Association of HDL-C and apolipoprotein A-I with the risk of type 2 diabetes in subjects with impaired fasting glucose

Association between high-density lipoprotein cholesterol and type 2 diabetes mellitus: dual evidence from NHANES database and Mendelian randomization analysis

Background

Low levels of high-density lipoprotein cholesterol (HDL-C) are commonly seen in patients with type 2 diabetes mellitus (T2DM). However, it is unclear whether there is an independent or causal link between HDL-C levels and T2DM. This study aims to address this gap by using the The National Health and Nutrition Examination Survey (NHANES) database and Mendelian randomization (MR) analysis.

Materials and methods

Data from the NHANES survey (2007-2018) with 9,420 participants were analyzed using specialized software. Logistic regression models and restricted cubic splines (RCS) were used to assess the relationship between HDL-C and T2DM incidence, while considering covariates. Genetic variants associated with HDL-C and T2DM were obtained from genome-wide association studies (GWAS), and Mendelian randomization (MR) was used to evaluate the causal relationship between HDL-C and T2DM. Various tests were conducted to assess pleiotropy and outliers.

Results

In the NHANES study, all groups, except the lowest quartile (Q1: 0.28-1.09 mmol/L], showed a significant association between HDL-C levels and reduced T2DM risk (all P < 0.001). After adjusting for covariates, the Q2 [odds ratio (OR) = 0.67, 95% confidence interval (CI): (0.57, 0.79)], Q3 [OR = 0.51, 95% CI: (0.40, 0.65)], and Q4 [OR = 0.29, 95% CI: (0.23, 0.36)] groups exhibited average reductions in T2DM risk of 23%, 49%, and 71%, respectively. In the sensitivity analysis incorporating other lipid levels, the Q4 group still demonstrates a 57% reduction in the risk of T2DM. The impact of HDL-C levels on T2DM varied with age (P for interaction = 0.006). RCS analysis showed a nonlinear decreasing trend in T2DM risk with increasing HDL-C levels (P = 0.003). In the MR analysis, HDL-C levels were also associated with reduced T2DM risk (OR = 0.69, 95% CI = 0.52-0.82; P = 1.41 × 10-13), and there was no evidence of pleiotropy or outliers.

Conclusion

This study provides evidence supporting a causal relationship between higher HDL-C levels and reduced T2DM risk. Further research is needed to explore interventions targeting HDL-C levels for reducing T2DM risk.

Association between serum lipid profile during the first and second trimester of pregnancy as well as their dynamic changes and gestational diabetes mellitus in twin pregnancies: a retrospective cohort study

BACKGROUND

Abnormal lipid metabolism is associated with gestational diabetes mellitus (GDM) in singleton pregnancies. Data were lacking on twin pregnancies with GDM. We explored the association between serum lipid profiles in the first and second trimesters as well as their dynamic changes and GDM in twin pregnancies.

METHODS

This was a retrospective cohort study of 2739 twin pregnancies that underwent a 75-g oral glucose tolerance test (OGTT) and were selected from the Beijing Birth Cohort Study from June 2013 to May 2021. Cholesterol (CHO), triglyceride (TG), high-density lipoprotein (HDL) and low-density lipoprotein (LDL) levels were measured at mean 9 and 25 weeks of gestation. We described maternal lipid levels in different tertiles that were associated with the risk of GDM stratified for age, pre-BMI, and fertilization type. GDM patients were divided into two groups according to OGTT: elevated fasting plasma glucose only (FPG group) and the rest of the GDM (non-FPG group). We estimated the relative risk of GDM with multivariable logistic regression models.

