Impact of 3-year changes in fasting insulin and insulin resistance indices on incident hypertension: Tehran lipid and glucose study

Additive interactions between obesity and insulin resistance on hypertension in a Chinese rural population

BACKGROUND

Adiposity and insulin resistance (IR) are closely associated with hypertension; however, the role of interactions between obesity phenotypes and IR in hypertension is unclear. This study aimed to evaluate the interactions of body mass index (BMI), waist circumference (WC), and body fat percentage (BF%) with IR on hypertension risk.

METHODS

We analyzed data from 4888 participants (mean age 57 years, 41.2% men) in the China Northwest Natural Population Cohort, Ningxia Project. BMI, WC, and BF% were determined using bioelectrical impedance analysis devices. IR was estimated using a homeostasis model assessment index (HOMA-IR). Multivariable-adjusted logistic regression was used to evaluate the association between HOMA-IR and hypertension risk. We calculated the relative excess risk and attributable proportion with their 95% confidence intervals (CIs) to assess whether adiposity phenotypes modified the effect of HOMA-IR on hypertension risk.

RESULTS

The crude prevalence of hypertension was 52.2%. The multivariable-adjusted odds ratio of HOMA-IR was 1.80 (95% CI: 1.23-2.65) for the risk of hypertension in the highest versus the lowest quartiles, but this association became marginal in models further adjusting for BMI, WC, and BF% (P for trend = 0.056). Relative excess risk and attributable proportion for interaction between high HOMA-IR and high BF% were 0.32 (0.04-0.59) and 0.33 (0.06-0.60), respectively. Additionally, high truncal and leg BF% and high HOMA-IR accounted for the hypertension risk in women, but not in men. We did not observe any significant interactions between BMI or WC and HOMA-IR on hypertension.

CONCLUSION

BF% modified the association between IR and increased risk of hypertension in women with high truncal and leg BF%, but not in men.

A nonlinear associations of metabolic score for insulin resistance index with incident diabetes: A retrospective Chinese cohort study

Background

The Metabolic score of insulin resistance (METS-IR) has recently been accepted as a reliable alternative to insulin resistance (IR), which was demonstrated to be consistent with the hyperinsulinemic-euglycemic clamp. Few pieces of research have focused on the relationship between METS-IR and diabetes in Chinese. The purpose of this research was to explore the effect of METS-IR on new-onset diabetes in a large multicenter Chinese study.

Methods

At the baseline of this retrospective longitudinal research, 116855 participators were included in the Chinese cohort study administered from 2010 to 2016. The subjects were stratified by quartiles of METS-IR. To assess the effect of METS-IR on incident diabetes, the Cox regression model was constructed in this study. Stratification analysis and interaction tests were applied to detect the potential effect of METS-IR and incident diabetes among multiple subgroups. To verify whether there was a dose-response relationship between METS-IR and diabetes, a smooth curve fitting was performed. In addition, to further determine the performance of METS -IR in predicting incident diabetes, the receiver operating characteristic curve (ROC) was conducted.

Results

The average age of the research participators was 44.08 ± 12.93 years, and 62868 (53.8%) were men. METS-IR were significant relationship with new-onset diabetes after adjusting for possible variables (Hazard ratio [HR]: 1.077; 95% confidence interval [CI]: 1.073-1.082, P < 0.0001), the onset risk for diabetes in Quartile 4 group was 6.261-fold higher than those in Quartile 1 group. Moreover, stratified analyses and interaction tests showed that interaction was detected in the subgroup of age, body mass index, systolic blood pressure, diastolic blood pressure, and fasting plasma glucose, there was no significant interaction between males and females. Furthermore, a dose-response correlation was detected between METS-IR and incident diabetes, the nonlinear relationship was revealed and the inflection point of METS-IR was calculated to be 44.43. When METS-IR≥44.43, compared with METS-IR < 44.43, the trend was gradually saturated, with log-likelihood ratio test P < 0.001. Additionally, the area under receiver operating characteristic of the METS-IR in predicting incident diabetes was 0.729, 0.718, and 0.720 at 3, 4, and 5 years, respectively.

Conclusions

METS-IR was correlated with incident diabetes significantly, and showed a nonlinear relationship. This study also found that METS-IR had good discrimination of diabetes.

