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Cardiovascular Diabetology Nov 2023There is uncertainty regarding the role of obesity in type 1 diabetes development. The aim of this systematic review and meta-analysis was to collect and synthesize... (Meta-Analysis)
Meta-Analysis
BACKGROUND
There is uncertainty regarding the role of obesity in type 1 diabetes development. The aim of this systematic review and meta-analysis was to collect and synthesize evidence regarding BMI and the risk of developing type 1 diabetes.
METHODS
A systematic review and meta-analysis were conducted to assess the association between BMI and incident type 1 diabetes. Databases were searched up to June 2022. Cohort studies were included reporting the association between overweight and/or obesity, as measured by BMI after age 2 years, with incident type 1 diabetes. Independent reviewers extracted data and assessed study quality. Risk estimates were pooled using a random-effects model.
RESULTS
Ten cohort studies met the inclusion criteria. The seven studies that classified BMI into categories were of high quality and involved 1,690,660 individuals and 1979 incident type 1 diabetes cases. The pooled risk ratio (RR) for type 1 diabetes was 1.35 (95% CI 0.93-1.97) among people with overweight (3 studies); 2.17 (95% CI 1.75-2.69) among people with obesity (5 studies); and 1·87 (95% CI 1.52-2.29) among people with overweight/obesity (two studies merged the categories). These point estimates persisted in sensitivity analyses that addressed the duration of follow-up, variability in baseline risk for incident type 1 diabetes, and potential misclassifications related to exposure or outcome definitions. People with overweight/obesity had a 2.55 (95% CI 1.11-5.86) greater risk for incident type 1 diabetes with positive islet autoantibodies.
CONCLUSION
This systematic review and meta-analysis of high-quality observational cohort studies indicated an association between high BMI and the risk of type 1 diabetes, in a graded manner.
Topics: Humans; Child, Preschool; Overweight; Diabetes Mellitus, Type 1; Body Mass Index; Obesity; Cohort Studies
PubMed: 37919779
DOI: 10.1186/s12933-023-02007-y -
International Journal of Obesity (2005) Feb 2024Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are potentially obesogenic for children. We undertook a systematic review to synthesize this literature and explore... (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are potentially obesogenic for children. We undertook a systematic review to synthesize this literature and explore sources of heterogeneity in previously published epidemiological studies.
METHODS
Studies that collected individual-level PFAS and anthropometric data from children up to 12 years of age were identified by searching six databases. We excluded studies that only evaluated obesity measures at the time of birth. A full-text review and quality assessment of the studies was performed using the Office of Health Assessment and Translation (OHAT) criteria. Forest plots were created to summarize measures of association and assess heterogeneity across studies by chemical type and exposure timing. Funnel plots were used to assess small-study effects.
RESULTS
We identified 24 studies, of which 19 used a cohort design. There were 13 studies included in the meta-analysis examining various chemicals and outcomes. Overall prenatal exposures to four different types of PFAS were not statistically associated with changes in body mass index (BMI) or waist circumference. In contrast, for three chemicals, postnatal exposures were inversely related to changes in BMI (i.e., per log10 increase in PFOS: BMI z-score of -0.16 (95% CI: -0.22, -0.10)). There was no substantial heterogeneity in the reported measures of association within prenatal and postnatal subgroups. We observed modest small-study effects, but correction for these effects using the Trim and Fill method did not change our summary estimate(s).
CONCLUSION
Our review found no evidence of a positive association between prenatal PFAS exposure and pediatric obesity, whereas an inverse association was found for postnatal exposure. These findings should be interpreted cautiously due to the small number of studies. Future research that can inform on the effects of exposure mixtures, the timing of the exposure, outcome measures, and the shape of the exposure-response curve is needed.
Topics: Pregnancy; Child; Female; Humans; Pediatric Obesity; Body Mass Index; Fluorocarbons; Environmental Pollutants
PubMed: 37907715
DOI: 10.1038/s41366-023-01401-6 -
Journal of the Academy of Nutrition and... Feb 2024Avocados are a rich source of unsaturated fats and bioactives, however, their role in altering cardiometabolic risk factors is unclear. (Meta-Analysis)
Meta-Analysis
BACKGROUND
Avocados are a rich source of unsaturated fats and bioactives, however, their role in altering cardiometabolic risk factors is unclear.