RESULTS

In this study, we found that 599 (21.9%, 599/2739) twin pregnancies developed GDM. They had increased CHO, TG, LDL, and LDL/HDL, decreased HDL levels in the first trimester, and increased TG as well as decreased HDL in the second trimester in univariate analyses, each P < 0.05. In multivariate analysis, when TG > 1.67 mmol/l (upper tertile) in elderly individuals, nonoverweight and ART groups increased the risk of GDM by 2.7-fold, 2.3-fold and 2.2-fold, respectively, compared with TG < 0.96 mmol/l (lower tertile). This effect remained in the abovementioned groups in the second trimester. Moreover, high TGs increased the risk of GDM in the FPG group (OR = 2.076, 95% CI 1.130-3.815) and non-FPG group (OR = 2.526, 95% CI 1.739-3.67) in the first trimester when TG > 1.67 mmol/l, and the rising risk in the non-FPG group as the TG tertile increased remained in the second trimester. HDL predominantly showed a negative association with elevated FPG in the second trimester (p < 0.05).

CONCLUSIONS

Twin pregnancies with GDM have higher lipid levels. Increased TGs in the first and second trimesters are strongly associated with GDM, especially in elderly individuals, nonoverweight and ART groups. Lipid profiles varied among different GDM subtypes.

Associations of apolipoproteinA1, high density lipoprotein cholesterol with hemoglobin glycation index and triglyceride-glucose index in Chinese adults with coronary artery disease

AIMS

Scarce data explored the associations of apolipoproteins with hemoglobin glycation index (HGI) and triglyceride-glucose (TyG) index. This study determined associations of serum apolipoproteinA1 (ApoA1) and high density lipoprotein cholesterol (HDL-C) with HGI and TyG index in coronary artery disease (CAD) patients.

METHODS

A total of 10,803 CAD patients were included in this cross-sectional pilot study. Serum concentrations of ApoA1 and HDL-C were measured. Analyses of covariance were used to compare the mean differences in glucose metabolism indices (e.g., HGI, TyG index, hemoglobin glycation [HbA1c], fasting blood glucose [FBG]) among the quartiles of ApoA1, HDL-C and HDL-C/ApoA1 ratio.

RESULTS

In multivariate analysis, higher ApoA1, HDL-C and HDL-C/ApoA1 ratio were associated with significantly lower HGI (Quartile [Q]4 vs. Q1: -0.032 % vs. 0.017 % for ApoA1; -0.072 % vs. 0.079 % for HDL-C; -0.083 % vs. 0.085 % for HDL-C/ApoA1 ratio). Intermediate ApoA1 level was inversely associated with TyG index (Q2 vs. Q1: 296.278 vs. 306.794). The mean TyG index were significantly decreased with increased HDL-C and HDL-C/ApoA1 ratio (Q4 vs. Q1: 298.584 vs. 309.221 for HDL-C; 300.405 vs. 315.218 for HDL-C/ApoA1 ratio). Moreover, the inverse associations of ApoA1, HDL-C and HDL-C/ApoA1 ratio with HbA1c and FBG also were observed. In path analysis, the associations of HDL-C and HDL-C/ApoA1 ratio with TyG index were mediated by obesity.

CONCLUSION

This study provided further support for the hypoglycemic effects of ApoA1 and HDL-C in patients with CAD. Replication of these findings is warranted in further longitudinal studies in different populations.

Association between high-density lipoprotein cholesterol to apolipoprotein A ratio and diabetic retinopathy: A cross-sectional study

AIMS

Our study is aimed to investigate the relationship between high-density lipoprotein cholesterol to apolipoprotein A ratio (HDL-C/ApoA) and diabetic retinopathy (DR) in subjects with type 2 diabetes mellitus (T2DM).

METHODS

We retrospect the consecutive medical files of 1058 subjects with T2DM and recorded their clinical information and laboratory findings. Subjects with T2DM were divided into DR group (n = 522) and non-DR group (n = 536). We compared the lipids values of the two groups. Meanwhile we also observed the prevalence of DR at different HDL-C/ApoA levels. Binary logistic regression was used to correct confounding factors. Smooth curve fitting model and subgroup analysis were used to determine the correlation, non-linear relationship and threshold effect between HDL/ApoA and DR.

