Small HDL Particles Research Articles

Low levels of small HDL particles predict but do not influence risk of sepsis

BackgroundLow levels of high-density lipoprotein (HDL) cholesterol have been associated with higher rates and severity of infection. Alterations in inflammatory mediators and infection are associated with alterations in HDL cholesterol. It is unknown whether the association between HDL and infection is present for all particle sizes, and whether the observed associations are confounded by IL-6 signalling.MethodsIn the UK Biobank, ~ 270,000 individuals have data on HDL subclasses derived from nuclear magnetic resonance analysis. We estimated the association of particle count of total HDL and HDL subclasses (small, medium, large, and extra-large HDL) with sepsis, sepsis-related death, and critical care admission in a Cox regression model. We subsequently utilised genetic data from UK Biobank and FinnGen to perform Mendelian randomisation (MR) of each HDL subclass and sepsis to test for a causal relationship. Finally, we explored the role of IL-6 signalling as a potential causal driver of changes in HDL subclasses.ResultsIn observational analyses, higher particle count of small HDL was associated with protection from sepsis (Hazard ratio, HR 0.80; 95% CI 0.74–0.86, p = 4 × 10–9 comparing Quartile 4, highest quartile of HDL to Quartile 1, lowest quartile of HDL), sepsis-related death (HR 0.80; 95% CI 0.74–0.86, p = 2 × 10–4), and critical care admission with sepsis (HR 0.72 95% CI 0.60–0.85, p = 2 × 10–4). Parallel associations with other HDL subclasses were likely driven by changes in the small HDL compartment. MR analyses did not strongly support causality of small HDL particle count on sepsis incidence (Odds ratio, OR 0.98; 95% CI 0.89–1.07, p = 0.6) or death (OR 0.94, 95% CI 0.75–1.17, p = 0.56), although the estimate on critical care admission with sepsis supported protection (OR 0.73, 95% CI 0.57–0.95, p = 0.02). Bidirectional MR analyses suggested that increased IL-6 signalling was associated with reductions in both small (beta on small HDL particle count − 0.16, 95% CI − 0.10 to − 0.21 per natural log change in SD-scaled CRP, p = 9 × 10–8).and total HDL particle count (beta − 0.13, 95% CI − 0.09 to − 0.17, p = 7 × 10–10), but that the reverse effect of HDL on IL-6 signalling was largely null.ConclusionsLow number of small HDL particles are associated with increased hazard of sepsis, sepsis-related death, and sepsis-related critical care admission. However, genetic analyses did not strongly support this as causal. Instead, we demonstrate that increased IL-6 signalling, which is known to alter infection risk, could confound associations with reduced HDL particle count, and suggest this may explain part of the observed association between (small) HDL particle count and sepsis.

Plant-based diet indices and lipoprotein particle subclass profiles: A cross-sectional analysis of middle- to older-aged adults

Background and aimsPlant-based diets (PBDs) are associated with favourable lipid profiles and cardiometabolic outcomes. However, limited data regarding PBD indices (PDIs) and lipoprotein subclasses exist. We examined overall PDI, healthful PDI (hPDI) and unhealthful PDI (uPDI) associations with lipid and lipoprotein profiles. MethodsThis cross-sectional analysis includes 1,986 middle- to older-aged adults from the Mitchelstown Cohort. The PDI, hPDI and uPDI scores were calculated from validated food frequency questionnaires. Higher PDI, hPDI and uPDI scores indicate a more PBD, healthful PBD and unhealthful PBD, respectively. Lipoprotein particle size and subclass concentrations were measured using nuclear magnetic resonance spectroscopy. Relationships between PDIs and lipid and lipoprotein profiles were examined via correlation and regression analyses adjusted for covariates. ResultsIn fully adjusted regression analyses, higher PDI scores were associated with lower high-density lipoprotein (HDL) cholesterol concentrations and more triglyceride-rich lipoprotein and small very low-density lipoprotein (VLDL) particles. Higher hPDI scores were negatively associated with non-HDL cholesterol concentrations, large VLDL and small HDL particles, the Lipoprotein Insulin Resistance Index (LP-IR) score and VLDL particle size. Higher uPDI scores were associated with lower HDL cholesterol and greater triglyceride concentrations and more medium and large VLDL, total LDL, small LDL and total non-HDL particles, less large LDL and large HDL particles, a greater LP-IR score, greater VLDL particle size and smaller LDL and HDL particle size. ConclusionsThis study provides novel evidence regarding associations between PBD quality and lipoprotein subclasses. A more unhealthful PBD was robustly associated with a more pro-atherogenic lipoprotein profile.