OBJECTIVE
The aim was to review the effects of consuming diets containing avocado compared with control diets containing no or low amounts of avocado on cardiometabolic risk factors in adults who were healthy, had clinical cardiovascular disease, or were at increased risk of cardiovascular disease.
METHODS
Five electronic databases were searched (PubMed, Web of Science, Scopus, ProQuest, and a Clinical Trials Registry) along with Google Scholar to identify studies published between January 1990 and November 10, 2021. Randomized controlled trials ≥3 weeks and prospective cohort studies were included. Ten studies-9 randomized controlled trials (n = 503 participants) and 1 prospective observational study (n = 55,407)-met the inclusion criteria. Outcomes assessed by means of meta-analysis were low-density lipoprotein cholesterol (LDL-C) (primary), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and triglycerides. Outcomes assessed by narrative review were TC to HDL-C ratio, non-HDL-C, apolipoprotein B, blood pressure, body weight, body mass index (calculated as kg/m), waist circumference, waist-to-hip ratio, body composition, and blood glucose and insulin concentrations. Risk of bias was assessed using the Cochrane Risk of Bias tool, version 2.0 and Newcastle-Ottawa Scale; quality of evidence was examined using the Grading of Recommendations, Assessment, Development and Evaluation method. Random-effects models meta-analyses were performed when there were ≥3 studies of the same design (ie, randomized controlled trial) and reporting the same outcome. Statistical heterogeneity was assessed by calculating χ and I statistics and publication bias was assessed by funnel plots.
RESULTS
Overall, there was a small, significant reduction in TC (-5.08 mg/dL [to convert to mmol/L, divide by 38.67]; 95% CI -9.29 to -0.87 mg/dL; P = .02) in avocado vs the control groups and no significant difference in LDL-C, HDL-C, or triglycerides. Subgroup analysis demonstrated significant reductions in LDL-C (-9.4 mg/dL [to convert to mmol/L, divide by 38.67]; 95% CI -10.84 to -7.95 mg/dL; P < .00001) and TC (-7.54 mg/dL; 95% CI -9.40 to -5.68 mg/dL; P < .00001) in avocado vs control groups in hypercholesterolemic populations, and no differences were seen in normocholesterolemic populations. However, the certainty in the findings was graded as low to very low. Body weight and composition were not negatively affected by avocado consumption.
CONCLUSIONS
Avocado consumption may reduce TC and LDL-C in people with hypercholesterolemia. Avocado consumption does not negatively impact body weight. Larger, well-conducted studies are needed to have greater confidence in the role of avocado consumption on cardiovascular disease risk factors.
Topics: Adult; Humans; Persea; Cardiovascular Diseases; Cholesterol, LDL; Prospective Studies; Cholesterol; Triglycerides; Body Weight; Cholesterol, HDL; Observational Studies as Topic
PubMed: 36565850
DOI: 10.1016/j.jand.2022.12.008 -
Pharmacological Research Jan 2024As new antidiabetic drugs, tirzepatide (Tir) and semaglutide (Sem) are progressively applied in clinical practice. However, their efficacy and safety profiles have not... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
As new antidiabetic drugs, tirzepatide (Tir) and semaglutide (Sem) are progressively applied in clinical practice. However, their efficacy and safety profiles have not been comprehensively assessed. Therefore, a Bayesian network meta-analysis was used to evaluate and compare the efficacy and safety of Tir and Sem in treating type 2 diabetes mellitus (T2DM).
METHODS
PubMed, EMBASE, Web of Science, Cochrane Library and ClinicalTrials.gov were systematically searched from inception to April 3rd, 2023. Randomized clinical trials (RCTs) comparing the efficacy and safety of Tir and Sem with placebo or the other antidiabetic drugs in treating T2DM were included. The efficacy outcomes included changes in glycated hemoglobin (HbA1c), body weight (BW), body mass index (BMI), and the proportion of participants with HbA1c< 7 %. The safety outcome was the proportion of participants experiencing gastrointestinal adverse events (GIAEs).