RESULTS

HDL-C/ApoA value of DR group was significantly higher than non-DR group (0.88 ± 0.17 vs 0.84 ± 0.13, P < 0.05). The prevalence of DR significantly increased as HDL-C/ApoA level increased. There was association between HDL/ApoA levels and DR in the adjusted models (OR 1.55, 95%CI 0.60 to 4.02). After full adjustments for other relevant clinical covariates, patients with HDL/ApoA values in quartile 3 (Q3) had 1.50 times (95 % CI 1.00 to 2.17) and in Q4 had 2.39 times (95%CI 1.65 to 3.47) as high as the risk of DR compared with patients in Q1. HDL/ApoA showed a non-linear relationship with DR, with an inflection point value of 0.759. When HDL/ApoA>0.759, HDL/ApoA was significantly positively associated with DR (HR = 26.508, 95 % CI 7.623-92.174; P < 0.0001). Compared to patients with age < 60, HDL/ApoA was obviously associated with DR when age ≥ 60 (OR = 38.05, 95 % CI 8.06-179.69; P < 0.001).

CONCLUSIONS

HDL-C/ApoA was found to be associated with the incidence of DR in patients with T2DM. After adjusting potential related factors HDL-C/ApoA OR value was 1.55 (95%CI 0.60 to 4.02). A non-linear association between HDL/ApoA and DR was observed in T2DM. Subgroup analysis showed that age could alter the relationship between HDL/ApoA and DR.

The relationship between the ratio of gamma-glutamyltransferase to high-density lipoprotein cholesterol and the risk of diabetes mellitus using publicly available data: a secondary analysis based on a longitudinal study in Japan

BACKGROUND

The ratio of gamma-glutamyltransferase to high-density lipoprotein cholesterol (GGT/HDL-C) has been highlighted in nonalcoholic fatty liver disease (NAFLD) by previous studies. However, there have been fewer investigations into the correlation between the GGT/HDL-C ratio and type 2 diabetes mellitus (T2DM) incidence. Our secondary analysis used published data from a Japanese population and aimed to investigate the role of the GGT/HDL-C ratio in the incidence of T2DM.

METHODS

The research was a longitudinal cohort study completed by Okamura, Takuro et al. We obtained the data from the DATADRYAD website and used it for secondary analysis only. The participants recruited from a medical program called the NAGALA database received regular medical examinations and standardized questionnaires to obtain the baseline variables. Abdominal ultrasound was used to diagnose fatty liver disease. The participants were followed up, and the duration and occurrence of T2DM were documented. The GGT/HDL-C ratio evaluated at baseline served as the independent variable, while the occurrence of diabetes served as the dependent variable.

RESULTS

A total of 15,453 cases (8,419 men and 7,034 women) were included in our study. After adjusting for age, sex, BMI, DBP, SBP, ALT, AST, TG, TC, HbA1C, FPG, drinking status, smoking status, exercise status, and fatty liver, we observed that the GGT/HDL-C ratio was positively associated with the incidence of T2DM (hazard ratio = 1.005, 95% confidence interval: 1.000 to 1.010, P = 0.0667). The results were consistent when the GGT/HDL-C quartile was used as a categorical variable (P for trend < 0.00396). A curvilinear relationship with a threshold effect was identified between the GGT/HDL-C ratio and the risk of incident T2DM. On the left of the point, a one-unit increase in the GGT/HDL-C ratio was associated with a 1.5-fold increase in the risk of incident T2DM (hazard ratio 2.57, 95% confidence interval 1.20 to 5.49). On the right of the point, when GGT/HDL-C was greater than 6.53, their relationship became saturated.

CONCLUSION

The GGT/HDL-C ratio correlated with the incidence of T2DM in a curvilinear form with a threshold effect. Their positive relationship could be observed when GGT/HDL-C was less than 6.53.