Associations of lipoprotein subclasses with risk of all-cause and cardiovascular disease mortality in individuals with type 2 diabetes: A prospective cohort study.

Although lipoproteins are well-established risk factors for cardiovascular disease (CVD) mortality, conventional measurements failed to identify lipoprotein particle sizes. This study aimed to investigate associations of lipoprotein subclasses categorized by particle sizes with risk of all-cause and CVD mortality in individuals with type 2 diabetes. This study included 6575 individuals with type 2 diabetes from the UK Biobank. Concentrations of very low-, low-, intermediate- and high-density lipoprotein [very-low-density lipoprotein (VLDL), low-density lipoprotein (LDL), intermediate-density lipoprotein and high-density lipoprotein (HDL)] particles in 14 subclasses and lipid constituents within each subclass were measured by quantitative nuclear magnetic resonance. Multivariable-adjusted Cox proportional-hazard regression models were used to estimate the hazard ratio (HR) for per standard deviation increment of log-transformed lipoprotein subclasses with risk of mortality. All p-values were adjusted by the false discovery rate method. During a median follow-up of 11.4 years, 943 deaths were documented, including 310 CVD deaths. Small HDL particles were inversely associated with CVD mortality, with HR (95% CI) of 0.78 (0.69, 0.87), whereas very large and large HDL particles were positively associated with CVD mortality with HR (95% CI) of 1.28 (1.12, 1.45) and 1.19 (1.05, 1.35), respectively. A similar pattern was observed for all-cause mortality [small HDL particle (HR, 95% CI): 0.79, 0.74-0.85; large HDL particle: 1.15, 1.07-1.24; very large HDL particle: 1.26, 1.17-1.36]. For VLDL and LDL, very small VLDL particle was positively, while medium LDL particle was inversely associated with all-cause mortality, but not associated with CVD mortality. The pattern of association with all-cause and CVD mortality for cholesterol and triglyceride within lipoprotein particles was similar to those for lipoprotein particles themselves. The associations between lipoprotein particles, particularly HDL particles, with all-cause and CVD mortality among patients with type 2 diabetes were significantly varied by particle sizes, highlighting the importance of particle size as a lipoprotein metric in mortality risk discrimination.

Discovery and validation of circulating stroke metabolites by NMR-based analyses using patients from the MISS and UK Biobank

BackgroundStroke is a significant health issue in the United States, and identifying biomarkers for the prevention and functional recovery after an acute stroke remains the highest priority. This study aims to identify circulating metabolite signatures that may be associated with stroke pathophysiology by performing discovery and validation studies. MethodsWe performed targeted metabolomics profiling of 420 participants of the discovery dataset of Metabolome in an Ischemic Stroke Study (MISS) using high-throughput nuclear magnetic resonance (NMR) spectroscopy. A validation study of significantly altered metabolites was conducted using an independent cohort of 117,988 participants from the UK Biobank, whose metabolomics profiles were generated using the same NMR technology. Results and conclusionOur study identified 16 metabolites to be significantly perturbed during acute stroke. Amino acid phenylalanine was significantly increased, while glutamine and histidine were significantly lowered in stroke. Serum levels of apolipoprotein A-1, HDL particles, small HDL particles, essential fatty acids, and phosphatidylcholine were reduced, while ketone bodies like 3-hydroxybutyrate and acetoacetate were markedly increased in stroke. Based on the robust validation in a large independent UK Biobank dataset, some of these analytes may become clinically meaningful biomarkers to predict or prevent stroke in humans.

The Effect of Carbohydrate Restriction on Lipids, Lipoproteins, and Nuclear Magnetic Resonance-Based Metabolites: CALIBER, a Randomised Parallel Trial.

Low-carbohydrate high-fat (LCHF) diets can be just as effective as high-carbohydrate, lower-fat (HCLF) diets for improving cardiovascular disease risk markers. Few studies have compared the effects of the UK HCLF dietary guidelines with an LCHF diet on lipids and lipoprotein metabolism using high-throughput NMR spectroscopy. This study aimed to explore the effect of an ad libitum 8-week LCHF diet compared to an HCLF diet on lipids and lipoprotein metabolism and CVD risk factors. For 8 weeks, n = 16 adults were randomly assigned to follow either an LCHF (n = 8, <50 g CHO p/day) or an HCLF diet (n = 8). Fasted blood samples at weeks 0, 4, and 8 were collected and analysed for lipids, lipoprotein subclasses, and energy-related metabolism markers via NMR spectroscopy. The LCHF diet increased (p < 0.05) very small VLDL, IDL, and large HDL cholesterol levels, whereas the HCLF diet increased (p < 0.05) IDL and large LDL cholesterol levels. Following the LCHF diet alone, triglycerides in VLDL and HDL lipoproteins significantly (p < 0.05) decreased, and HDL phospholipids significantly (p < 0.05) increased. Furthermore, the LCHF diet significantly (p < 0.05) increased the large and small HDL particle concentrations compared to the HCLF diet. In conclusion, the LCHF diet may reduce CVD risk factors by reducing triglyceride-rich lipoproteins and improving HDL functionality.

