-
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 -
The Science of the Total Environment Jan 2024Prenatal exposure to metal mixtures is associated with adverse pregnancy and birth outcomes like low birth weight, preterm birth, and small for gestational age. However,... (Review)
Review
BACKGROUND
Prenatal exposure to metal mixtures is associated with adverse pregnancy and birth outcomes like low birth weight, preterm birth, and small for gestational age. However, prior studies have used individual metal analysis, lacking real-life exposure scenarios.
OBJECTIVES
This systematic review aims to evaluate the strength and consistency of the association between metal mixtures and pregnancy and birth outcomes, identify research gaps, and inform future studies and policies in this area.
METHODS
The review adhered to the updated Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) checklist, along with the guidelines for conducting systematic reviews and meta-analyses of observational studies of etiology (COSMOS-E). Our data collection involved searching the PubMed, MEDLINE, and SCOPUS databases. We utilized inclusion criteria to identify relevant studies. These chosen studies underwent thorough screening and data extraction procedures. Methodological quality evaluations were conducted using the NOS framework for cohort and case-control studies, and the AXIS tool for cross-sectional studies.
RESULTS
The review included 34 epidemiological studies, half of which focused on birth weight, and the others investigated neonate size, preterm birth, small for gestational age, miscarriage, and placental characteristics. The findings revealed significant associations between metal mixtures (including mercury (Hg), nickel (Ni), arsenic (As), cadmium (Cd), manganese (Mn), cobalt (Co), lead (Pb), zinc (Zn), barium (Ba), cesium (Cs), copper (Cu), selenium (Se), and chromium (Cr)) and adverse pregnancy and birth outcomes, demonstrating diverse effects and potential interactions.
CONCLUSION
In conclusion, this review consistently establishes connections between metal exposure during pregnancy and adverse consequences for birth weight, gestational age, and other vital birth-related metrics. This review further demonstrates the need to apply mixture methods with caution but also shows that they can be superior to traditional approaches. Further research is warranted to deeper understand the underlying mechanisms and to develop effective strategies for mitigating the potential risks associated with metal mixture exposure during pregnancy.
Topics: Female; Humans; Infant, Newborn; Pregnancy; Abortion, Spontaneous; Birth Weight; Cross-Sectional Studies; Fetal Growth Retardation; Mercury; Metals; Placenta; Premature Birth
PubMed: 37963536
DOI: 10.1016/j.scitotenv.2023.168380 -
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 -
Diabetes Care Nov 2023Moderate alcohol use may be associated with lower risk of type 2 diabetes mellitus (T2DM). Previous reviews have reached mixed conclusions. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Moderate alcohol use may be associated with lower risk of type 2 diabetes mellitus (T2DM). Previous reviews have reached mixed conclusions.
PURPOSE
To quantify the dose-response relationship between alcohol consumption and T2DM, accounting for differential effects by sex and BMI.
DATA SOURCES
Medline, Embase, Web of Science, and one secondary data source.
STUDY SELECTION
Cohort studies on the relationship between alcohol use and T2DM.
DATA EXTRACTION
Fifty-five studies, and one secondary data source, were included with a combined sample size of 1,363,355 men and 1,290,628 women, with 89,983 and 57,974 individuals, respectively, diagnosed with T2DM.
DATA SYNTHESIS
Multivariate dose-response meta-analytic random-effect models were used. For women, a J-shaped relationship was found with a maximum risk reduction of 31% (relative risk [RR] 0.69, 95% CI 0.64-0.74) at an intake of 16 g of pure alcohol per day compared with lifetime abstainers. The protective association ceased above 49 g per day (RR 0.82, 95% CI 0.68-0.99). For men, no statistically significant relationship was identified. When results were stratified by BMI, the protective association was only found in overweight and obese women.
LIMITATIONS
Our analysis relied on aggregate data. We included some articles that determined exposure and cases via self-report, and the studies did not account for temporal variations in alcohol use.
CONCLUSIONS
The observed reduced risk seems to be specific to women in general and women with a BMI ≥25 kg/m2. Our findings allow for a more precise prediction of the sex-specific relationship between T2DM and alcohol use, as our results differ from those of previous studies.
Topics: Male; Humans; Female; Diabetes Mellitus, Type 2; Risk Factors; Body Mass Index; Alcohol Drinking; Cohort Studies
PubMed: 37890103
DOI: 10.2337/dc23-1015 -
Obesity Reviews : An Official Journal... Nov 2023Overweight and obesity are consistently associated with lower physical activity (PA) levels and greater sedentary behavior (SB) in population studies. To date, no review... (Review)
Review
Overweight and obesity are consistently associated with lower physical activity (PA) levels and greater sedentary behavior (SB) in population studies. To date, no review has evaluated the factors associated with these behaviors in the specific population who have developed obesity/overweight. The aim of this systematic review was to identify the correlates/determinants of SB and PA in adults with overweight and obesity. Five databases were searched for studies, which reported factors or outcomes relating to PA or SB in adults living with overweight/obesity, published from 1980 to 2021. The factors were categorized using a socioecological model, strength, and direction of association. Of 34,058 articles retrieved, 45 studies were included, and 155 factors were identified. Self-efficacy, intrinsic motivation, exercise enjoyment, self-perceived good health, and social support were consistently associated with higher levels of PA. Consistent negative correlations were married females, increased BMI, obesity severity, pain, number of comorbidities, lack of time, energy, and willpower, and hilly terrain. Few studies (n = 12) examined SB, and no evidence for consistent associations were found. This review identified several correlates specific to PA in this population. Further studies are required to identify directionality and distal correlates for PA and all correlate levels of SB.