Associations between the HDL-C/ApoA-I ratio and fasting glucose levels differ by glucose deciles, HDL-C/ApoA-I ratio ranges and sex

AIMS

To learn how high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A-I (ApoA-I) are associated with fasting blood glucose (FBG).

METHODS

A cross-sectional study was performed in 97,801 males and 70,773 females without known disease.

RESULTS

The ratio of HDL-C/ApoA-I is more stable for predicting fasting glucose levels than HDL-C or ApoA-I alone. In subjects with HDL-C/ApoA-I ≤ 0.9, HDL-C/ApoA-I ratios were negatively associated with FBG levels, with similar patterns between sexes, and the associations gradually strengthened along with the deciles of FBG increase. In subjects with HDL-C/ApoA-I > 0.9, FBG remained at relatively lower levels in both sexes, while the associations between the FBG level and the HDL-C/ApoA-I ratio turned from negative in the lowest five deciles to positive in the highest two deciles of FBG levels in males. Adjustment for known confounders only slightly attenuated the above association patterns. Subpopulations with HDL-C/ApoA-I ≤ 0.9 were distributed in the higher ranges of triglyceride (TG), non-HDL-C, total cholesterol (TC) and ApoA-I levels and lower ranges of HDL-C levels.

CONCLUSIONS

The HDL-C/ApoA-I ratio sorted TG, non-HDL-C, TC, ApoA-I and HDL-C levels and hence might combine more coordinating metabolic characteristics of these lipids in association with blood glucose homeostasis.

High-density lipoprotein-cholesterol and incident type 2 diabetes mellitus among African Americans: The Jackson Heart Study

AIMS

Accruing evidence suggests an association between high-density lipoprotein cholesterol (HDL-C) and incident diabetes. However, there is a paucity of data on the link between HDL-C and diabetes, especially among African Americans (AAs). We aimed to assess the association of HDL-C and its fractions with incident type 2 diabetes among AAs.

METHODS

We included Jackson Heart Study participants who attended visit 1 (2001-2004), were free from diabetes and were not treated with lipid-modifying medications. Incident diabetes was assessed at two subsequent-yearly visits (2 and 3). We cross-sectionally assessed the association of HDL-C and insulin resistance (IR) using multivariable linear models. We prospectively assessed the association of HDL-C and its fractions with incident diabetes using multivariable Cox regression models.

RESULTS

Among 2829 participants (mean age: 51.9 ± 12.4 years, 63.9% female), 487 participants (17%) developed new-onset diabetes, over a median follow-up of 8 years. In adjusted models, a higher HDL-C concentration was associated with a lower odds of IR (odds ratio [OR] per standard deviation [SD] increment: OR 0.56 [95% confidence interval, CI 0.50-0.63], p < 0.001). In adjusted models, a higher HDL-C concentration was associated with a lower risk of diabetes (HR per SD increment: 0.78 [95% CI 0.71, 0.87], p < 0.001; HR for highest vs. the lowest tertile of HDL-C was 0.56 [95% CI: 0.44, 0.71], p < 0.001).

CONCLUSION

In a sample of African-American adults not on any lipid-modifying therapy, high HDL-C concentrations were inversely associated with the risk of new-onset diabetes. These findings suggest a strong link between HDL-C metabolism and glucose regulation.

[Dysfunctional high-density lipoproteins in diabetes mellitus]

The risk of cardiovascular disease (CVD) in persons with type 2 diabetes mellitus (DM2) increases two to four times. One of the main factors increasing cardiovascular risk is dyslipidemia, which includes abnormalities in all lipoproteins, including high-density lipoproteins (HDL). The development of DM2 is accompanied not only by a decrease in the level of HDL, but also by significant changes in their structure. This leads to the transformation of native HDL into so-called dysfunctional or diabetic HDL, which loses their antiatherogenic, cardioprotective, anti-inflammatory and anti-diabetic properties. In poorly controlled diabetes mellitus HDL can not only lose its beneficial functions, but also acquire proatherogenic, proinflammatory ones. Diabetic HDL can contribute to the accumulation of such unfavorable qualities as increased proliferation, migration, and invasion of cancer cells. Given that HDL, in addition to participation in cholesterol transport, performs important regulatory functions in the body, there is reason to assume that structural modifications of HDL (oxidation, glycation, triglyceride enrichment, loss of HDL-associated enzymes, etc.) are one of the causes of vascular complications of diabetes.