Triglyceride-glucose index level and variability and outcomes in patients with acute coronary syndrome undergoing percutaneous coronary intervention: an observational cohort study

BACKGROUND

The associations between the long-term triglyceride-glucose (TyG) index level and variability and clinical outcomes in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI) have not been well studied.

METHODS

A total of 1,694 ACS patients with at least three postbaseline TyG index measurements within 2 years after PCI were included in the present study. The TyG index was defined as ln (fasting triglycerides [mg/dL] × fasting plasma glucose [mg/dL]/2). Multivariable-adjusted Cox proportional hazard models were used to examine the association between baseline and mean TyG index levels and TyG index variability and the risk of major adverse cardiovascular and cerebrovascular events (MACCEs).

RESULTS

During the median follow-up of 31 months, the overall incidence of MACCE was 5.9%. Both high baseline and mean TyG index levels were independently associated with an increased risk of MACCEs after adjustment for multiple potential confounders (hazard ratio [HR) 1.76 95% confidence interval [CI] 1.06-2.93; and HR 2.73 95% CI 1.57-4.74). Similarly, higher TyG index variability by successive variation (SD) was well related to a higher prevalence of MACCEs (HR 2.17 95% CI 1.28-3.68). In addition, the mean TyG index level showed a stronger risk prediction for MACCEs than the baseline TyG index level and TyG index-SD (AUCs 0.618 vs 0.566 vs 0.566).

CONCLUSIONS

The risk of MACCEs significantly increased with higher baseline and mean TyG index levels, as well as TyG index variability, in patients with ACS undergoing PCI. In particular, the mean TyG index level exhibited the highest predicting ability for MACCEs. Therefore, monitoring the long-term pattern of the TyG index deserves attention in clinical practice.

Distinct triglyceride-glucose trajectories are associated with different risks of incident cardiovascular disease in normal-weight adults

BACKGROUND

Long-term patterns of the triglyceride-glucose index (TyG index) and their effects on cardiovascular disease (CVD) among normal-weight adults are poorly characterized. This study aimed to identify TyG index trajectories in normal-weight adults and to determine their association with the risk of incident CVD.

METHODS

This study included 40,473 normal-weight participants who were free of stroke and myocardial infarction prior to or in 2012. The TyG index was calculated as ln (fasting triglyceride [mg/dL] × fasting glucose [mg/dL]/2), and the TyG index trajectories during 2006-2012 were identified by latent mixture modeling.

RESULTS

We identified five distinct TyG index trajectories according to TyG index range and changing pattern over time: low-stable (n = 9,806; mean TyG index 7.84-7.93), moderate-stable (n = 22,066; mean TyG index 8.43-8.52), high-decreasing (n = 1,469; mean TyG index 9.83-8.75), moderate-increasing (n = 5,842; mean TyG index 8.98-9.26), and high-stable (n = 1,290; mean TyG index 9.91-10.07). During 6.74 years of follow-up, we documented 1,577 incident CVD events. Compared with the low-stable pattern, the highest risk of CVD was observed in the high-stable pattern (hazard ratio [HR], 2.24; 95% confidence interval [CI]: 1.73-2.90), followed by the moderate-increasing pattern (HR, 1.70; 95% CI, 1.43-2.04), the high-decreasing pattern (HR, 1.45; 95% CI, 1.11-1.89), and the moderate-stable pattern (HR, 1.25; 95% CI, 1.08-1.44). Similar results were also observed for stroke and myocardial infarction.

CONCLUSIONS

Distinct TyG index trajectories were significantly associated differently subsequent risk of CVD in normal-weight individuals. These observations suggested that long-term trajectories of TyG index may be useful for predicting CVD among normal-weight adults.

Associations of the baseline level and change in glycosylated hemoglobin A1c with incident hypertension in non-diabetic individuals: a 3-year cohort study

BACKGROUND

Diabetes mellitus increases the risk of developing hypertension. The relationship between glycosylated hemoglobin A1c (HbA1c) level and incident hypertension remains controversial. This study examined the associations of the baseline level and change in the HbA1c level over 3 years with incident hypertension in non-diabetic individuals.