RESULTS
A total of 38 studies involving 34,166 participants were included. Compared to 1 mg of subcutaneous Sem (Sem SC), 5 mg, 10 mg and 15 mg of Tir demonstrated superior efficacy in reducing HbA1c (mean difference (MD), [95 % CI], -0.22 [-0.40, -0.03] %, -0.42 [-0.60, -0.24] % and -0.53 [-0.71, -0.35] %, respectively) and BW (MD [95 % CI], -1.48 [-2.53, -0.43] kg, -4.00 [-5.05, -2.95] kg and -5.71 [-6.73, -4.68] kg, respectively). Conversely, 7 mg and 14 mg of oral Sem (Sem PO) displayed inferior efficacy in reducing HbA1c (MD [95 % CI], 0.47 [0.26, 0.68] % and 0.35 [0.16, 0.54] %, respectively) and BW (MD [95 % CI], 2.36 [1.24, 3.48] kg and 1.11 [0.10, 2.13] kg). However, 20 mg and 40 mg of Sem PO were non-inferior in reducing HbA1c (MD [95 % CI], 0.13 [-0.29, 0.55] % and 0.01 [-0.38, 0.40] %, respectively) and BW (MD [95 % CI], -0.41 [-2.71, 1.90] kg and -1.32 [-3.58, 0.92] kg). In terms of safety, compared to 1 mg of Sem SC, 5 mg, 10 mg and 15 mg of Tir did not significantly increase the incidence of GIAEs (odd ratio (OR) [95 % CI], 0.70 [0.42, 1.10], 0.87 [0.52, 1.36] and 0.99 [0.60, 1.54], respectively), while 7 mg of Sem PO showed a lower incidence of GIAEs (OR [95 % CI], 0.48 [0.25, 0.83]). Compared to insulin, 0.5 mg of Sem SC, 1 mg of Sem SC, 5 mg of Tir, 10 mg of Tir and 15 mg of Tir displayed better efficacy in lowering HbA1c (MD [95 % CI], -0.40 [-0.63, -0.18] %, -0.69 [-0.90, -0.48] %, -0.91 [-1.10, -0.72] %, -1.11 [-1.30, -0.92] % and -1.22 [-1.41, -1.03] %, respectively) and BW (MD [95 % CI], -5.34[-6.60, -4.09] kg, -6.70 [-7.90,-5.51] kg, -8.18 [-9.27, -7.10] kg, -10.70 [-11.79, -9.61] kg and -12.41 [-13.49,-11.33] kg, respectively). According to the surface under the cumulative ranking curve (SUCRA) value, among all the included interventions, 15 mg of Tir exhibited the most potent effect in reducing HbA1c (99.81 %) and BW (99.98 %), followed by 10 mg of Tir (96.83 % and 95.72 %), 5 mg of Tir (92.88 % and 86.04 %), 1 mg of Sem SC (85.85 % and 74.97 %), 40 mg of Sem PO (83.66 % and 84.31 %), 20 mg of Sem PO (76.98 % and 77.12 %), 300 mg of Can (49.93 % and 60.89 %), insulin (36.38 % and 0.22 %) and 100 mg of Sit (12.28 % and 18.51 %) respectively. Meanwhile, 5 mg, 10 mg, and 15 mg of Tir (48.32 %, 30.96 %, and 21.07 %, respectively), 0.5 mg and 1 mg of Sem SC (33.54 % and 24.77 %, respectively) significantly increased the incidence of GIAEs.
CONCLUSION
Both Tir and Sem demonstrated favorable antidiabetic effects and were particularly suitable for T2DM patients who were obese or overweight. Despite a high incidence of GIAEs, their safety profile was deemed acceptable. Tir was the best option among all the included interventions.
Topics: Humans; Body Weight; Diabetes Mellitus, Type 2; Gastric Inhibitory Polypeptide; Glucagon-Like Peptide-2 Receptor; Glucagon-Like Peptides; Glycated Hemoglobin; Hypoglycemic Agents; Insulin; Network Meta-Analysis
PubMed: 38061595
DOI: 10.1016/j.phrs.2023.107031 -
Acta Obstetricia Et Gynecologica... Dec 2023The association between extreme birth spacing and adverse outcomes is controversial, and available evidence is fragmented into different classifications of birth spacing. (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
The association between extreme birth spacing and adverse outcomes is controversial, and available evidence is fragmented into different classifications of birth spacing.
