Screening for a Simple and Effective Indicator of Insulin Resistance in Chinese Reproductive-Aged Women, with the Insulin Clamp Technique as a Reference

Lipid accumulation product and visceral adiposity index for incidence of cardiovascular diseases and mortality; results from 13 years follow-up in Isfahan cohort study

Background

/Aims: Visceral adiposity index (VAI) and lipid accumulation product (LAP) are novel anthropometric indices that have shown an association with metabolic syndrome; however, limited data are available regarding the predictive performance of these indices for the incidence of cardiovascular diseases (CVD) and mortality.

Methods

This study was performed on the data retrieved from Isfahan Cohort Study (ICS). ICS is an ongoing population-based cohort study conducted in 3 counties in central Iran. Pearson correlation analysis was performed between LAP, VAI, and metabolic parameters. Cox regression analysis and receiver operative characteristics (ROC) curve analysis were performed in order to evaluate the ability of VAI and LAP for the incidence of CVD, CVD-associated mortality, and all-cause mortality. We further compared the predictive performance of VAI and LAP with body mass index (BMI).

Results

LAP and VAI were significantly correlated with all metabolic variables, including blood pressure, fasting blood glucose, and lipid profile components. Univariate regression analysis indicated a significant association between LAP and VAI and CVD incidence. In multivariate analysis, only VAI was significantly associated with CVD incidence. Regarding CVD mortality, only VAI in the multivariate analysis revealed a significant association. Interestingly, Both VAI and LAP were negatively associated with all-cause mortality. ROC curve analysis indicated the superior performance of LAP and VAI for predicting CVD incidence compared to BMI; however, BMI was better in predicting all-cause mortality.

Conclusion

Compared to BMI, LAP and VAI have better predictive performance for the incidence of CVD. In contrast, BMI was superior to VAI and LAP in the prediction of all-cause mortality.

Comparison of seven surrogate insulin resistance indexes for prediction of incident coronary heart disease risk: a 10-year prospective cohort study

Background

There were seven novel and easily accessed insulin resistance (IR) surrogates established, including the Chinese visceral adiposity index (CVAI), the visceral adiposity index (VAI), lipid accumulation product (LAP), triglyceride glucose (TyG) index, TyG-body mass index (TyG-BMI), TyG-waist circumference (TyG-WC) and TyG-waist to height ratio (TyG-WHtR). We aimed to explore the association between the seven IR surrogates and incident coronary heart disease (CHD), and to compare their predictive powers among Chinese population.

Methods

This is a 10-year prospective cohort study conducted in China including 6393 participants without cardiovascular disease (CVD) at baseline. We developed Cox regression analyses to examine the association of IR surrogates with CHD (hazard ratio [HR], 95% confidence intervals [CI]). Moreover, the receiver operating characteristic (ROC) curve was performed to compare the predictive values of these indexes for incident CHD by the areas under the ROC curve (AUC).

Results

During a median follow-up period of 10.25 years, 246 individuals newly developed CHD. Significant associations of the IR surrogates (excepted for VAI) with incident CHD were found in our study after fully adjustment, and the fifth quintile HRs (95% CIs) for incident CHD were respectively 2.055(1.216-3.473), 1.446(0.948-2.205), 1.753(1.099-2.795), 2.013(1.214-3.339), 3.169(1.926-5.214), 2.275(1.391-3.719) and 2.309(1.419-3.759) for CVAI, VAI, LAP, TyG, TyG-BMI, TyG-WC and TyG-WHtR, compared with quintile 1. Furthermore, CVAI showed maximum predictive capacity for CHD among these seven IR surrogates with the largest AUC: 0.632(0.597,0.667).

Conclusion

The seven IR surrogates (excepted for VAI) were independently associated with higher prevalence of CHD, among which CVAI is the most powerful predictor for CHD incidence in Chinese populations.

Accuracy of visceral adiposity indices and lipid accumulation products in the identification of adults at high cardiovascular risk

INTRODUCTION

The lipid accumulation product (LAP) and visceral adipose index (VAI) are clinical markers of visceral obesity and were proposed as simple tools to estimate cardiovascular risk and mortality. The objective of this study was to analyze the accuracy of the VAI and LAP for high cardiovascular risk patients.

METHODS

A cross-sectional observational study of accuracy was carried out in 193 patients of both sexes. In addition to the variables VAI and LAP, presence of comorbidities, education, level of physical activity and anthropometric data were obtained. Cardiovascular risk was determined by the Framingham score.

