Impact of serum triglyceride and high density lipoprotein cholesterol levels on early-phase insulin secretion in normoglycemic and prediabetic subjects

Elevated triglyceride/high-density lipoprotein-cholesterol ratio as a risk factor for progression to prediabetes: a 5-year retrospective cohort study in Japan

Purpose

The triglyceride-to-high-density lipoprotein-cholesterol (TG/HDL-C) ratio is considered an alternative marker for insulin resistance. This longitudinal retrospective study investigated the relationship between TG/HDL-C ratio and the risk of progression to prediabetes.

Methods

We investigated 24,604 Japanese participants (14,609 men and 9,995 women) who underwent annual medical health checkups in 2017 (baseline) and 2022. All participants had no diabetes and prediabetes at baseline. No lipid-lowering medications were taken during the follow-up period. Participants were divided into four groups according to the quartiles of TG/HDL-C ratio at baseline. Multivariable-adjusted Cox regression analysis was conducted to examine hazard ratios (HRs) of progression to prediabetes. Receiver operating characteristic curves were used to determine the optimal cutoff value of TG/HDL-C ratio for prediction of prediabetes.

Results

Compared with the lowest TG/HDL-C ratio quartile (Q1) group, the adjusted HRs (95% confidence intervals (CI)) of progression to prediabetes in the Q2, Q3, and Q4 groups, respectively, were 1.17 (0.92-1.47), 1.26 (1.01-1.56), and 1.77 (1.41-2.23) for men and 1.07 (0.60-1.11), 1.19 (1.08-1.29), and 1.58 (1.18-2.31) for women. For every 1 unit increase in TG/HDL-C ratio, the adjusted HRs (95% CI) for progression to prediabetes was 1.09 (1.04-1.13) in men and 1.10 (1.04-1.15) in women. The optimal TG/HDL-C ratio cutoffs were 1.71 and 0.97 in men and women, respectively, but the area under the curve was > 0.70 in both sexes.

Conclusion

High TG/HDL-C ratio is a risk factor for progression to prediabetes in Japanese men and women, but it had low discriminative ability in predicting prediabetes risk.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-023-01329-8.

Interaction between the GCKR rs1260326 variant and serum HDL cholesterol contributes to HOMA-β and ISIMatusda in the middle-aged T2D individuals

This study aims to investigate the correlations between islet function/ insulin resistance and serum lipid levels, as well as to assess whether the strength of such correlations is affected by the GCKR rs1260326 variant in healthy and T2D individuals. We performed an oral glucose tolerance test (OGTT) on 4889 middle-aged adults, including 3135 healthy and 1754 T2D individuals from the REACTION population study in the Nanjing region. We also measured their serum lipid levels and genotyped for rs1260326. We found that serum high-density lipoprotein (HDL) cholesterol and triglyceride (TG) levels were independently correlated with indexes of islet function (HOMA-β and IGI [insulinogenic index]) and insulin resistance (HOMO-IR and ISIMatsuda) in both healthy and T2D individuals. The correlations were significantly decreased in T2D individuals, with significant heterogeneities compared to healthy controls (I2 > 75%, Phet < 0.05). Although no correlation was observed between serum total cholesterol (TC) level and islet function/ insulin resistance in healthy controls, significant correlations were found in T2D individuals, with significant heterogeneity to healthy controls in the correlation with ISIMatsuda(I2 = 85.3%, Phet = 0.009). Furthermore, we found significant interactions of the GCKR rs1260326 variant for the correlations between serum HDL cholesterol and HOMA-β/ISIMatsuda in T2D subjects (P = 0.015 and 0.038, respectively). These findings illustrate that distinct correlations between serum lipid levels and islet function/ insulin resistance occurred in T2D subjects compared to healthy individuals. Common gene variants, such as rs1260326, might interact substantially when studied in specific populations, especially T2D disease status.

The protective effects of lipoxin A4 on type 2 diabetes mellitus: A Chinese prospective cohort study

BACKGROUND

Several cellular and animal studies have suggested that lipoxin A4 (LXA4) has a protective effect on type 2 diabetes mellitus (T2DM) development. However, little is known about whether LXA4 influences T2DM development at the population level.

METHODS

We included 2755 non-diabetic participants from a cohort study in China who were followed for about seven years. Cox proportional hazards model was used to estimate hazard ratios (HRs) and 95% confidence intervals (CI) for the association between LXA4 and incident T2DM. Mediation models were used to examine how serum lipids as mediators impact the association between LXA4 and T2DM.