327-OR: Smaller HDL Particles and ABCA1 Cholesterol Efflux Capacity Predict Incident Proliferative Retinopathy Only among Men with Type 1 Diabetes

Clinical studies have provided evidence for a potential role of dyslipidemia in the development of retinopathy in type 1 diabetes. Existing evidence, however, is generally based on conventional lipid analysis and/or cross-sectional study designs. We therefore assessed the prospective association of HDL particle concentration (HDL-P) and cholesterol efflux capacity (CEC) with incident proliferative diabetic retinopathy (PDR) in a cohort of childhood-onset type 1 diabetes. HDL-P (calibrated differential ion mobility analysis) and total and ABCA1-specific CEC (validated cell-based assays) were quantified in 186 men and 185 women with type 1 diabetes free of PDR (stereo fundus photography) at baseline (mean age 25.6 years; diabetes duration, 17.1 years). Women had higher large HDL-P than men; the concentrations of extra-small, small and medium HDL-P as well as both total and ABCA1 CEC were similar by sex. During a median follow-up of 28 years, 108 men and 100 women developed PDR. In multivariable Cox models stratified by sex, HDL-C did not predict PDR incidence in either sex. However, in addition to increased HbA1c, non-HDL-C, white blood cell count and albumin excretion rate, increased extra-small (HR=0.25, 95% CI=0.09-0.67) and small (HR=0.72, 95% CI=0.55-0.94) HDL-P concentrations and ABCA1 CEC (HR=0.80, 95% CI=0.64-0.998) negatively predicted PDR in men but not women, among whom HbA1c, hypertension and white blood cell count were the only consistent significant predictors of PDR. In conclusion, while extra-small and small HDL-P concentrations and ABCA1 CEC did not differ by sex in type 1 diabetes, they only predicted incident PDR in men, a finding similar to our previously reported results for coronary artery disease. Further research is warranted to better understand the role of HDL in the pathophysiology of PDR and why this appears to differ by sex in type 1 diabetes. Disclosure T.Costacou: None. R.G.Miller: None. T.J.Orchard: None. Funding National Institutes of Health (R01HL130153, R01DK034818)

NMR-based metabolomic profiling identifies inflammation and muscle-related metabolites as predictors of incident type 2 diabetes mellitus beyond glucose: The Di@bet.es study

AimsThe aim of this study was to combine nuclear magnetic resonance-based metabolomics and machine learning to find a glucose-independent molecular signature associated with future type 2 diabetes mellitus development in a subgroup of individuals from the Di@bet.es study. MethodsThe study group included 145 individuals developing type 2 diabetes mellitus during the 8-year follow-up, 145 individuals matched by age, sex and BMI who did not develop diabetes during the follow-up but had equal glucose concentrations to those who did and 145 controls matched by age and sex. A metabolomic analysis of serum was performed to obtain the lipoprotein and glycoprotein profiles and 15 low molecular weight metabolites. Several machine learning-based models were trained. ResultsLogistic regression performed the best classification between individuals developing type 2 diabetes during the follow-up and glucose-matched individuals. The area under the curve was 0.628, and its 95% confidence interval was 0.510–0.746. Glycoprotein-related variables, creatinine, creatine, small HDL particles and the Johnson-Neyman intervals of the interaction of Glyc A and Glyc B were statistically significant. ConclusionsThe model highlighted a relevant contribution of inflammation (glycosylation pattern and HDL) and muscle (creatinine and creatine) in the development of type 2 diabetes as independent factors of hyperglycemia.

