The Correlation of Prediabetes and Type 2 Diabetes With Adiposity in Adults

The association of thyroid stimulating hormone and body fat in adults

BACKGROUND

Thyroid stimulating hormone (TSH) has been proven to be closely associated with metabolic abnormalities, including obesity. The objective of this investigation was to scrutinize the intricate association between TSH concentration and obesity, within the adult population. The study focused on a comprehensive examination of the relationship, delving into specific adiposity parameters such as total percent fat (TPF), android percent fat (APF), and gynoid percent fat (GPF).

METHODS

This study included 809 participants aged 20 and above with normal TSH values from the National Health and Nutrition Examination Survey (NHANES) 2007-2012. Multivariable linear regression models examined the associations of TSH concentration with TPF, APF, and GPF. Subgroup analyses, stratified by sex, were performed using multivariable linear regression. Fitted smoothing curves and generalized additive models addressed non-linear relationships between TSH and TPF, APF, and GPF.

RESULTS

In fully adjusted models, a significant positive association was observed between TPF and TSH (β = 0.01, 95% CI: 0.00-0.02, p<0.05), while no such association was evident in APF and GPF. Upon sex stratification, females exhibited significant positive correlations between TSH and TPF, APF, and GPF (all p < 0.001), contrasting with males where no such correlations were found. Notably, a non-linear association was identified in males, specifically a U-shaped curve (inflection point: 32.6%) for TSH and APF.

CONCLUSION

The study unveiled a statistically significant positive association between TSH and TPF in adults. Upon sex stratification, similar statistically significant relationships were observed between TSH and adiposity (TPF, APF, GPF) in females, while males exhibited a U-shaped non-linear relationship between TSH and APF.

Personalized Nutrition Therapy without Weight Loss Counseling Produces Weight Loss in Individuals with Prediabetes Who Are Overweight/Obese: A Randomized Controlled Trial

Obesity stands out as a primary risk factor for diabetes. Attaining healthy weight loss, especially reducing body fat, is important in managing prediabetes and preventing progression to full diabetes and its co-morbidities. This study examined the effects of personalized nutrition therapy (PNT) combined with continuous glucose monitoring (CGM) on body weight and composition in individuals with prediabetes. A total of 30 individuals with prediabetes who were overweight or obese were assigned randomly to either the treatment, observed CGM data plus PNT, or the control group which was blinded to their blood glucose results throughout the study. Both groups were provided with dietary recommendations for calorie intake and macronutrient distribution, coupled with personalized goal setting for glucose control and healthy eating, without any specific emphasis on weight reduction or changes in physical activity. Regular visits were scheduled every 10 days to perform measurements and replace CGMs. Data were analyzed using General Linear Model with repeated measures. Over the 30-day follow-up period, both groups experienced significant reductions in weight and fat mass. The treatment group exhibited two-fold greater reductions in both weight and fat mass, a significant decrease in carbohydrate intake, and a significant increase in time spent on physical activitycompared to the control group. In addition, compliance was notably higher in the treatment group. These findings indicate that overweight or obese individuals with prediabetes can achieve weight loss and improved body composition through personalized education for glucose control, without exclusively emphasizing weight loss as the primary objective. Additionally, the real-time feedback provided by CGM enhances these improvements.

Evaluating the effectiveness and safety of various Tirzepatide dosages in the management of Type 2 diabetes mellitus: a network meta-analysis of randomized controlled trials

Purpose

Excess body fat, insulin resistance, and abnormal lipid levels signal type 2 diabetes mellitus (DM2). Globally, 536.6 million people suffer from DM2, projected to rise to 783.2 million by 2045. Obesity fuels insulin resistance and DM2 development, with weight loss significantly improving glycemic control. Titrzepatide (TZP), a dual GIP and GLP-1 receptor agonist, proves highly effective in controlling hyperglycemia, stimulating insulin secretion, and promoting weight loss. TZP, holds promise as a treatment for DM2, surpassing insulin and GLP-1. The study aimed to meticulously assess the safety and efficacy of various doses, offering insights into optimal therapeutic strategies for managing DM2.