RESULTS

In total, 172 newly diagnosed T2DM cases were identified. Multivariate-adjusted HR for T2DM in the fourth compared with the first quartile of LXA4 was 0.62 (95% CI: 0.40-0.96). When used the optimal cutoff value determined by the receiver operating characteristic curve, the results showed participants with LXA4 > 2.84 ng/mL had a decreased T2DM risk compared to those with LXA4 ≤ 2.84 ng/mL (HR: 0.63, 95% CI: 0.45-0.89). The effect of LXA4 on incident T2DM was significantly modified by gender (P _-interaction = 0.024) and family history of diabetes (P _-interaction = 0.025). Additionally, the association between LXA4 and incident T2DM was partially suppressed by the TyG and TG/HDL-c ratio, with a suppression proportion of 22.2% and 16.0%, respectively.

CONCLUSIONS

Higher LXA4 levels are significantly associated with a lower risk of T2DM development. The present findings would be helpful in understanding the effect of LXA4 on T2DM development at the population level.

Association of TG/HDLC ratio trajectory and risk of type 2 diabetes: A retrospective cohort study in China

BACKGROUND

The association of ratio of triglycerides to high-density lipoprotein cholesterol (TG/HDL-C ratio) change trajectory with risk of type 2 diabetes mellitus (T2DM) remains unknown. The aim of this study was to evaluate the association between risk of T2DM and TG/HDL-C ratio change trajectory.

METHODS

A total of 18 444 participants aged 18-80 years old were included in this cohort study. Linear regression and quadratic regression models were used to determine the TG/HDL-C ratio change trajectory. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between TG/HDL-C ratio change trajectory and probability of T2DM.

RESULTS

T2DM developed in 714 participants during a median follow-up of 5.74 years (92 076.23 person-years of follow-up). After adjusting for baseline potential confounders, odds of T2DM were greater for participants with the increasing, U-shape, bell-shape, and other shape change vs decreasing change (adjusted OR [aOR] 2.01, 95% CI 1.42-2.81; 1.56, 1.15-2.13; 1.60, 1.17-2.20; and 1.49, 1.13-2.00, respectively). The results were robust in the sensitivity analyses on excluding baseline participants with T2DM. Moreover, the associations remained significant with male sex, age <60 years and body mass index <24 kg/m2 .

CONCLUSIONS

This retrospective study revealed increased probability of T2DM with increasing, U-shape, bell-shape, and other-shape TG/HDL-C ratio change trajectories, especially with male sex, age <60 years and body mass index <24 kg/m2 .

Comparison of Serum PCSK9 Levels in Subjects with Normoglycemia, Impaired Fasting Glucose, and Impaired Glucose Tolerance

We investigated proprotein convertase subtilisin/kexin type 9 (PCSK9) concentrations in individuals with normoglycemia, impaired fasting glucose (IFG), and impaired glucose tolerance (IGT). This was a pilot, cross-sectional study including 92 individuals who had not been diagnosed with or treated for diabetes. We measured PCSK9 levels in three groups of subjects; namely, normoglycemia (n=57), IFG (n=21), and IGT (n=14). Individuals with IFG and IGT showed higher PCSK9 concentrations than those in the normoglycemic group, with the highest serum PCSK9 concentrations found in individuals with IGT (55.25±15.29 ng/mL for normoglycemia, 63.47±17.78 ng/mL for IFG, 72.22±15.46 ng/mL for IGT, analysis of variance P=0.001). There were no significant differences in high- or low-density lipoprotein cholesterol among groups. Serum PCSK9 levels are increased in patients with prediabetes compared to subjects with normoglycemia.

Triglycerides/high-density lipoprotein cholesterol is a predictor similar to the triglyceride-glucose index for the diagnosis of metabolic syndrome using International Diabetes Federation criteria of insulin resistance in obese adolescents: a cross-sectional study