An association of CSF apolipoprotein E glycosylation and amyloid-beta 42 in individuals who carry the APOE4 allele

Carrying the apolipoprotein E (ApoE) Ɛ4 allele is associated with an increased risk of cerebral amyloidosis and late-onset Alzheimer’s disease, but the degree to which apoE glycosylation affects its development is not clear. In a previous pilot study, we identified distinct total and secondary isoform-specific cerebral spinal fluid (CSF) apoE glycosylation profiles, with the E4 isoform having the lowest glycosylation percentage (E2 > E3 > E4). In this work, we extend the analysis to a larger cohort of individuals (n = 106), utilizing matched plasma and CSF samples with clinical measures of AD biomarkers. The results confirm the isoform-specific glycosylation of apoE in CSF, resulting from secondary CSF apoE glycosylation patterns. CSF apoE glycosylation percentages positively correlated with CSF Aβ42 levels (r = 0.53, p < 0.0001). These correlations were not observed for plasma apoE glycosylation. CSF total and secondary apoE glycosylation percentages also correlated with the concentration of CSF small high-density lipoprotein particles (s-HDL-P), which we have previously shown to be correlated with CSF Aβ42 levels and measures of cognitive function. Desialylation of apoE purified from CSF showed reduced Aβ42 degradation in microglia with E4 > E3 and increased binding affinity to heparin. These results indicate that apoE glycosylation has a new and important role in influencing brain Aβ metabolism and can be a potential target of treatment.

Estimated sdLDL-C for predicting high-risk coronary plaque features in psoriasis: a prospective observational study

BackgroundPsoriasis (PSO) is a skin disorder with systemic inflammation and high coronary artery disease risk. A distinct lipid phenotype occurs in psoriasis, which is characterized by high plasma triglycerides (TGs) with typically normal or even low LDL-C. The extent to which cholesterol on LDL subfractions, such as small dense LDL-C (sdLDL-C), are associated with vulnerable coronary plaque characteristics in PSO remains elusive.MethodsA recently developed equation for estimating sdLDL-C from the standard lipid panel was utilized in a PSO cohort (n = 200) with 4-year follow-up of 75 subjects. Coronary plaque burden was assessed by quantitative coronary computed tomography angiography (CCTA). Multivariate regression analyses were used for establishing associations and prognostic value of estimated sdLDL-C.ResultsEstimated sdLDL-C was positively associated with non-calcified burden (NCB) and fibro-fatty burden (FFB), which remained significant after multivariate adjustment for NCB (β = 0.37; P = 0.050) and LDL-C adjustment for FFB (β = 0.29; P < 0.0001). Of note, total LDL-C calculated by the Friedewald equation was not able to capture these associations in the study cohort. Moreover, in the regression modelling estimated sdLDL-C was significantly predicting necrotic burden progression over 4 years follow-up (P = 0.015), whereas LDL-C did not. Finally, small LDL particles (S-LDLP) and small HDL particles (S-HDLP), along with large and medium TG-rich lipoproteins (TRLPs) had the most significant positive correlation with estimated sdLDL-C.ConclusionsEstimated sdLDL-C has a stronger association than LDL-C with high-risk features of coronary atherosclerotic plaques in psoriasis patients.Clinical trial registrationURL: https://www.clinicaltrials.gov. Unique identifiers: NCT01778569

Small Dense LDL Level and LDL/HDL Distribution in Acute Coronary Syndrome Patients

A total of 205 ACS patients and 100 healthy control subjects were enrolled. LDL particle size and LDL and HDL subclass distributions were measured using Quantimetric Lipoprint® linear polyacrylamide gel electrophoresis. Lipid ratios (total cholesterol, LDL cholesterol, non-HDL cholesterol, and HDL cholesterol) were determined to calculate the atherogenic index of plasma (AIP), the atherogenic coefficient (AC), Castelli's Risk-I (CR-I), and Castelli's Risk-II (CR-II). Receiver operating characteristic (ROC) curve analyses and area under the curve (AUC) were used to assess the predictive value of sdLDL as a marker for cardiovascular disease. The ACS patients, compared to the healthy control subjects, displayed an alteration of LDL particle distribution, with a significant increase in sdLDL serum concentrations (0.303 ± 0.478 mmol/L vs. 0.0225 ± 0.043 mmol/L, respectively, p < 0.001). The sdLDL levels had a high discrimination accuracy [AUC = 0.847 ± 0.0353 (95% CI 0.778 to 0.916, p < 0.0001)]. The best predictive cutoff value of ACS determined with the maximum Youden index (J) [(sensitivity + specificity) - 1 = 0.60] was 0.038 mmol/L. A Spearman correlation analysis showed that sdLDL levels were moderately but significantly and positively correlated with AC and CR-I (r = 0.37, p < 0.001) and weakly but significantly correlated with PAI and CR-II; r = 0.32 (p < 0.001) and r = 0.30 (p < 0.008), respectively. The subclass distribution of HDL particles from ACS patients was also altered, with a decrease in large HDL particles and an increase in small HDL particles compared to HDL from healthy control subjects. Due to their high atherogenicity, sdLDL levels could be used as a valuable marker for the prediction cardiovascular events.