METHODS

This community-based cohort study was conducted with 2591 individuals aged 40-75 years without hypertension or diabetes at baseline, who participated in a longitudinal (REACTION) study program. Questionnaires were administered during interviews, and anthropometric and laboratory measurements were performed at baseline (2011) and follow-up (2014-2015). Multivariate logistic regression models were applied to estimate odds ratios (ORs) and 95% confidence intervals (CIs) of incident hypertension.

RESULTS

Over a median follow-up period of 3.08 years (interquartile range 3.00, 3.25), 384 (14.82%) subjects developed hypertension. In the fully adjusted linear regression models, change in HbA1c remained significantly associated with changes in systolic blood pressure and diastolic blood pressure [β-coefficient (95% CI), 4.421 (2.811-6.032), 1.681 (0.695-2.667)]. Logistic regression analyses showed that baseline HbA1c level was positively associated with incident hypertension in the unadjusted model; however, the association was no longer significant after further adjustment. Change in HbA1c was positively associated with the development of hypertension, both as a categorical variable stratified by tertiles [adjusted OR (95% CI) in the highest tertile was 1.690 (1.240-2.303) versus the lowest tertile)] and as a continuous variable [adjusted OR (95% CI), 1.242 (1.106-1.394)], independent of age, sex, body mass index, systolic blood pressure, fasting plasma glucose level, lipid profile, the HbA1c level at baseline and 3-year change in body mass index.

CONCLUSIONS

A higher baseline HbA1c level was not an independent risk factor for incident hypertension, whereas the change in HbA1c was independently associated with a greater longitudinal increase in blood pressure and an increased risk of incident hypertension in non-diabetic individuals.

Hyperinsulinemia negatively affects the association between insulin resistance and blood pressure

BACKGROUND AND AIMS

Although hyperinsulinemia and insulin resistance (IR) together cause metabolic diseases, the available evidence fails to link hyperinsulinemia with blood pressure (BP) elevation. To further understand the role of hyperinsulinemia in the pathophysiology of hypertension, we conducted this study to investigate the moderating effect of fasting insulin (FINS) on the association between IR and BP.

METHODS AND RESULTS

The health screening data of 72,076 individuals were analyzed for this moderation analysis. IR was indicated by the homeostatic model assessment of insulin resistance (HOMA-IR), triglyceride-glucose index (TyG), and triglyceride to high-density lipoprotein cholesterol ratio (TG/HDLc). In the adjusted model, three IR indicators were considered independent variables; FINS was used as a moderator, and systolic BP (SBP) and diastolic BP (DBP) were used as dependent variables. The regression coefficient of the interaction term between the three IR indicators and FINS was significantly negative in all moderation models. Simple slope tests and the Johnson-Neymann technique also indicated that FINS negatively moderated the association between IR and BP.

CONCLUSIONS

This moderation analysis showed that FINS negatively mediated the association between IR and BP, suggesting that hyperinsulinemia may buffer, not reinforce, the effect of IR on hypertension.

Agriophyllum Oligosaccharides Ameliorate Diabetic Insulin Resistance Through INS-R/IRS/Glut4-Mediated Insulin Pathway in db/db Mice and MIN6 Cells

We have previously reported that Agriophyllum oligosaccharides (AOS) significantly enhance glycemic control by increasing the activation of insulin receptor (INS-R), insulin receptor substrate-2 (IRS-2), phosphatidylinositol 3 kinase (PI3K), protein kinase B (AKT), peroxisome proliferator-activated receptor (PPAR)-γ, and glucose transporter 4 (Glut4) proteins in hepatic tissues. However, the effect of glucose control by AOS on the regulation of pancreatic tissues in db/db mice and MIN6 cells remains to be determined. An oral dose of AOS (380 or 750 mg/kg) was administered to type-2 diabetic db/db mice for 8 weeks to determine whether AOS regulates glucose by the INS-R/IRS/Glut4-mediated insulin pathway. Meanwhile, the effects of AOS on glucose uptake and its related signaling pathway in MIN6 cells were also investigated. The results showed that the random blood glucose (RBG) level in the AOS-treated group was lower than that in the control group. AOS reduced the levels of glycated hemoglobin (HbA1c) and free fatty acid (FFA) and significantly improved the pathological changes in the pancreatic tissues in db/db mice. Moreover, immunohistochemical analysis revealed that the expression of INS-R, IRS-1, IRS-2, and Glut4 was increased in the AOS-treated group than in the model group. Further, in vitro experiments using MIN6 cells showed that AOS regulated INS-R, IRS-1, IRS-2, and Glut4 protein and mRNA levels and attenuated insulin resistance and cell apoptosis. The results of both in vitro and in vivo experiments were comparable. Ultra-performance liquid chromatography coupled with time-of-flight mass spectrometric analysis of AOS with precolumn derivatization with 3-amino-9-ethylcarbazole (AEC) tentatively identified five types of sugars: glucose, lactose, rutinose, glucuronic acid, and maltotriose. Our present study clearly showed that AOS is efficacious in preventing hyperglycemia, possibly by increasing insulin sensitivity and improving IR by regulating the INS-R/IRS/Glut4 insulin signal pathway. Therefore, AOS may be considered as a potential drug for diabetes treatment.