Methods

This study aimed to comprehensively evaluate the safety and efficacy of TZP in treating DM2. The primary focus of the inclusion criteria was on trials comparing TZP with a placebo until November 23, 2023, excluding patients with certain comorbidities. Data extraction included key parameters, and outcomes were assessed for HbA1c levels, weight changes, fasting serum glucose levels, and various adverse events. Quality assessment utilized the Cochrane Collaboration's risk-of-bias tool, and a network meta-analysis explored outcomes across different TZP dosages.

Results

This meta-analysis systematically reviewed ten studies on TZP for DM2. Results revealed significant reductions in HbA1c with TZP 10 mg (19%) and TZP 15 mg (31%) compared to TZP 5 mg (MD: -0.19 and MD: -0.32, respectively). Additionally, weight reduction was notable for TZP 10 mg (MD: -1.96) and TZP 15 mg (MD: -3.31). Fasting serum glucose showed improvement with TZP 15 mg (MD:-6.71). Gastrointestinal events increased with higher doses, yet without statistical significance. Death, nausea, diarrhea, vomiting, dyspepsia, decreased appetite, injection site reaction, hypoglycemia, treatment discontinuation, and serious adverse events showed no significant differences across doses.

Conclusion

TZP effectively lowers HbA1c and induces weight loss across its three doses for type 2 diabetes management. The higher dose (15 mg) significantly reduces fasting serum glucose, with increased adverse events observed at higher doses. Dose-specific patterns for adverse effects emphasize the need to balance therapeutic benefits and risks. Further research is crucial for refining clinical applications and understanding TZP's role in DM2 management across doses.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-024-01412-8.

The different association between fat mass distribution and intake of three major nutrients in pre- and postmenopausal women

BACKGROUND

Obesity, characterized by excessive body fat accumulation, is associated with various chronic health conditions. Body fat plays a crucial role in health outcomes, and nutrient intake is a contributing factor. Menopause further influences body fat, but the precise relationships between nutrients and fat mass distribution in pre- and post-menopausal women are unclear.

METHODS

Data from 4751 adult women aged ≥18 years old (3855 pre-menopausal, 896 post-menopausal) with completed information were obtained from the National Health and Examination Survey (NHANES) from 2011 to 2018. Multivariate linear regression models were used to examine the associations between protein, carbohydrate, fat intake and total percent fat (TPF), android percent fat (APF), gynoid percent fat (GPF), android to gynoid ratio (A/G), subcutaneous adipose tissue mass (SAT), visceral adipose tissue mass (VAT). Subgroup analyses, stratified by menopausal status, were also conducted. Additionally, we employed smoothing curve fitting techniques to investigate potential non-linear relationships between fat mass distribution and nutrient intake.

RESULTS

Compared with pre-menopausal women, post-menopausal women had higher body fat, BMI, and metabolic indicators but lower nutrient intake (All p<0.05). In the overall analysis, we found significant correlations between nutrient intake and fat mass. Specifically, protein intake was negatively correlated with TPF (β = -0.017, 95% CI: -0.030, -0.005), APF (β = -0.028, 95% CI: -0.044, -0.012), GPF (β = -0.019, 95% CI: -0.030, -0.008), while fat intake showed positive correlations with these measures (SAT: β = 2.769, 95% CI: 0.860, 4.678). Carbohydrate intake exhibited mixed associations. Notably, body fat mass-nutrient intake correlations differed by menopausal status. Generally speaking, protein intake showed negative correlations with body fat distribution in pre-menopausal women but positive correlations in post-menopausal women. Carbohydrate intake revealed significant negative associations with abdominal and visceral fat in post-menopausal women, while fat intake was consistently positive across all fat distribution indices, especially impacting visceral fat in post-menopausal women.