RESULTS

No significant difference was observed in the sample in gender distribution (44.6% women; 55.4% men), 24.4% had low cardiovascular risk, 48.7% intermediate risk and 26.9% high cardiovascular risk. Linear regression analysis showed that VAI and LAP explain, respectively, only 2.4% and 5.2% of the variation in cardiovascular risk expressed by the Framingham score. The analysis of areas under the curve (AUC) for receiver operating characteristic (ROC) indicated a significant effect only of LAP to diagnose individuals with high cardiovascular risk, but with low sensitivity and specificity.

CONCLUSION

Our results indicate that VAI and LAP explain only a small percentage of the variation in the Framingham cardiovascular risk score. LAP index still deserves more attention in a cohort study, because, even with the limitations of a cross-sectional study, we observed an acceptable sensitivity for it so that the LAP can be used as a screening criterion for requesting more accurate tests.

Comparison of six surrogate insulin resistance indexes for predicting the risk of incident stroke: The Rural Chinese Cohort Study

BACKGROUND AND PURPOSE

Some cheap and easily used operated indexes of insulin resistance (IR) were currently available. We aimed to evaluate the association of six surrogate indexes of IR with incident stroke and to compare their predictive capacity.

METHODS

We analysed data from 14,595 eligible study participants from the Rural Chinese Cohort Study. Modified Poisson regression models were used to estimate relative risks (RRs) and 95% confidence intervals (95% CIs) of incident stroke associated with the visceral adiposity index (VAI), the Chinese visceral adiposity index (CVAI), lipid accumulation product (LAP), triglyceride-glucose (TyG), TyG-body mass index, and TyG-waist circumference. The receiver operator characteristic curve was used to compare the ability of the abovementioned IR indexes to predict stroke.

RESULTS

During a median follow-up of 6 years, 786 newly diagnosed stroke cases were identified. The levels of six surrogate indexes of IR were all significantly higher in the stroke population than in the non-stroke population (p < 0.001). Compared with quartile 1, the multivariable adjusted RRs (95% CIs) of incident stroke for quartile 4 were 2.01 (1.47-2.76), 1.62 (1.28, 2.04), 1.64 (1.28-2.09), and 1.92 (1.50-2.45) for CVAI, VAI, LAP, and TyG, respectively. Significant dose-response associations were also found between surrogate IR indexes and risk of stroke. The area under the curves|areas under the curves for CVAI (0.674) was significantly greater than for other indexes (TyG-WC:0.622, TyG:0.614, LAP:0.606, TyG-BMI:0.598, and VAI:0.577) (p < 0.001).

CONCLUSIONS

Six surrogate indexes of IR were independently associated with incident stroke. The CVAI may be the most suitable index for stroke prediction.

Cardiovascular Risk According to Body Mass Index in Women of Reproductive Age With Polycystic Ovary Syndrome: A Systematic Review and Meta-Analysis

Background

Polycystic ovary syndrome (PCOS) is a heterogeneous condition that affects women of reproductive age. The association between PCOS and cardiovascular risk according to body mass index (BMI) categories is unclear.

Objective

We evaluated the association between cardiovascular risk according to BMI categories and PCOS in women of reproductive age.

Methods

A literature search was conducted in the EMBASE, MEDLINE, Cochrane Library, and PubMed databases from their inception to 9 September, 2021. Observational cross-sectional, retrospective, and prospective controlled studies were included. The main analyses examined the relationship between cardiovascular risks (i.e., blood pressure and lipid levels) and BMI in women of reproductive age with PCOS.

Results

Thirty-eight studies, with a total of 6,078 subjects, were included in this metaanalysis. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were higher in women of reproductive age with PCOS. Lower high-density lipoprotein (HDL)-cholesterol [SMD (95% CI): −0.21 (−0.35, −0.08), p = 0.002], higher triglycerides [SMD (95% CI): 0.38 (0.29, 0.48), p < 0.001], higher low-density lipoprotein (LDL)-cholesterol [SMD (95% CI): 0.29 (0.20, 0.39), p < 0.001], higher nonHDL-cholesterol [SMD (95% CI): 0.42 (0.31, 0.52), p < 0.001] and waist-to-hip ratio (WHR) [MD (95% CI): 0.03 (0.02, 0.04), p < 0.001] were seen in women of reproductive age with PCOS. In addition, the subgroup analysis revealed that systolic BP and HDL-cholesterol increased at BMI < 25 kg/m² and BMI 25–30 kg/m². Diastolic BP increased at BMI 25–30 kg/m². Triglycerides, LDL-cholesterol, nonHDL-cholesterol, and WHR increased in all BMI categories.

Conclusions

PCOS is associated with cardiovascular risk. Lipid levels and BP increased in women of reproductive age with PCOS, regardless of BMI.

Systematic Review Registration

Open Science Framework (10.17605/OSF.IO/92NBY).