Association of metabolic score for insulin resistance and its 6-year change with incident type 2 diabetes mellitus

BACKGROUND

The evidence for the association between metabolic score for insulin resistance (METS-IR) and type 2 diabetes mellitus (T2DM) is limited. We aimed to explore the association of METS-IR and its 6-year change with risk of incident T2DM in a rural Chinese population.

METHODS

We analyzed data for 12 107 participants (mean age 50.48 years). A Cox proportional-hazard model was used to estimate the association of METS-IR with incident T2DM by using hazard ratios (HRs) and 95% confidence intervals (CIs); a logistic regression model was used to assess the association of 6-year METS-IR change with incident T2DM by using odds ratios (ORs) and 95% CIs. We used subgroup analyses of the association of METS-IR and its 6-year change with incident T2DM by sex, age, and baseline fasting plasma glucose (FPG) level as well as restricted cubic splines to describe the dose-response association.

RESULTS

The association of METS-IR and 6-year METS-IR change with incident T2DM was significant (per SD unit increase: HR = 1.80, 95% CI: 1.60-2.02 for METS-IR, OR = 1.42, 95% CI: 1.28-1.57 and OR = 1.59, 95% CI: 1.44-1.76 for relative and absolute METS-IR change). The significant association remained on subgroup analyses by sex, age, and baseline FPG level. Dose-response analysis demonstrated that the probability of incident T2DM was significantly increased with increasing METS-IR and 6-year METS-IR change.

CONCLUSIONS

Increased METS-IR and 6-year METS-IR change were positively associated with risk of incident T2DM in a rural Chinese population. METS-IR may be a vital indicator for identifying T2DM.

Change in triglyceride-glucose index predicts the risk of cardiovascular disease in the general population: a prospective cohort study

BACKGROUND

Previous studies has shown a significant relationship between baseline triglyceride-glucose (TyG) index and subsequent cardiovascular disease (CVD). However, the effect of longitudinal changes in TyG index on the risk of CVD remains uncertain. This study aimed to investigate the association between change in TyG index and the risk of CVD in the general population.

METHODS

The current study included 62,443 Chinese population who were free of CVD. The TyG index was calculated as ln [fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2], and change in TyG index was defined as the difference between the TyG index in 2010 and that in 2006. Multivariable-adjusted Cox proportional hazard models and restricted cubic spline analysis were used to examine the association between change in TyG index and the risk of CVD.

RESULTS

During a median follow-up of 7.01 years, 2530 (4.05%) incident CVD occurred, including 2018 (3.23%) incident stroke and 545 (0.87%) incident myocardial infarction (MI). The risk of developing CVD increased with the quartile of change in TyG index, after adjustment for multiple potential confounders, the hazard ratios for the Q4 group versus the Q1 group were 1.37 (95% confidence interval [CI], 1.21-1.54) for the overall CVD, 1.38 (95% CI, 1.19-1.60) for stroke, and 1.36 (95% CI, 1.05-1.76) for MI. Restricted cubic spline analysis also showed a cumulative increase in the risk of CVD with increases in the magnitude of change in TyG index. The addition of change in TyG index to a baseline risk model for CVD improved the C-statistics (P = 0.0097), integrated discrimination improvement value (P < 0.0001), and category-free net reclassification improvement value (P < 0.0001). Similar results were observed for stroke and MI.

CONCLUSIONS

Substantial changes in TyG index independently predict the risk of CVD in the general population. Monitoring long-term changes in TyG may assist with in the early identification of individuals at high risk of CVD.