CONCLUSION

Dietary intake plays a crucial role in body fat distribution, with menopausal status significantly influencing the impact of nutrients on specific fat distribution metrics. The study emphasizes the need for dietary guidelines to consider the nutritional needs and health challenges unique to women at different life stages, particularly concerning menopausal status, to effectively manage obesity.

Evaluation of the relationship of cytokines concentrations tumor necrosis factor-alpha, interleukin-6, and C-reactive protein in obese diabetics and obese non-diabetics: A comparative study

Obesity has been linked to a low-grade inflammatory process in the white adipose tissue. Our study aims to detect the relationship between cytokine levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and C-reactive protein (CRP) in obese diabetics, compared to obese non-diabetics, Iraqi individuals. Ninety Iraqi adults, 45 type 2 diabetic and 45 non-diabetic obese, were selected as controls. Serum levels of TNF-α, IL-6, CRP, homeostatic model assessment for homeostasis model assessment of insulin resistance (HOMA-IR), body fat, and body mass index (BMI) were measured. The concentration of TNF-α, IL-6, and CRP were significantly greater in the obese diabetics, compared to the obese non-diabetics. BMI was significantly positively correlated with the concentration of TNF-α, IL-6, and CRP in the two groups. At the same time, HOMA-IR was non-significantly positively associated with them in obese diabetics. In contrast, the correlation was significantly positive between HOMA-IR with TNF-a, IL-6, and CRP in the obese non-diabetics group. Obese diabetics have more inflammation than obese non-diabetics as evidenced by the former's higher levels of TNF-α and IL-6. Obesity-related imbalances disrupt metabolic processes and increase CRP, TNF-, and IL-6 levels. Therefore, IR is promoted by the increase of cytokines.

The association between prediabetes and bone mineral density: A meta-analysis

BACKGROUND

Prediabetes is an intermediate metabolic state between euglycaemia and diabetes, including three different definitions: impaired fasting glucose, impaired glucose tolerance, and mildly elevated glycated haemoglobin (HbA1c) (range 5.7%-6.4%). The effect of prediabetes on bone mineral density (BMD) has not been established. Therefore, we performed a meta-analysis to evaluate the association between prediabetes and BMD.

METHODS

We retrieved studies related to prediabetes and BMD from PubMed, Web of Science, and Embase databases from January 1990 to December 2022. All data were analysed using the random effects model. Statistical heterogeneity was tested by I2 . Subgroup analysis was performed after each study-level variable was pre-defined by meta-regression.

RESULTS

A total of 17 studies were included involving 45,788 patients. We detected a significant overall association of prediabetes with increased spine BMD (weighted mean difference [WMD] = 0.01, 95% CI [0.00, 0.02], p = 0.005; I2  = 62%), femur neck (FN) BMD (WMD = 0.01, 95% CI [0.00, 0.01], p < 0.001; I2  = 19%), and femur total (FT) BMD (WMD = 0.02, 95% CI [0.01, 0.03], p < 0.001; I2  = 51%). Several variables leading to heterogeneity were defined by meta-regression, including age, sex, region, study type, dual-energy X-ray absorptiometry scanner manufacturer, and prediabetes definition. Subgroup analyses indicated that the association of prediabetes with increased BMD was stronger in men, Asians, and older adults over 60 years of age.

CONCLUSIONS

Current evidence shows that prediabetes is strongly associated with increased BMD of the spine, FN, and FT. The association was stronger among males, Asians, and older adults over 60 years of age.

Comparing Efficacy and Safety of Different Doses of Tirzepatide for the Treatment of Type 2 Diabetes Mellitus: A Meta-Analysis of Randomized Controlled Trials