MATERIAL AND METHODS
We conducted a systematic review of observational studies to evaluate the association between birth spacing (i.e., interpregnancy interval and interoutcome interval) and adverse outcomes (i.e., pregnancy complications, adverse birth outcomes). Pooled odds ratios (ORs) with 95% confidence intervals (CI) were calculated using a random-effects model, and the dose-response relationships were evaluated using generalized least squares trend estimation.
RESULTS
A total of 129 studies involving 46 874 843 pregnancies were included. In the general population, compared with an interpregnancy interval of 18-23 months, extreme intervals (<6 months and ≥ 60 months) were associated with an increased risk of adverse outcomes, including preterm birth, small for gestational age, low birthweight, fetal death, birth defects, early neonatal death, and premature rupture of fetal membranes (pooled OR range: 1.08-1.56; p < 0.05). The dose-response analyses further confirmed these J-shaped relationships (p < 0.001-0.009). Long interpregnancy interval was only associated with an increased risk of preeclampsia and gestational diabetes (p < 0.005 and p < 0.001, respectively). Similar associations were observed between interoutcome interval and risk of low birthweight and preterm birth (p < 0.001). Moreover, interoutcome interval of ≥60 months was associated with an increased risk of cesarean delivery (pooled OR 1.72, 95% CI 1.04-2.83). For pregnancies following preterm births, an interpregnancy interval of 9 months was not associated with an increased risk of preterm birth, according to dose-response analyses (p = 0.008). Based on limited evidence, we did not observe significant associations between interpregnancy interval or interoutcome interval after pregnancy losses and risk of small for gestational age, fetal death, miscarriage, or preeclampsia (pooled OR range: 0.76-1.21; p > 0.05).
CONCLUSIONS
Extreme birth spacing has extensive adverse effects on maternal and infant health. In the general population, interpregnancy interval of 18-23 months may be associated with potential benefits for both mothers and infants. For women with previous preterm birth, the optimal birth spacing may be 9 months.
Topics: Pregnancy; Infant; Infant, Newborn; Humans; Female; Pregnancy Outcome; Premature Birth; Birth Intervals; Pre-Eclampsia; Birth Weight; Abortion, Spontaneous; Pregnancy Complications; Fetal Growth Retardation; Mothers; Fetal Death
PubMed: 37675816
DOI: 10.1111/aogs.14648 -
Acta Obstetricia Et Gynecologica... Aug 2023Exposures in utero are suggested to play a role in the etiology of endometriosis and adenomyosis, although the current evidence is inconclusive. Knowledge about... (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
Exposures in utero are suggested to play a role in the etiology of endometriosis and adenomyosis, although the current evidence is inconclusive. Knowledge about potential prenatal programming and early life exposures that may affect this risk is of high importance, to focus potential preventive strategies for the diseases already during pregnancy. The aim of this study was to review systematically the literature of the association between measures of fetal growth and preterm birth and endometriosis and adenomyosis in adult life.
MATERIAL AND METHODS
A systematic review according to Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines and by search on PubMed and EMBASE was carried out. We included published case-control and cohort studies. We excluded studies without a reference group, eg case series, case reports as well as commentaries, letters and editorials. The quality of the studies was assessed using the Newcastle-Ottawa Scale. Meta-analyses using a random-effect inverse variance weighted model were performed. PROSPERO registration number is CRD42021249322.
RESULTS
A total of 11 studies were included. In general, the quality scores of the studies were moderate. We found that the risk of endometriosis was 26% higher in women born with a birthweight <2.5 kg (pooled odds ratio [pOR] 1.26, 95% confidence interval [CI] 1.05-1.52) and 32% higher in women born preterm (pOR 1.32, 95% CI 1.01-1.72) than in the reference groups. The studies on adenomyosis pointed towards no association, but a meta-analysis was unfeasible due to the small number of studies.