Aberrations in the early pregnancy serum metabolic profile in women with prediabetes at two years postpartum

IntroductionAberrations in circulating metabolites have been associated with diabetes and cardiovascular risk.ObjectivesTo investigate if early and late pregnancy serum metabolomic profiles differ in women who develop prediabetes by two years postpartum compared to those who remain normoglycemic.MethodsAn NMR metabolomics platform was used to measure 228 serum metabolite variables from women with pre-pregnancy overweight in early and late pregnancy. Co-abundant groups of metabolites were compared between the women who were (n = 40) or were not (n = 138) prediabetic at two years postpartum. Random Forests classifiers, based on the metabolic profiles, were used to predict the prediabetes status, and correlations of the metabolites to glycemic traits (fasting glucose and insulin, HOMA2-IR and HbA1c) and hsCRP at postpartum were evaluated.ResultsWomen with prediabetes had higher concentrations of small HDL particles, total lipids in small HDL, phospholipids in small HDL and free cholesterol in small HDL in early pregnancy (p = 0.029; adj with pre-pregnancy BMI p = 0.094). The small HDL related metabolites also correlated positively with markers of insulin resistance at postpartum. Similar associations were not detected for metabolites in late pregnancy. A Random Forests classifier based on serum metabolites and clinical variables in early pregnancy displayed an acceptable predictive power for the prediabetes status at postpartum (AUROC 0.668).ConclusionElevated serum concentrations of small HDL particles in early pregnancy associate with prediabetes and insulin resistance at two years postpartum. The serum metabolic profile during pregnancy might be used to identify women at increased risk for type 2 diabetes.

Metabolic profiling of MRI-measured liver fat in the UK Biobank.

Liver fat associates with obesity-related metabolic disturbances and may precede incident diseases. Metabolomic profiles of liver fat in the UK Biobank were investigated. Regression models assessed the associations between 180 metabolites and proton density liver fat fraction (PDFF) measured 5 years later through magnetic resonance imaging, as the difference (in SD units) of each log metabolite measure with 1-SDhigher PDFF among those without chronic disease and not taking statins, and by diabetes and cardiovascular diseases. After accounting for confounders, multiple metabolites were associated positively with liver fat (p < 0.0001 for 152 traits), particularly extremely large and very large lipoprotein particle concentrations, very low-density lipoprotein triglycerides, small high-density lipoprotein particles, glycoprotein acetyls, monounsaturated and saturated fatty acids, and amino acids. Extremely large and large high-density lipoprotein concentrations had strong inverse associations with liver fat. Associations were broadly comparable among those with versus without vascular metabolic conditions, although negative, rather than positive, associationswere observed between intermediate-density and large low-density lipoprotein particles among those with BMI≥25 kg/m2 , diabetes, or cardiovascular diseases. Metabolite principal components showed a 15% significant improvement in risk prediction for PDFF relative to BMI, which was twice as great (but nonsignificant) compared with conventional high-densitylipoproteincholesterol and triglycerides. Hazardous metabolomic profiles are associated with ectopic hepatic fat and are relevant to risk of vascular-metabolic disease.

Abstract P524: Metabolic Vulnerability and Frailty for Risk Stratification in Heart Failure: A Community Cohort Study

Introduction: Over 6 million people in the U.S. have heart failure (HF), less than half are expected to survive beyond 5 years. The need to better stratify mortality risk in HF is recognized. Frailty is associated with mortality in HF but not routinely measured clinically. As frailty is linked to inflammation and malnutrition, we hypothesized that the Metabolic Vulnerability Index (MVX) a multimarker score of systemic inflammation (small HDL particles, GlycA) and malnutrition (leucine, valine, isoleucine, citrate), could serve as a biomarker of frailty to predict mortality risk. Methods: Clinical data and plasma were collected from 1,389 patients from a HF community cohort between 2003-2012. We measured frailty using the Rockwood Index as the proportion of deficits present out of 32 physical limitations and comorbidities. MVX was calculated from the nuclear magnetic resonance LipoProfile® test. Patients were categorized by frailty (0-0.15; 0.16-0.27; 0.28-0.78) and MVX (33.4-50, 50-60, 60-70, 70-85.8) cutpoints. Cox models estimated the association of frailty and MVX assignment with mortality, adjusted for Meta-Analysis Global Group in Chronic HF (MAGGIC) score, a validated clinical risk score for HF mortality. Results: Frailty and MVX scores were available in 985 patients (median age 77, IQR: 67-84; 48% women). Higher frailty was associated with higher MVX (p-trend &lt; 0.001). The highest frailty and MVX groups experienced large increases in risk of death, after adjustment for MAGGIC score (HR=3.3, 95% CI=2.6-4.2) and (HR=2.7, 95% CI=2.1-3.5), respectively. When adjusted for one another and MAGGIC score, MVX and frailty associations with death were only minimally attenuated: frailty (HR=3.2, 95% CI=2.5-4.0) and MVX (HR=2.4, 95% CI=1.9-3.2) (Figure 1). Conclusion: In this community cohort of patients with HF, frailty and MVX are positively associated with one another. However, both indicators are independently associated with an increased risk of death and can contribute to risk stratification.