Objectives Metabolic syndrome (MS) is a fatal endocrinopathy that begins with insulin resistance (IR) and causes abdominal obesity, glucose intolerance, or systemic disorders. This study was aimed to determine the cut-off values for the triglyceride (TG)/high-density lipoprotein cholesterol (TG/HDL-C) ratio, the TG glucose (TyG) index and homeostasis model assessment (HOMA-IR) for the diagnosis of MS in obese adolescents, and to compare which of the three indexes would offer a more accurate approach to diagnosis. Methods The study population comprised 1,171 obese adolescents (639 females and 532 males aged 10-16 years, Body Mass Index (BMI)>=95th percentile). Indirect measures of IR screening for MS were the TG/HDL ratio, TyG index, and HOMA-IR. The cut-off values of the TG/HDL ratio, TyG index, and HOMA-IR were obtained from receiver operation characteristic (ROC) curves. Results HOMA-IR had a significant positive correlation with the TyG index (r=0.352, p<0.001) and TG/HDL-C (r=0.291, p<.001). The TyG index and TG/HDL-C showed a strong positive correlation (r=0.901, p<0.001). The TG/HDL-C ratio showed a larger ROC Area under Curve (AUC=0.849) than HOMA-IR index (AUC=0.689), but as a predictor similar to TyG index (AUC=0.833) when screening for MS. The cut-off values for MS were as follows: TG/HDL-C ratio>2.16 (sensitivity: 88.8%; specificity: 49.7%), TyG index>8.50 (sensitivity: 85.6%; specificity: 57.0%) and HOMA-IR>2.52 (sensitivity: 83.2%; specificity: 40.4%). Conclusions Both the TyG index and TG/HDL-C ratio are better markers than HOMA-IR to determine the risk of metabolic syndrome according to IDF criteria. Besides, the TyG index and TG/HDL-C ratio have similar differentiating powers to determine this risk in obese Turkish adolescents.

Comparative analysis of the efficacy of omega-3 fatty acids for hypertriglyceridaemia management in Korea

WHAT IS KNOWN AND OBJECTIVE

This study aimed to compare the ability of statin monotherapy (ST group), omega-3 fatty acid monotherapy (OM_A group) and combination therapy with omega-3 fatty acids and a statin (OM_S group), to reduce triglyceride (TG) levels in patients with hypertriglyceridaemia.

METHODS

In this retrospective cohort study, we extracted data from the electronic medical records of patients initially prescribed either a statin or omega-3 fatty acids between January, 2009 and December, 2013. We performed a comparative analysis of the change in cholesterol levels between baseline and an average of 3 months later.

RESULTS AND DISCUSSION

Data were extracted for 2071 patients. The average daily eicosapentaenoic acid (EPA) ethyl ester and docosahexaenoic acid (DHA) ethyl ester intake was 1689 mg, and 79-86% of the OM_A and OM_S groups were prescribed two omega-3 fatty acid capsules. At a baseline TG level of between 200 and 500 mg/dL, TG levels were reduced by 16 ± 2·8% in the ST group, 28 ± 2·8% in the OM_A group and 29 ± 2·3% in the OM_S group (P = 0·001 for ST group vs. OM_A and OM_S groups), with no difference between the OM_A and OM_S groups. At a baseline TG level ≥500 mg/dL, there was no difference in TG level reduction between the three groups (54 ± 7·3%, 55·8 ± 3·5% and 51·8 ± 6·8%, respectively, P = 0·851).

WHAT IS NEW AND CONCLUSION

Although omega-3 fatty acids are not considered the primary medication for hypertriglyceridaemia, the prescription of omega-3 fatty acids is justifiable if reduction in TG levels is judged to be necessary.

Relationship between insulin sensitivity and insulin secretion rate: not necessarily hyperbolic

AIMS

There is general acceptance that the physiological relationship between insulin sensitivity and insulin secretion is hyperbolic. This conclusion has evolved from studies in which one test assessed both variables, and changes in plasma insulin concentration were used as a surrogate measure for insulin secretion rate. The aim of this study was to see if a hyperbolic relationship would also emerge when separate and direct measures were used to quantify both insulin sensitivity and insulin secretion rate.

METHODS

Steady-state plasma glucose (SSPG) was determined in 146 individuals without diabetes using the insulin suppression test, with 1/SSPG used to quantify insulin sensitivity. The graded-glucose infusion test was used to quantify insulin secretion rate. Plasma glucose and insulin concentrations obtained during an oral glucose tolerance test (OGTT) were used to calculate surrogate estimates of insulin action and insulin secretion rate. A hyperbolic relationship was assumed if the β coefficient was near -1 using the following model: log (insulin secretion measure) = constant + β × log (insulin sensitivity measure).