High Density Lipoproteins and Diabetes

Epidemiological studies have established that a high plasma high density lipoprotein cholesterol (HDL-C) level is associated with reduced cardiovascular risk. However, recent randomised clinical trials of interventions that increase HDL-C levels have failed to establish a causal basis for this relationship. This has led to a shift in HDL research efforts towards developing strategies that improve the cardioprotective functions of HDLs, rather than simply increasing HDL-C levels. These efforts are also leading to the discovery of novel HDL functions that are unrelated to cardiovascular disease. One of the most recently identified functions of HDLs is their potent antidiabetic properties. The antidiabetic functions of HDLs, and recent key advances in this area are the subject of this review. Given that all forms of diabetes are increasing at an alarming rate globally, there is a clear unmet need to identify and develop new approaches that will complement existing therapies and reduce disease progression as well as reverse established disease. Exploration of a potential role for HDLs and their constituent lipids and apolipoproteins in this area is clearly warranted. This review highlights focus areas that have yet to be investigated and potential strategies for exploiting the antidiabetic functions of HDLs.

Association of apolipoproteins A1 and B with type 2 diabetes and fasting blood glucose: a cross-sectional study

BACKGROUND

Apolipoprotein (Apo) may be associated with type 2 diabetes (T2D), however, little is known whether or not serum apolipoproteins are correlated with fasting blood glucose (FBG) and the prevalence of T2D in Chinese populations. In this study, we examined the association of serum ApoA1, ApoB, and the ratio of ApoB/ApoA1 (ApoB/A1 ratio) with T2D and FBG level, and compared apolipoprotein indicators in predicting T2D in Chinese adults.

METHODS

A total of 1027 subjects were enrolled in this cross-sectional study. The association of ApoA1, ApoB, and ApoB/A1 ratio with T2D prevalence was determined using logistic regression models. Multivariate-analysis of covariance (ANCOVA) was performed for comparisons of the mean difference in FBG level.

RESULTS

We found that ApoB and ApoB/A1 ratio were positively associated with T2D prevalence and FBG, while inverse association was noted between ApoA1 and T2D prevalence as well as FBG. Stratified analyses for sex, age, body mass index (BMI), smoking, and alcohol consumption showed no significant difference for the association of ApoA1, ApoB, and ApoB/A1 ratio with the prevalence of T2D among subgroups (all p-interactions> 0.05). Nonetheless, ApoA1 poorly performed in predicting T2D as it provided an AUC value of 0.310 that was significantly lower than those observed for ApoB (AUC value: 0.631) and ApoB/A1 ratio (AUC value: 0.685). Finally, path analyses indicated that the association between ApoB and T2D was mediated by BMI.

CONCLUSIONS

This study reveals the association of serum ApoA1, ApoB, and ApoB/A1 ratio with T2D and FBG in Chinese adults, suggesting that ApoB and ApoB/A1 ratio may be early indicators for predicting T2D. Prospective investigation in large cohort is needed.

Apolipoprotein B and non-high-density lipoprotein cholesterol reveal a high atherogenicity in individuals with type 2 diabetes and controlled low-density lipoprotein-cholesterol

Background

Lipid-lowering therapy is guided by Low-density-lipoprotein cholesterol (LDL-c) levels, although the cardiovascular disease (CVD) risk could be better reflected by other lipid parameters. This study aimed at comparing a comprehensive lipid profile between patients with type 2 diabetes mellitus (T2DM) with LDL-c concentration within and above target.