Differences in HDL-related mortality risk between individuals with and without hypertension: A prospective cohort study in UK Biobank.

Very high levels of high-density lipoprotein cholesterol (HDL-C) has been paradoxically linked to increased mortality risk. The present study aimed to examine associations of HDL-C and varied sizes of HDL particle (HDL-P) with mortality risk stratified by hypertension. This prospective cohort study included 429 792 participants (244 866 with hypertension and 184 926 without hypertension) from the UK Biobank. During a median follow-up of 12.7 years, 23 993 (9.8%) and 8142 (4.4%) deaths occurred among individuals with and without hypertension, respectively. A U-shaped association of HDL-C with all-cause mortality was observed in individuals with hypertension after multivariable adjustment, whereas an L-shape was observed in individuals without hypertension. Compared to individuals with normal HDL-C of 50 to 70 mg/dL, those with very high HDL-C levels (> 90 mg/dL) had a significantly higher risk of all-cause mortality among individuals with hypertension (hazard ratio, 1.47; 95% confidence interval, 1.35-1.61), but not among those without hypertension (1.05, 0.91-1.22). As for HDL-P, among individuals with hypertension, larger size of HDL-P was positively whereas smaller HDL-P was negatively associated with all-cause mortality. After additional adjustment for larger HDL-P in the model, the U-shaped association between HDL-C and mortality risk altered to L-shape among individuals with hypertension. The increased risk of mortality associated with very high HDL-C existed only in individuals with hypertension, but not in those without hypertension. Moreover, the increased risk at high HDL-C levels in hypertension was likely driven by larger HDL-P.

Association of Advanced Lipoprotein Subpopulation Profiles with Insulin Resistance and Inflammation in Patients with Type 2 Diabetes Mellitus.

Plasma lipoproteins exist as several subpopulations with distinct particle number and size that are not fully reflected in the conventional lipid panel. In this study, we sought to quantify lipoprotein subpopulations in patients with type 2 diabetes mellitus (T2DM) to determine whether specific lipoprotein subpopulations are associated with insulin resistance and inflammation markers. The study included 57 patients with T2DM (age, 61.14 ± 9.99 years; HbA1c, 8.66 ± 1.60%; mean body mass index, 35.15 ± 6.65 kg/m2). Plasma lipoprotein particles number and size were determined by nuclear magnetic resonance spectroscopy. Associations of different lipoprotein subpopulations with lipoprotein insulin resistance (LPIR) score and glycoprotein acetylation (GlycA) were assessed using multi-regression analysis. In stepwise regression analysis, VLDL and HDL large particle number and size showed the strongest associations with LPIR (R2 = 0.960; p = 0.0001), whereas the concentrations of the small VLDL and HDL particles were associated with GlycA (R2 = 0.190; p = 0.008 and p = 0.049, respectively). In adjusted multi-regression analysis, small and large VLDL particles and all sizes of lipoproteins independently predicted LPIR, whereas only the number of small LDL particles predicted GlycA. Conventional markers HbA1c and Hs-CRP did not exhibit any significant association with lipoprotein subpopulations. Our data suggest that monitoring insulin resistance-induced changes in lipoprotein subpopulations in T2DM might help to identify novel biomarkers that can be useful for effective clinical intervention.

High-density lipoprotein subclasses and cardiovascular disease and mortality in type 2 diabetes: analysis from the Hong Kong Diabetes Biobank