Lipid accumulation product (LAP) as a potential index to predict risk of insulin resistance in young, non-obese Asian Indian males from Southern India: observations from hyperinsulinemic-euglycemic clamp studies

INTRODUCTION

We aimed to compare the predictive accuracy of surrogate indices namely the lipid accumulation product (LAP) index, homeostatic model of assessment of insulin resistance (HOMA-IR), fasting glucose-insulin ratio (FG-IR) and the quantitative-insulin sensitivity check index (QUICKI), against the M value of hyperinsulinemic-euglycemic clamp (HEC), and to determine a cut-off value for the LAP index to predict risk of insulin resistance in non-obese (body mass index <21 kg/m²), normoglycemic, Asian Indian males from Southern India.

RESEARCH DESIGN AND METHODS

Data of HEC studies performed in 108 non-obese, normoglycemic, Asian Indian males was obtained retrospectively and the M value (a measure of whole-body insulin sensitivity) was calculated. The M value is the rate of whole-body glucose metabolism at the hyperinsulinemic plateau (a measure of insulin sensitivity) and is calculated between 60 and 120 min after the start of the insulin infusion in the HEC procedure. The LAP index, the HOMA-IR, FG-IR and QUICKI were calculated. Spearman's correlation and logistic regression analysis were performed. Cut-off value for the LAP index was obtained using receiver operating characteristics with area under curve (AUC) analysis at 95% CI. P value <0.05 was considered to be statistically significant.

RESULTS

Significant negative correlation was observed for the M value with LAP index (r=-0.39, p<0.001) while significant positive correlation was noted with FG-IR (r=0.25; p<0.01) and QUICKI (r=0.22; p<0.01). The LAP index cut-off value ≥33.4 showed 75% sensitivity and 75% specificity with AUC (0.72) to predict risk of insulin resistance in this cohort.

CONCLUSION

The LAP index showed higher predictive accuracy for the risk of insulin resistance as compared with HOMA-IR, QUICKI and FG-IR in non-obese, normoglycemic Asian Indian males from Southern India.

Prediction of Gut Microbial Community Structure and Function in Polycystic Ovary Syndrome With High Low-Density Lipoprotein Cholesterol

Gut microbiota has been proved to be involved in the occurrence and development of many diseases, such as type 2 diabetes, obesity, coronary heart disease, etcetera. It provides a new idea for the pathogenesis of polycystic ovary syndrome (PCOS). Our study showed that the gut microbial community of PCOS with high low-density lipoprotein cholesterol (LDLC) has a noticeable imbalance. Gut microbiota of PCOS patients was significantly changed compared with CON, and these changes were closely related to LDLC. Gut microbiota may affect the metabolic level of PCOS patients through multiple metabolic pathways, and lipid metabolism disorder may further aggravate the imbalance of gut microbiota. Actinomycetaceae, Enterobacteriaceae and Streptococcaceae had high accuracy in the diagnosis of PCOS and the differentiation of subgroups, suggesting that they may play an important role in the diagnosis and treatment of PCOS in the future. Also, the model we built showed good specificity and sensitivity for distinguishing PCOS from CON (including L_CON and L_PCOS, H_CON and H_PCOS). In conclusion, this is the first report on the gut microbiota of PCOS with high LDLC, suggesting that in the drug development or treatment of PCOS patients, the difference of gut microbiota in PCOS patients with different LDLC levels should be fully considered.

Lipid indices as simple and clinically useful surrogate markers for insulin resistance in the U.S. population

This study aimed to compare the accuracy of novel lipid indices, including the visceral adiposity index (VAI), lipid accumulation product (LAP), triglycerides and glucose (TyG) index, TyG-body mass index (TyG-BMI), and TyG-waist circumference (TyG-WC), in identifying insulin resistance and establish valid cutoff values. This cross-sectional study used the data of 11,378 adults, derived from the United States National Health and Nutrition Examination Survey (1999-2016). Insulin resistance was defined as a homeostasis model assessment-insulin resistance value above the 75th percentile for each sex and race/ethnicities. The area under the curves (AUCs) were as follows: VAI, 0.735; LAP, 0.796; TyG index, 0.723; TyG-BMI, 0.823, and; TyG-WC, 0.822. The AUCs for TyG-BMI and TyG-WC were significantly higher than those for VAI, LAP, and TyG index (vs. TyG-BMI, p < 0.001; vs. TyG-WC, p < 0.001). The cutoff values were as follows: VAI: men 1.65, women 1.65; LAP: men 42.5, women 42.5; TyG index: men 4.665, women 4.575; TyG-BMI: men 135.5, women 135.5; and TyG-WC: men 461.5, women 440.5. Given that lipid indices can be easily calculated with routine laboratory tests, these values may be useful markers for insulin resistance risk assessments in clinical settings.