Our study assessed the efficacy and safety of the three primary tirzepatide (TZP) doses, 5 mg, 10 mg, and 15 mg using network meta-analysis to assess their relative impact on type 2 diabetes mellitus (T2DM) treatment. This study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. Two authors independently screened online databases, including PubMed, Cochrane Library, and Embase. We employed the keywords "Type 2 diabetes OR T2DM or diabetes" AND "Tirzepatide OR LY3298176 OR twincretin OR dual glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist" AND "randomized controlled trial". The outcomes evaluated in this study comprised changes in hemoglobin (Hb)A1c levels from baseline (%), changes in weight from baseline (Kg), changes in fasting serum glucose from baseline (mg/dL), and occurrences of serious adverse events (SAE), adverse events (AE) and major adverse cardiovascular events (MACE). A total of eight studies met the inclusion criteria and were included in this meta-analysis. Our findings suggest that among the evaluated doses, TZP at 15 mg demonstrated superior effectiveness in reducing HbA1c, weight, and fasting serum glucose compared to doses of 10 mg and 5 mg. Notably, the reduction in HbA1c and weight showed a dose-dependent trend, with the 15 mg dose achieving the most substantial benefits. The safety analysis indicated that while serious adverse events and major adverse cardiovascular events (MACE) did not significantly differ among the three doses, the risk of overall adverse events was notably higher in the 10 mg and 15 mg TZP groups compared to the 5 mg group.

Effect of aerobic exercise and low-carbohydrate high-fat diet on glucose tolerance and android/gynoid fat in overweight/obese women: A randomized controlled trial

The study was designed to compare the effects of weight loss induced by a low-carbohydrate-high-fat diet or a normal diet, with and without exercise, on glucose tolerance measured as area under the curve (AUC), and android (A) and gynoid (G) fat distribution. The study was registered at clinicaltrials.gov; NCT04100356. In total, 57 women classified as overweight or obese (age 40 ± 3.5 years, body mass index 31.1 ± 2.6 kg/m²) were randomly assigned and completed a 10-week intervention using a low-carbohydrate high-fat diet or a normal diet, with or without aerobic interval exercise. An equal deficit of 700 kcal/day was prescribed, either restricting the diet only, or moderately restricting diet and including three 50-min high-intensity bicycle sessions per week. There were thus four groups: normal diet (NORM); low-carbohydrate-high-fat diet (LCHF); normal diet with exercise (NORM-EX); and low-carbohydrate-high-fat diet with exercise (LCHF-EX). Linear mixed models was used to assess differences between groups. With all groups pooled, the intervention resulted in a weight loss of 6.7 ± 2.5% (p < 0.001). The intervention did not result in differences between groups in AUC glucose, nor in fasting glucose or indicis for insulin resistance such as Homeostatic Model Assessment, Matsuda Insulin Sensitivity Index, insulinogenic index and disposition index. Post-intervention android fat was lower in LCHF than NORM (3,223 ± 727 vs. 2,533 ± 535 g, p = 0.041). LCHF reached a lower A/G ratio than NORM (0.94 ± 0.12 vs. 1.04 ± 0.09, p = 0.011) and LCHF-EX (0.94 ± 0.12 vs. 1.09 ± 0.09, p < 0.001) after the intervention. LCHF resulted in lower android fat mass compared to NORM and the lowest A/G ratio compared to the other matched groups, but with no accompanying improvement in AUC glucose. In conclusion, although all groups achieved improvements in glucose tolerance, no superior effect was observed with the LCHF diet, neither with nor without exercise.

Testing the Utility of Polygenic Risk Scores for Type 2 Diabetes and Obesity in Predicting Metabolic Changes in a Prediabetic Population: An Observational Study