Methods

A comprehensive lipid profile was characterized in 96 T2DM patients. The European Society of Cardiology/European Atherosclerosis Society (ESC/EAS) 2016 and 2019 Guidelines for the Management of Dyslipidemias were used to define LDL-c targets.

Results

In this population, only 28.1 and 16.7% of patients had mean LDL-c levels within target, as defined by the 2016 and 2019 guidelines, respectively. Applying the 2016 guidelines criteria, in patients with LDL-c within target, 22, 25 and 44% presented non-high-density lipoprotein cholesterol (non-HDL-c), Apolipoprotein B (ApoB) and oxidized LDL-c levels above the recommended range, respectively, whereas according to the 2019 guidelines criteria, 50, 39 and 44% of the patients with LDL-c within target had elevated high-density lipoprotein cholesterol (HDL-c), ApoB and oxidized LDL-c levels, respectively. LDL-c was strongly correlated with non-HDL-c (r = 0.850), ApoB (r = 0.656) and oxidized LDL-c (r = 0.508). Similarly, there was a strong correlation between non-HDL-c with both ApoB (r = 0.808) and oxidized LDL-c (r = 0.588).

Conclusions

These findings emphasize the limitations of only considering LDL-c concentration for cardiovascular (CV) risk assessment. Targeting only LDL-c could result in missed opportunities for CV risk reduction in T2DM patients. These data suggest that non-HDL-c, ApoB and oxidized LDL-c levels could be considered as an important part of these patients’ evaluation allowing for a more accurate estimation of CV risk and hopefully better management of these high-risk patients.

HDL and Reverse Cholesterol Transport

Cardiovascular disease, with atherosclerosis as the major underlying factor, remains the leading cause of death worldwide. It is well established that cholesterol ester-enriched foam cells are the hallmark of atherosclerotic plaques. Multiple lines of evidence support that enhancing foam cell cholesterol efflux by HDL (high-density lipoprotein) particles, the first step of reverse cholesterol transport (RCT), is a promising antiatherogenic strategy. Yet, excitement towards the therapeutic potential of manipulating RCT for the treatment of cardiovascular disease has faded because of the lack of the association between cardiovascular disease risk and what was typically measured in intervention trials, namely HDL cholesterol, which has an inconsistent relationship to HDL function and RCT. In this review, we will summarize some of the potential reasons for this inconsistency, update the mechanisms of RCT, and highlight conditions in which impaired HDL function or RCT contributes to vascular disease. On balance, the evidence still argues for further research to better understand how HDL functionality contributes to RCT to develop prevention and treatment strategies to reduce the risk of cardiovascular disease.

[Antidiabetic role of high density lipoproteins]

Disturbance in lipid metabolism can be both a cause and a consequence of the development of diabetes mellitus (DM). One of the most informative indicator of lipid metabolism is the ratio of atherogenic and antiatherogenic fractions of lipoproteins and their protein components. The review summarizes literature data and own results indicating the important role of high-density lipoprotein (HDL) and their main protein component, apolipoprotein A-I (apoA-I), in the pathogenesis of type 2 DM. On the one hand, HDL are involved in the regulation of insulin secretion by b-cells and insulin-independent absorption of glucose. On the other hand, insulin resistance and hyperglycemia lead to a decrease in HDL levels and cause modification of their protein component. In addition, HDL, possessing anti-inflammatory and mitogenic properties, provide anti-diabetic protection through systemic mechanisms. Thus, maintaining a high concentration of HDL and apoA-I in blood plasma and preventing their modification are important issues in the context of prevention and treatment of diabetes.

[HDL-C/apoA-I]: A multivessel cardiometabolic risk marker in women with T2DM

AIMS

Although women have higher high-density lipoprotein cholesterol (HDL-C) than have men, their HDL particles are also prone to become small, dense, and dysfunctional in case of type 2 diabetes mellitus (T2DM). To assess the vascular risk related to HDLs of different sizes/densities without direct measurement, we adjusted HDL-C to its main apolipoprotein (apoA-I) as [HDL-C/apoA-I]. This ratio estimates HDL sizes and provides indices as to their number, cholesterol load, and density.