RESULTS

OGTT calculations of insulin sensitivity (Matsuda) and plasma insulin response [ratio of insulin/glucose area-under-the-curve (AUC) or insulin total AUC] provided the expected hyperbolic relationship [β = -0.95, 95% CI (-1.09, -0.82); -1.06 (-1.14, -0.98)]. Direct measurements of insulin sensitivity and insulin secretion rate did not yield the same curvilinear relationship [β = -1.97 (-3.19, -1.36)].

CONCLUSIONS

These findings demonstrate that the physiological relationship between insulin sensitivity and insulin secretion rate is not necessarily hyperbolic, but will vary with the method(s) by which it is determined.

The triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio as a predictor of insulin resistance but not of β cell function in a Chinese population with different glucose tolerance status

Background

Triglyceride/high-density lipoprotein-cholesterol (TG/HDL-C) ratio was a surrogate marker of IR; however, the relationship of TG/HDL-C with IR might vary by ethnicity. This study aims to investigate whether lipid ratios-TG/HDL-C, cholesterol/high-density lipoprotein-cholesterol (TC/HDL-C) ratio, low-density lipoprotein-cholesterol/high-density lipoprotein-cholesterol (LDL-C/HDL-C)) could be potential clinical markers of insulin resistance (IR) and β cell function and further to explore the optimal cut-offs in a Chinese population with different levels of glucose tolerance.

Methods

Four hundred seventy-nine subjects without a history of diabetes underwent a 75 g 2 h Oral Glucose Tolerance Test (OGTT). New-onset diabetes (n = 101), pre-diabetes (n = 186), and normal glucose tolerance (n = 192) were screened. IR was defined by HOMA-IR > 2.69. Based on indices (HOMA-β, early-phase disposition index [DI₃₀], (ΔIns30/ΔGlu30)/HOMA-IR and total-phase index [DI₁₂₀]) that indicated different phases of insulin secretion, the subjects were divided into two groups, and the lower group was defined as having inadequate β cell compensation. Logistic regression models and accurate estimates of the areas under receiver operating characteristic curves (AUROC) were obtained.

Results

In all of the subjects, TG/HDL, TC/HDL-C, LDL-C/HDL-C, and TG were significantly associated with IR. The AUROCs of TG/HDL-C and TG were 0.71 (95 % CI: 0.66–0.75) and 0.71 (95 % CI: 0.65–0.75), respectively. The optimal cut-offs of TG/HDL-C and TG for IR diagnosis were 1.11 and 1.33 mmol/L, respectively. The AUROCs of TC/HDL-C and LDL-C/HDL-C were 0.66 and 0.65, respectively, but they were not acceptable for IR diagnosis. TG/HDL-C,LDL-C/HDL-C and TG were significantly associated with HOMA-β, but AUROCs were less than 0.50; therefore, the lipid ratios could not be predictors of basal β cell dysfunction. None of the lipid ratios was associated with early-phase insulin secretion. Only TG/HDL-C and TG were significantly correlated with total-phase insulin secretion, but they also were not acceptable predictors of total-phase insulin secretion (0.60 < AUROC < 0.70).

Conclusions

In a Chinese population with different levels of glucose tolerance, TG/HDL-C and TG could be the predictors of IR. The lipid ratios could not be reliable makers of β cell function in the population.

Interactive effects of C-reactive protein levels on the association between APOE variants and triglyceride levels in a Taiwanese population

Background

Apolipoprotein E (APOE) plays a major role in lipid metabolism and inflammation. However, the association between APOE gene polymorphisms and serum triglyceride levels remains controversial. We tested the effects of APOE variants on triglyceride levels and their interactions with the inflammatory marker C-reactive protein (CRP) in a Taiwanese population.

Methods

Two APOE single nucleotide polymorphisms (SNPs) rs429358 and rs7412 were genotyped by TaqMan Assay using real time PCR in 595 healthy subjects attending the clinic for routine visits.

Results

After adjustment for clinical covariates, subjects carrying the rs429358-TT genotype and non-ε4 alleles were found to have higher CRP levels, whereas those with rs7412-CC genotype and non-ε2 alleles had significantly higher total and low-density lipoprotein cholesterol levels (all P < 0.01). Using subgroup and interaction analyses, we observed significantly lower triglyceride levels in subjects carrying the rs429358-TT genotype and non-ε4 alleles in the low CRP group (P = 2.71× 10⁻⁴ and P = 4.32 × 10⁻⁴, respectively), but not in those in the high CRP group (interaction P = 0.013 and 0.045, respectively). In addition, multivariate stepwise linear regression analysis showed that subjects carrying the rs429358-TT genotype and non-ε4 alleles with low CRP levels had significantly lower triglyceride levels (P < 0.001 and P < 0.001, respectively). In addition, when combined with the risk alleles of GCKR, APOA5 and LPL gene variants, we observed that triglyceride levels increased significantly with the number of risk alleles (P = 2.9 × 10⁻¹²).