Topics: Female; Humans; Adult; Overweight; Sedentary Behavior; Exercise; Obesity; Body Mass Index
PubMed: 37549689
DOI: 10.1111/obr.13615 -
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 -
Clinical Nutrition (Edinburgh, Scotland) Dec 2023Osteoporosis and obesity are closely related, and the relationships between different types of obesity and osteoporosis are inconsistent. (Meta-Analysis)
Meta-Analysis
BACKGROUND
Osteoporosis and obesity are closely related, and the relationships between different types of obesity and osteoporosis are inconsistent.
OBJECTIVE
Our objective was to summarize earlier data concerning the association between osteoporosis and obesity (general and central), and to compare the impacts of these two obesity indicators on osteoporosis.
METHODS
From inception to May 2021, a comprehensive search in electronic bibliographic databases was conducted, and the search was updated in December 2021, July 2022 and June 2023. The data were independently extracted and evaluated by two investigators from epidemiological studies that reported the impact of obesity on the odds of incident osteoporosis.
RESULTS
There were 24 studies included in the final analysis when it came to general obesity measured by body mass index (BMI). Individuals with overweight and obesity had decreased odds of osteoporosis (odds ratio (OR), 0.451, 95% confidence intervals (CIs): 0.366-0.557). Sensitivity analyses showed that both overweight and obesity were decreased odds of osteoporosis, with reductions of 48.6% and 70.1%, respectively (OR, 0.514, 95% CI: 0.407-0.649; OR, 0.299, 95% CI: 0.207-0.433). Conversely, individuals classified as underweight were found to have higher odds of osteoporosis (OR, 2.540, 95% CI: 1.483-4.350). In term of central obesity, the final analysis consisted of 7 studies. No significant association was observed between central obesity and osteoporosis (OR, 0.913, 95% CI: 0.761-1.096).
CONCLUSIONS
General overweight and obesity were associated with lower odds of developing osteoporosis, whereas underweight was associated with higher odds. However, central obesity did not show a significant association with osteoporosis. These findings underscore the importance of considering the impact of obesity on osteoporosis. Further research is necessary to reinforce the evidence and validate our findings.
Topics: Humans; Overweight; Thinness; Obesity, Abdominal; Obesity; Body Mass Index
PubMed: 37925778
DOI: 10.1016/j.clnu.2023.10.013 -
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 -
European Journal of Clinical Nutrition Nov 2023The effect of time-restricted eating (TRE) has been summarized in previous studies, but its benefits in combination with calorie restriction (CR) still need to be... (Meta-Analysis)
Meta-Analysis Review
The effect of time-restricted eating (TRE) has been summarized in previous studies, but its benefits in combination with calorie restriction (CR) still need to be determined. The present meta-analysis aimed to evaluate the efficacy of TRE with CR on weight loss and cardiometabolic risk. PubMed, Embase, Cochrane Library, and gray literature databases were searched from inception to October 18, 2022, for potential randomized controlled trial (RCT) studies based on predefined inclusion and exclusion criteria. Body weight and other cardiometabolic risk factors were described as weighted mean difference (WMD) with a 95% confidence interval (CI). Eight RCTs involving 579 participants were enrolled in the present analysis. The pooled results showed that TRE with CR reduced the body weight, fat mass, and waist circumference significantly (WMD: -1.40, 95% CI: -1.81 to -1.00, and I: 0%; WMD: -0.73, 95% CI: -1.39 to -0.07, and I: 0%; WMD: -1.87, 95% CI: -3.47 to -0.26, and I: 67.25%, respectively). However, compared with CR alone, TRE plus CR exhibited no significant benefit on the blood pressure, glucose profile, and lipid profile. Subgroup analysis suggested that early TRE is more effective in weight loss (WMD: -1.42, 95% CI: -1.84 to -1.01, and I: 0%) and improving fat mass (WMD: -1.06, 95% CI: -1.91 to -0.22, and I: 0%) than delayed or broader TRE when combined with CR. Although the combination of TRE and CR can effectively decrease body weight, fat mass, and waist circumference, the long-term effects, particularly those on cardiometabolic risk in participants with chronic cardiovascular disease and diabetes, remain to be explored.
Topics: Humans; Caloric Restriction; Body Weight; Weight Loss; Cardiovascular Diseases; Blood Pressure
PubMed: 37488260
DOI: 10.1038/s41430-023-01311-w -
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