trials were gastrointestinal (such as diarrhoea, mild abdominal pain or discomfort, fatty stools). The most frequent adverse events in sibutramine trials included tachycardia, constipation and hypertension. The single fluoxetine trial reported dry mouth and loose stools. No trial investigated drug treatment for overweight children.
AUTHORS' CONCLUSIONS
This systematic review is part of a series of associated Cochrane reviews on interventions for obese children and adolescents and has shown that pharmacological interventions (metformin, sibutramine, orlistat and fluoxetine) may have small effects in reduction in BMI and bodyweight in obese children and adolescents. However, many of these drugs are not licensed for the treatment of obesity in children and adolescents, or have been withdrawn. Trials were generally of low quality with many having a short or no post-intervention follow-up period and high dropout rates (overall dropout of 25%). Future research should focus on conducting trials with sufficient power and long-term follow-up, to ensure the long-term effects of any pharmacological intervention are comprehensively assessed. Adverse events should be reported in a more standardised manner specifying amongst other things the number of participants experiencing at least one adverse event. The requirement of regulatory authorities (US Food and Drug Administration and European Medicines Agency) for trials of all new medications to be used in children and adolescents should drive an increase in the number of high quality trials.
Topics: Adolescent; Anti-Obesity Agents; Body Mass Index; Child; Cyclobutanes; Fluoxetine; Humans; Lactones; Metformin; Orlistat; Pediatric Obesity; Randomized Controlled Trials as Topic
PubMed: 27899001
DOI: 10.1002/14651858.CD012436