Conclusions

The combination of SNPs and ε alleles at the APOE locus is involved in managing lipid and CRP levels in the Taiwanese population. APOE polymorphisms interact with CRP to regulate triglyceride levels, thus triglyceride concentration is influenced by both the genetic background of the APOE locus and the inflammatory status of a subject.

Electronic supplementary material

The online version of this article (doi:10.1186/s12944-016-0262-z) contains supplementary material, which is available to authorized users.

TyG Index Change Is More Determinant for Forecasting Type 2 Diabetes Onset Than Weight Gain

The risk of type 2 diabetes associated with obesity appears to be influenced by other metabolic abnormalities, and there is controversy about the harmless condition of the metabolically healthy obese (MHO) state. The aim of this study is to assess the risk of diabetes and the impact of changes in weight and in triglyceride-glucose index (TyG index), according to the metabolic health and obesity states.We analyzed prospective data of the Vascular Metabolic CUN cohort, a population-based study among a White European population (mean follow-up, 8.9 years). Incident diabetes was assessed in 1923 women and 3016 men with a mean age at baseline of 55.33 ± 13.68 and 53.78 ± 12.98 years old.A Cox proportional-hazard analysis was conducted to estimate the hazard ratio (HR) of diabetes on metabolically healthy nonobese (MHNO), metabolically healthy obese, metabolically unhealthy nonobese (MUNO), and metabolically unhealthy obese (MUO). A continuous standardized variable (z-score) was derived to compute the HR for diabetes per 1-SD increment in the body mass index (BMI) and the TyG index.MHO, MUNO, and MUO status were associated with the development of diabetes, HR of 2.26 (95% CI: 1.25-4.07), 3.04 (95% CI: 1.69-5.47), and 4.04 (95% CI: 2.14-7.63), respectively. MUNO individuals had 1.82 greater risk of diabetes compared to MHO subjects (95% CI: 1.04-3.22). The HRs for incident diabetes per 1-SD increment in BMI and TyG indexes were 1.23 (95% CI: 1.04-1.44) and 1.54 (95% CI: 1.40-1.68). The increase in BMI did not raise the risk of developing diabetes among metabolically unhealthy subjects, whereas increasing the TyG index significantly affect the risk in all metabolic health categories.Metabolic health is more important determinant for diabetes onset than weight gain. The increase in weight does not raise the risk of developing diabetes among metabolically unhealthy subjects.

The TyG index may predict the development of cardiovascular events

BACKGROUND

Cardiovascular disease (CVD) is the worldwide leading cause of morbidity and mortality. An early risk detection of apparently healthy people before CVD onset has clinical relevance in the prevention of cardiovascular events. We evaluated the association between the product of fasting plasma glucose and triglycerides (TyG index) and CVD.

MATERIAL AND METHODS

A total of 5014 patients of the Vascular Metabolic CUN cohort (VMCUN cohort) were followed up during a median period of 10 years. We used a Cox proportional-hazard ratio with repeated measures to estimate the risk of incidence of CVD across quintiles of the TyG index, calculated as ln[fasting triglycerides (mg/dL) × fasting plasma glucose (mg(dL)/2], and plotted a receiver-operating characteristics (ROC) curve to compare a prediction model fitted on the variables used in the Framingham risk score, a new model containing the Framingham variables with the TyG index, and the risk of coronary heart disease.

RESULTS

A higher level of TyG index was significantly associated with an increased risk of developing CVD independent of confounding factors with a value of 2·32 (95% CI: 1·65-3·26) for those in the highest quintile and 1·52 (95% CI: 1·07-2·16) for those in the fourth quintile. The areas under the curve (AUC) of the ROC plots were 0·708 (0·68-0·73) for the Framingham model and 0·719 (0·70-0·74) for the Framingham + TyG index model (P = 0·014).

CONCLUSIONS

The TyG index, a simple measure reflecting insulin resistance, might be useful to early identify individuals at a high risk of developing a cardiovascular event.