ObjectiveHigh-density lipoproteins (HDL) comprise particles of different size, density and composition and their vasoprotective functions may differ. Diabetes modifies the composition and function of HDL. We assessed associations of HDL size-based subclasses with incident cardiovascular disease (CVD) and mortality and their prognostic utility.Research design and methodsHDL subclasses by nuclear magnetic resonance spectroscopy were determined in sera from 1991 fasted adults with type 2 diabetes (T2D) consecutively recruited from March 2014 to February 2015 in Hong Kong. HDL was divided into small, medium, large and very large subclasses. Associations (per SD increment) with outcomes were evaluated using multivariate Cox proportional hazards models. C-statistic, integrated discrimination index (IDI), and categorial and continuous net reclassification improvement (NRI) were used to assess predictive value.ResultsOver median (IQR) 5.2 (5.0–5.4) years, 125 participants developed incident CVD and 90 participants died. Small HDL particles (HDL-P) were inversely associated with incident CVD [hazard ratio (HR) 0.65 (95% CI 0.52, 0.81)] and all-cause mortality [0.47 (0.38, 0.59)] (false discovery rate < 0.05). Very large HDL-P were positively associated with all-cause mortality [1.75 (1.19, 2.58)]. Small HDL-P improved prediction of mortality [C-statistic 0.034 (0.013, 0.055), IDI 0.052 (0.014, 0.103), categorical NRI 0.156 (0.006, 0.252), and continuous NRI 0.571 (0.246, 0.851)] and CVD [IDI 0.017 (0.003, 0.038) and continuous NRI 0.282 (0.088, 0.486)] over the RECODe model.ConclusionSmall HDL-P were inversely associated with incident CVD and all-cause mortality and improved risk stratification for adverse outcomes in people with T2D. HDL-P may be used as markers for residual risk in people with T2D.

Lower levels of small HDL particles associated with increased infectious disease morbidity and mortality: a population-based cohort study of 30 195 individuals.

Low levels of HDL cholesterol have been associated with increased risk of infectious disease morbidity and mortality. Nuclear magnetic resonance (NMR) spectroscopy permits the measurement of HDL particle count and allows further subclassification according to particle size. We tested the hypothesis that low number of different HDL subfractions is associated with increased infectious disease morbidity and mortality. HDL particle counts were measured using NMR spectroscopy in 30 195 individuals aged 22-99 years from the Copenhagen General Population Study. Using multiple-event Cox regression and cause-specific hazard models, we assessed risk of hospitalizations due to infection and infectious disease-related death, from 2003 through 2018. During follow-up, 9303 individuals had one or more infectious disease events, and 1558 experienced infectious disease-related death. In multifactorial adjusted analyses, low number of small and medium HDL particles was associated with increased risk of any infection and infectious disease-related death, whereas low number of large and extra-large HDL particles was not. A very high number of small and medium HDL particles was also associated with increased risk of any infection, but not with infectious disease-related death. For small and medium HDL particles and compared to individuals in the 91-95th percentile, hazard ratios (HRs) in individuals in the lowest percentile were 2.31 (95% confidence interval: 1.75, 3.05) for any infection and 3.23 (2.08, 5.02) for infectious disease-related death. For the highest percentile, corresponding HRs were 1.36 (1.07, 1.74) and 1.06 (0.57, 1.98), respectively. Individuals in the lowest percentile had increased risk of pneumonia (HR: 1.86; 95% confidence interval: 1.30, 2.65), sepsis (2.17; 1.37, 3.35), urinary tract infection (1.76; 1.17, 2.63), skin infection (1.87; 1.24, 2.81), gastroenteritis (1.78; 1.01, 3.16), and other infections (2.57; 1.28, 5.16). Low number of the small HDL particles was associated with increased infectious disease morbidity and mortality.

Free triiodothyronine levels and age influences the metabolic profile and COVID-19 severity parameters in euthyroid and levothyroxine-treated patients.

Metabolic reprogramming is required to fight infections and thyroid hormones are key regulators of metabolism. We have analyzed in hospitalized COVID-19 patients: 40 euthyroid and 39 levothyroxine (LT4)-treated patients in the ward and 29 euthyroid and 9 LT4-treated patients in the intensive care unit (ICU), the baseline characteristics, laboratory data, thyroid-stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), the FT3/FT4 ratio, 11 antiviral cytokines and 74 metabolomic parameters. No evidence for significant differences between euthyroid and LT4-treated patients were found in the biochemical, metabolomic and cytokines parameters analyzed. Only TSH (p=0.009) and ferritin (p=0.031) showed significant differences between euthyroid and LT4-treated patients in the ward, and TSH (p=0.044) and FT4 (p=0.012) in the ICU. Accordingly, severity and mortality were similar in euthyroid and LT4-treated patients. On the other hand, FT3 was negatively related to age (p=0.012), independently of sex and body mass index in hospitalized COVID-19 patients. Patients with low FT3 and older age showed a worse prognosis and higher levels of the COVID-19 severity markers IL-6 and IL-10 than patients with high FT3. IL-6 negatively correlated with FT3 (p=0.023) independently of age, body mass index and sex, whereas IL-10 positively associated with age (p=0.035) independently of FT3, body mass index and sex. A metabolomic cluster of 6 parameters defined low FT3 ward patients. Two parameters, esterified cholesterol (p=4.1x10-4) and small HDL particles (p=6.0x10-5) correlated with FT3 independently of age, body mass index and sex, whereas 3-hydroxybutyrate (p=0.010), acetone (p=0.076), creatinine (p=0.017) and high-density-lipoprotein (HDL) diameter (p=8.3x10-3) were associated to FT3 and also to age, with p-values of 0.030, 0.026, 0.017 and 8.3x10-3, respectively. In conclusion, no significant differences in FT3, cytokines, and metabolomic profile, or in severity and outcome of COVID-19, were found during hospitalization between euthyroid patients and hypothyroid patients treated with LT4. In addition, FT3 and age negatively correlate in COVID-19 patients and parameters that predict poor prognosis were associated with low FT3, and/or with age. A metabolomic cluster indicative of a high ketogenic profile defines non-critical hospitalized patients with low FT3 levels.