CONCLUSIONS
This systematic review and meta-analysis found that low birthweight and being born preterm were associated with endometriosis in adult life, but the results must be interpreted cautiously. No solid conclusion could be made regarding adenomyosis due to a limited number of published studies, but the studies included found no association. The results support the hypothesis of a potential early programming effect of endometriosis. However, the body of evidence is sparse and this hypothesis needs to be investigated further.
Topics: Pregnancy; Infant, Newborn; Female; Adult; Humans; Premature Birth; Endometriosis; Birth Weight; Adenomyosis; Fetal Development
PubMed: 37475152
DOI: 10.1111/aogs.14594 -
BMC Endocrine Disorders Jul 2023Childhood obesity is one of the main concerns of public health. Considering its long-term adverse health effect, various studies investigated the effect of drug therapy... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Childhood obesity is one of the main concerns of public health. Considering its long-term adverse health effect, various studies investigated the effect of drug therapy on anthropometric parameters and provided mixed results. In this systematic review and meta-analysis, we aimed to determine the effect of Orlistat on anthropometrics and biochemical parameters in children and adolescents.
MATERIALS AND METHODS
The databases of PubMed, Scopus, and Web of Science were searched until September 2022. Experimental and semi-experimental studies were included if they evaluated the effect of Orlistat on obesity-related parameters in children and reported the before and after anthropometric values. A revised Cochrane risk-of-bias (Rob2) was used to evaluate the methodological quality. STATA software version 16.0 was used for the meta-analysis of the random-effect model.
RESULTS
Of 810 articles retrieved in the initial search, four experimental and two semi-experimental studies were selected for systematic review. The result of the meta-analysis of experimental studies indicated the significant effect of Orlistat on waist circumference (SMD: -0.27, 95% CI: -0.47, -0.07) and serum insulin level (SMD: -0.89, 95% CI: -1.52, 0.26). However, there were no significant effects of orlistat on body weight, body mass index, lipid profile, and serum glucose level.
CONCLUSION
The present meta-analysis showed the significant effect of Orlistat on the reduction of waist circumference and insulin level in overweight and obese adolescents. However, due to the paucity of studies included in the meta-analysis, more prospective studies with longer duration and more sample sizes will be needed in this age group.
Topics: Child; Adolescent; Humans; Orlistat; Anti-Obesity Agents; Prospective Studies; Pediatric Obesity; Lactones; Insulins
PubMed: 37420181
DOI: 10.1186/s12902-023-01390-7 -
Journal of the International Society of... Dec 2023Reference values of body fat for competitive volleyball players are lacking, making it difficult to interpret measurement results. This review systematically summarized... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Reference values of body fat for competitive volleyball players are lacking, making it difficult to interpret measurement results. This review systematically summarized published data on the relative body fat of volleyball players and calculated potential differences between sex, measurement method, and competitive level.
METHODS
The protocol followed the Preferred Reported Items for Systematic Reviews and Meta-Analysis guidelines. The literature search was conducted using five electronic databases to retrieve all relevant publications from January 1, 2010, to July 1, 2021. The 63 studies including 2607 players that met the inclusion criteria were analyzed using random-effects models. Data were reported as pooled mean body fat with 95% confidence intervals.
RESULTS
Body fat for males and females was 12.8% (11.9-13.8%) and 22.8% (21.9-23.7%), respectively. Body fat was 18.3% (16.3-20.4%) measured via skinfolds, 18.4% (15.6-21.2%) via bioelectrical impedance analysis, 24.2% (20.4-28.0%) via dual-energy x-ray absorptiometry and 21.6% (17.4-25.8%) via densitometry. Regional, national, and international-level players had body fat values of 19.5% (17.8-21.2%), 20.3% (18.6-22.0%), and 17.9% (15.7-20.4%), respectively. When the meta-regression was adjusted for the variables sex, measurement method, and competitive level, a significant difference between sex ( < 0.001), dual-energy x-ray absorptiometry and skinfolds ( = 0.02), and national and international-level players ( = 0.02) was found. However, sensitivity analysis revealed that findings regarding measurement method and competitive level were not robust and should, therefore, be interpreted with caution.