METHODS

We stratified 280 Caucasian T2DM women according to [HDL-C/apoA-I] quartiles (Q) to determine how they are segregated according to cardiometabolic risk, β-cell function, glycaemic control, and vascular complications. Five parameters were derived from combined determination of HDL-C and apoA-I: HDL size, HDL number, cholesterol load per particle (pP), apoA-I pP, and HDL density.

RESULTS

An adverse cardiometabolic profile characterized QI and QII patients whose HDLs were denser and depleted in apoA-I, whereas QIII patients had HDLs with characteristics closer to those of controls. QIV patients had HDLs of supernormal size/composition and a more favourable phenotype in terms of fat distribution; insulin sensitivity (64% vs 41%), metabolic syndrome, and β-cell function (32% vs 23%); exogenous insulin (44 vs 89 U·d^-1 ); and glycaemic control (glycated haemoglobin, 56 vs 61 mmol·mol^-1 ), associated with lower prevalence of microvascular/macrovascular complications: all-cause microangiopathy 47% vs 61%; retinopathy 22% vs 34%; all-cause macroangiopathy 19% vs 31%; and coronary artery disease 6% vs 24% (P < .05).

CONCLUSION

[HDL-C/apoA-I] can stratify T2DM women according to metabolic phenotype, macrovascular and coronary damage, β-cell function, microangiopathic risk, and retinopathy. This ratio is a versatile and readily available marker of cardiometabolic status and vascular complications in T2DM women.

The role and function of HDL in patients with diabetes mellitus and the related cardiovascular risk

BACKGROUND

Diabetes mellitus (DM) is a major public health problem which prevalence is constantly raising, particularly in low- and middle-income countries. Both diabetes mellitus types (DMT1 and DMT2) are associated with high risk of developing chronic complications, such as retinopathy, nephropathy, neuropathy, endothelial dysfunction, and atherosclerosis.

METHODS

This is a review of available articles concerning HDL subfractions profile in diabetes mellitus and the related cardiovascular risk. In this review, HDL dysfunction in diabetes, the impact of HDL alterations on the risk diabetes development as well as the association between disturbed HDL particle in DM and cardiovascular risk is discussed.

RESULTS

Changes in the amount of circulation lipids, including triglycerides and LDL cholesterol as well as the HDL are frequent also in the course of DMT1 and DMT2. In normal state HDL exerts various antiatherogenic properties, including reverse cholesterol transport, antioxidative and anti-inflammatory capacities. However, it has been suggested that in pathological state HDL becomes "dysfunctional" which means that relative composition of lipids and proteins in HDL, as well as enzymatic activities associated to HDL, such as paraoxonase 1 (PON1) and lipoprotein-associated phospholipase 11 (Lp-PLA2) are altered. HDL properties are compromised in patients with diabetes mellitus (DM), due to oxidative modification and glycation of the HDL protein as well as the transformation of the HDL proteome into a proinflammatory protein. Numerous studies confirm that the ability of HDL to suppress inflammatory signals is significantly reduced in this group of patients. However, the exact underlying mechanisms remains to be unravelled in vivo.

CONCLUSIONS

The understanding of pathological mechanisms underlying HDL dysfunction may enable the development of therapies targeted at specific subpopulations and focusing at the diminishing of cardiovascular risk.

Low levels of ApoA1 improve risk prediction of type 2 diabetes mellitus

BACKGROUND

Type 2 diabetes mellitus (T2DM) has reported to be a major public health crisis in China.

OBJECTIVE

We examined the incidence of new T2DM over 4 years for association of clinical factors and lipids with development of T2DM in a community-based population.

METHODS

We included 923 Chinese subjects who participated in community-organized health checkout in both 2009 and 2013. Health history was collected; physical examination was performed; biochemistry, lipids, and glucose were measured. Of 923, 819 were confirmed without T2DM in 2009 and included in the analysis. Unadjusted and adjusted logistic regression models were used to estimate the effects of clinical factors and biomarkers on the risk of new T2DM.