Prediabetes is an intermediate state of hyperglycemia during which glycemic parameters are above normal levels but below the T2D threshold. T2D and its precursor prediabetes affect 6.28% and 7.3% of the world’s population, respectively. The main objective of this paper was to create and compare two polygenic risk scores (PRSs) versus changes over time (Δ) in metabolic parameters related to prediabetes and metabolic complications. The genetics of 446 prediabetic patients from the Polish Registry of Diabetes cohort were investigated. Seventeen metabolic parameters were measured and compared at baseline and after five years using statistical analysis. Subsequently, genetic polymorphisms present in patients were determined to build a T2D PRS (68 SNPs) and an obesity PRS (21 SNPs). Finally, the association among the two PRSs and the Δ of the metabolic traits was assessed. After a multiple linear regression with adjustment for age, sex, and BMI at a nominal significance of (p < 0.05) and adjustment for multiple testing, the T2D PRS was found to be positively associated with Δ fat mass (FM) (p = 0.025). The obesity PRS was positively associated with Δ FM (p = 0.023) and Δ 2 h glucose (p = 0.034). The comparison of genotype frequencies showed that AA genotype carriers of rs10838738 were significantly higher in Δ 2 h glucose and in Δ 2 h insulin. Our findings suggest that prediabetic individuals with a higher risk of developing T2D experience increased Δ FM, and those with a higher risk of obesity experience increased Δ FM and Δ two-hour postprandial glucose. The associations found in this research could be a powerful tool for identifying prediabetic individuals with an increased risk of developing T2D and obesity.

Digital Single-Image Smartphone Assessment of Total Body Fat and Abdominal Fat Using Machine Learning

Background: Obesity is chronic health problem. Screening for the obesity phenotype is limited by the availability of practical methods. Methods: We determined the reproducibility and accuracy of an automated machine-learning method using smartphone camera-enabled capture and analysis of single, two-dimensional (2D) standing lateral digital images to estimate fat mass (FM) compared to dual X-ray absorptiometry (DXA) in females and males. We also report the first model to predict abdominal FM using 2D digital images. Results: Gender-specific 2D estimates of FM were significantly correlated (p < 0.001) with DXA FM values and not different (p > 0.05). Reproducibility of FM estimates was very high (R2 = 0.99) with high concordance (R2 = 0.99) and low absolute pure error (0.114 to 0.116 kg) and percent error (1.3 and 3%). Bland−Altman plots revealed no proportional bias with limits of agreement of 4.9 to −4.3 kg and 3.9 to −4.9 kg for females and males, respectively. A novel 2D model to estimate abdominal (lumbar 2−5) FM produced high correlations (R2 = 0.99) and concordance (R2 = 0.99) compared to DXA abdominal FM values. Conclusions: A smartphone camera trained with machine learning and automated processing of 2D lateral standing digital images is an objective and valid method to estimate FM and, with proof of concept, to determine abdominal FM. It can facilitate practical identification of the obesity phenotype in adults.

Visceral fat area and body fat percentage measured by bioelectrical impedance analysis correlate with glycometabolism

BACKGROUND

Adiposity evaluated by body mass index (BMI) is associated with glycometabolism. The aim of the investigation was to explore the correlation of visceral fat area (VFA), body fat percentage (BFP), BMI and waist circumference (WC) with type 2 diabetes mellitus (T2DM) and pre-diabetes.

METHODS

A total of 18,458 participates underwent physical examination in Nanjing Drum Tower Hospital from January 2018 to April 2022 was included in this study. Data were collected retrospectively. Regression analysis was used to evaluate the relationship of VFA, BFP, WC and BMI with diabetes status, fasting blood glucose (FBG) and glycohemoglobin (HbA1c).

RESULTS

After fully adjusted for multiple covariates, VFA, BFP, WC and BMI in T2DM and pre-diabetes group exceeded compared with normal group. FBG was positively correlated with VFA, BFP, WC and BMI with βs of 2.221,0.306,0.606 and 0.175(p < 0.001). HbA1c was also positively correlated with the four indexes with βs of 2.645, 0.328, 0.685 and 0.255(p < 0.001). Subgroup analysis shown that FBG and HbA1c were positively correlated with VFA, BFP, BMI and WC in normal and pre-diabetes group (p < 0.001). FBG was negatively correlated with BMI in T2DM group (p = 0.023). In T2DM, there were non-linear relationships of HbA1c with VFA, BFP, WC and BMI with the inflection points for about 7%. Before the inflection point, HbA1c was positively correlated with obesity-related indicators, and it was reversed after the inflection point. In the individuals with excessive VFA and normal BMI, the risk for glycometabolism disorder exceed compared with normal VFA and normal BMI. Every per-standard deviation increasing in VFA, BFP, WC and BMI, the corresponding risk increasing of glycometabolism disorder was 16.4, 14.6, 22.6 and 22.2%.