CONCLUSIONS
Despite the limitations of published data, this meta-analysis provided pooled values for body fat of male and female volleyball players for different competitive levels and measurement methods.
Topics: Humans; Male; Female; Volleyball; Body Composition; Anthropometry; Adipose Tissue; Absorptiometry, Photon
PubMed: 37578094
DOI: 10.1080/15502783.2023.2246414 -
Hua Xi Kou Qiang Yi Xue Za Zhi = Huaxi... Aug 2023To evaluate the effects of a Twin-block appliance on the condyles of patients with ClassⅡmalocclusion by conducting a systematic review and a Meta-analysis. (Meta-Analysis)
Meta-Analysis
OBJECTIVES
To evaluate the effects of a Twin-block appliance on the condyles of patients with ClassⅡmalocclusion by conducting a systematic review and a Meta-analysis.
METHODS
Pubmed, Embase, Cochrane Library, Chinese BioMedical Literature Database, China National Knowledge Infrastructure, and VIP Database were electronically searched. Randomized controlled trials, controlled clinical trials, and single-arm trials on condylar changes produced by a Twin-block appliance in patients with ClassⅡmalocclusion were included. Two reviewers independently extracted and assessed the risk of bias. Meta-analyses were conducted with Review Manager 5.3.
RESULTS
Eight studies were included; among which, seven were of high quality. After treatment with a twin block appliance, condyles moved anteriorly. The anterior joint spaces decreased (<0.000 01), whereas the posterior spaces increased (<0.000 01). The superior spaces were not changed (=0.11). Moreover, a significant difference was observed in the increase of the condylar space index (<0.000 01). After treatment, the anteroposterior diameters of the condyles and condylar height increased (=0.000 2 and <0.000 01, respectively). By contrast, no significant changes were discovered in the medial external diameters of the condyles (=0.42).
CONCLUSIONS
A Twin-block appliance can promote the growth of a condyle in the posterior and upper direction and move it forward in favor of the correction of Class Ⅱ malocclusion.
Topics: Humans; Malocclusion, Angle Class II; Temporomandibular Joint; Bone and Bones; China; Orthodontic Appliances, Functional; Cephalometry
PubMed: 37474479
DOI: 10.7518/hxkq.2023.2023052 -
Frontiers in Endocrinology 2023The aim of present meta-analysis was to determine the effects of exercise training (Exe) on insulin resistance (IR) and body weight in children and adolescents with... (Meta-Analysis)
Meta-Analysis
AIM
The aim of present meta-analysis was to determine the effects of exercise training (Exe) on insulin resistance (IR) and body weight in children and adolescents with overweight or obesity.
METHODS
PubMed, Web of Science, and Scopus were searched for original articles, published through October 2022 that included exercise versus control interventions on fasting glucose, insulin, HOMA-IR, and body weight outcomes in children and adolescents with overweight or obesity. Standardized mean differences (SMD) for fasting insulin, and weighted mean differences (WMD) for fasting glucose, HOMA-IR, body weight (BW), and 95% confidence intervals were determined using random effects models.
RESULTS
Thirty-five studies comprising 1,550 children and adolescents with overweight and obesity were included in the present meta-analysis. Exercise training reduced fasting glucose (WMD=-2.52 mg/dL, p=0.001), fasting insulin (SMD=-0.77, p=0.001), HOMA-IR (WMD=-0.82, p=0.001), and BW (WMD=-1.51 kg, p=0.001), as compared to a control. Subgroup analyses showed that biological sex, intervention duration, type of exercise training, BMI percentile, and health status (with or without diagnosed condition), were sources of heterogeneity.
CONCLUSION
Exercise training is effective for lowering fasting glucose, fasting insulin, HOMA-IR, and BW in children and adolescents with overweight or obesity and could provide an important strategy for controlling IR and related factors. With clear evidence for the effectiveness of exercise interventions in this vulnerable population, it is important to determine effective approaches for increasing exercise training in children and adolescents with overweight or obesity.
Topics: Adolescent; Child; Humans; Body Weight; Exercise; Glucose; Insulin; Insulin Resistance; Overweight; Pediatric Obesity
PubMed: 37635963
DOI: 10.3389/fendo.2023.1178376