RESULTS

Of 819 subjects without T2DM in 2009, 65 were identified as T2DM in 2013, 8% over 4 years. These 65 subjects, compared with those 754 without new T2DM, were older, more likely to be male and smokers. They had higher body mass index (BMI), fasting glucose, blood pressure and triglycerides, and lower levels of high-density lipoprotein-cholesterol and apolipoprotein A1 (ApoA1). Multivariate logistic regression identified larger BMI (odds ratio [OR] = 1.7; 95% confidence interval [CI], 1.22-2.39, P = .002), higher fasting glucose levels (OR = 4.2, 95% CI, 2.90-6.19, P < .001), and low levels of ApoA1 (OR = 0.51, 95% CI 0.33-0.76, P = .002) were independently associated with new T2DM. Furthermore, receiver operating characteristics curves for multivariate models for new T2DM showed that area under the curve improved from 0.87 to 0.89 when adding ApoA1 to the Framingham Diabetes Risk Scoring Model and from 0.85 to 0.89 when adding ApoA1 to a 4-variable (age, BMI, glucose, and triglycerides) Chinese model.

CONCLUSIONS

There is a high incidence of new T2DM at 8% over 4 years among Chinese. Larger BMI, higher glucose levels, and lower levels of ApoA1 are significantly and independently associated with new T2DM. Lower ApoA1 improves the risk prediction of new type 2 diabetes when it was added to the existing risk models.

Advances in high-density lipoprotein physiology: surprises, overturns, and promises

Emerging evidence strongly supports that changes in the HDL metabolic pathway, which result in changes in HDL proteome and function, appear to have a causative impact on a number of metabolic disorders. Here, we provide a critical review of the most recent and novel findings correlating HDL properties and functionality with various pathophysiological processes and disease states, such as obesity, type 2 diabetes mellitus, nonalcoholic fatty liver disease, inflammation and sepsis, bone and obstructive pulmonary diseases, and brain disorders.

Differential Association Between HDL Subclasses and the Development of Type 2 Diabetes in a Prospective Study of Japanese Americans

OBJECTIVE

Recent studies have suggested that HDL cholesterol is inversely associated with the development of type 2 diabetes. However, little is known about the association between different HDL subclasses and the risk for future type 2 diabetes.

RESEARCH DESIGN AND METHODS

The study enrolled 406 Japanese Americans (51% male) without diabetes, aged 34-75 years. Oral glucose tolerance tests were performed to determine type 2 diabetes status at baseline, 2.5 years, 5 years, and 10 years after enrollment. HDL2, HDL3, total HDL cholesterol, and visceral adipose tissue (VAT) area by computed tomography were measured at baseline.

RESULTS

In univariate analysis, total HDL and HDL2 cholesterol were inversely associated with the incidence of type 2 diabetes, but HDL3 cholesterol was not. In multivariate analysis, total HDL cholesterol (odds ratio per 1-SD increment, 0.72 [95% CI 0.52-0.995], P = 0.047) and HDL2 cholesterol (odds ratio per 1-SD increment, 0.64 [95% CI 0.44-0.93], P = 0.018) were inversely associated with the risk for type 2 diabetes independent of age, sex, BMI, waist circumference, family history of diabetes, lifestyle factors, systolic blood pressure, lipid-lowering medication use, triglyceride level, HOMA-insulin resistance, and 2-h glucose; however, HDL3 cholesterol was not associated with diabetes risk. The association between diabetes risk and total HDL and HDL2 cholesterol became insignificant after adjustment for VAT area.

CONCLUSIONS

Subjects with higher HDL2 cholesterol were at lower risk for incident type 2 diabetes, but this association was confounded by and not independent of VAT. Higher HDL3 cholesterol was not associated with diabetes risk.