CONCLUSION

The study demonstrated that in adults with T2DM or prediabetes, the VFA, BFP, WC and BMI were higher than with normal glycometabolism. In pre-diabetes and normal population, there were positive correlations of HbA1c and FBG with obesity-related indicators. In T2DM with poor glycemic control (HbA1c > 7%), there might be a trend of fat loss. VFA could negatively affect glycometabolism independently from BMI. The optimum to evaluate the risk of glycometabolism disorder was WC.

Optimal dose of tirzepatide for type 2 diabetes mellitus: A meta-analysis and trial sequential analysis

Objective

The purpose of this study is to evaluate the optimal dose of tirzepatide (TZP) for the treatment of type 2 diabetes mellitus (T2DM) by meta-analysis and trial sequential analysis (TSA).

Methods

Clinical trials of TZP for T2DM were obtained by searching 8 databases with a time limit from database creation to May 2022. Mean differences (MD) and 95% confidence intervals (95%CI) were used for continuous variables, and relative risk (RR) and 95%CI were used for dichotomous variables.

Results

Compared with TZP 5 mg, meta-analysis showed that TZP 10 mg significantly reduced glycosylated hemoglobin type A1c (HbA1c) (MD −0.24, 95%CI −0.31~-0.17, P &lt; 0.00001), fasting serum glucose (FSG) (MD −5.82, 95%CI −8.35~-3.28, P &lt; 0.00001) and weight (MD −2.47, 95%CI −2.95~-1.98, P &lt; 0.00001), and TZP 15 mg significantly reduced HbA1c (MD −0.37, 95%CI −0.44~-0.29, P &lt; 0.00001), FSG (MD −8.52, 95%CI −11.07~-5.98, P &lt; 0.00001) and weight (MD −4.63, 95%CI −5.45~-3.81, P &lt; 0.00001). Compared with TZP 10 mg, TZP 15 mg dramatically reduced HbA1c (MD −0.12, 95%CI −0.19~-0.05, P = 0.001), FSG (MD −2.73, 95%CI −5.29~-0.17, P = 0.04) and weight (MD −2.18, 95%CI −2.67~-1.70, P &lt; 0.00001). The TSA indicated that the benefits observed in the current information set were conclusive, except for the FSG of “TZP 15 mg vs. TZP 10 mg”. In terms of safety endpoints, meta-analysis revealed that there was no significant difference in the serious adverse events (AEs), major adverse cardiovascular events-4 (MACE-4), cardiovascular death, hypertension, cancer and hypoglycemic of the three dose groups of TZP. Compared with TZP 5 mg, TZP 10 mg increased total adverse events (RR 1.06, 95%CI 1.01~1.11, P = 0.03) and gastrointestinal (GI) AEs (RR 1.17, 95%CI 1.03~1.33, P = 0.02), and TZP 15 mg increased total AEs (RR 1.10, 95%CI 1.05~1.15, P = 0.0001). There were no significant differences in total AEs and GI AEs for TZP 15 mg compared to TZP 10 mg. The TSA demonstrated that the total AEs of “TZP 15 mg vs. TZP 5 mg” were conclusive.

Conclusions

TZP 15 mg &gt;TZP 10 mg &gt; TZP 5 mg in terms of lowering glycemia and reducing weight. TZP 5 mg &gt; TZP 10 mg = TZP 15 mg in terms of safety. On this basis, we recommend TZP 5 mg as the first-choice dose for patients with T2DM to minimize AEs while reducing glycemia and weight. If patients cannot effectively control their glycemia after taking TZP 5 mg, it is recommended to take TZP 15 mg directly to achieve the best effect of glycemic reduction. However, most of the included studies have the background of basic medication, the independent efficacy and safety of different doses of TZP still need to be tested.

Systematic review registration

Unique Identifier: CRD42022341966.