Abstract 14231: Egg Consumption Induces Sex-Specific Changes in High-Density Lipoprotein Composition and Function

Introduction: HDL composition is an important determinant of cardioprotective functions. Importantly, sex-specific differences in HDL composition and function have been observed. While diet represents a promising therapeutic strategy to optimize HDL composition and function, it is unclear whether the capacity to modulate HDL profiles through diet is sex-specific. Hypothesis: We hypothesized that daily consumption of different egg-based diets, which differentially impact HDL particle profiles and efflux capacity, would alter HDL composition and function in a sex-dependent manner. Methods: Healthy men and women (n = 26) participated in a 16-week randomized, crossover intervention trial (NCT03577223), in which they consumed a 4-week egg-free diet, followed by a 4-week diet containing either 3 whole eggs or 3 egg whites per day. Participants then followed a 4-week egg-free washout diet, before switching to the alternative whole egg or egg white diet treatment. Fasted blood samples were collected after each diet period to determine HDL particle profiles by NMR, serum paraoxonase 1 (PON1) lactonase activity, cholesterol efflux capacity, and HDL lipid and protein composition. Results: We observed sex-specific differences in HDL profiles following egg intake. In women, whole egg intake increased HDL-phosphatidylcholine and phosphatidylethanolamine content, whereas HDL-phosphatidylinositol and sphingomyelin were increased and decreased, respectively, in men. Similarly, egg diets differentially and sex-dependently altered HDL proteins implicated in cholesterol efflux capacity and cardiovascular disease risk. Whole egg intake increased HDL-apoAII, apoL1, apoM, and lowered serum amyloid P compared to the egg-free and egg white diets in women, whereas HDL-PON3 was increased by egg white intake in men. PON1 activity and cholesterol efflux capacity were increased following whole egg intake in women only. Independent of sex, changes in cholesterol efflux capacity between the egg white and whole egg periods were positively correlated with the number of total and small HDL particles. Conclusions: Modulation of HDL profiles by diet are sex-specific, with whole egg intake promoting more significant changes in HDL composition and function in women.

OR02-1 Differences in HDL Particle Composition in Patients with Nonalcoholic Fatty Liver Disease (NAFLD) and Advanced Liver Fibrosis May Explain Higher Cardiovascular Risk

Abstract The severity of liver fibrosis in patients with NAFLD is a strong predictor of cardiovascular mortality, independently of other well-known cardiovascular risk factors. However, the exact mechanisms leading to cardiovascular disease in patients with advanced liver fibrosis remain incompletely understood. As many of the apolipoproteins are synthesized in the liver, we hypothesized that lipoprotein composition may explain the association between liver disease and cardiovascular disease. Patients (n=185) underwent a liver proton magnetic resonance spectroscopy (1H-MRS) to measure intrahepatic triglyceride accumulation and a percutaneous liver biopsy if they had NAFLD. Advanced lipid testing and lipoprotein subfractions were measured by ion mobility. ApoA-I containing particles (i.e., HDL) were isolated and a novel targeted proteomic approach utilizing multiple reaction monitoring (MRM) by liquid chromatography and tandem mass spectrometry (LC-MS/MS) was undertaken to measure HDL-bound proteins that are associated with lipid metabolism. Forty-five patients did not have NAFLD by 1H-MRS and were used as controls for comparisons. One-hundred and forty patients had a liver biopsy, and 26 were diagnosed with advanced fibrosis. Patients with vs. without advanced fibrosis had similar clinical characteristics (Age: 54±9 vs. 52±11 years; sex: 77% vs. 76% males; BMI: 34.2±4.3 vs. 34.5±4.6 kg/m2). Patients with advanced fibrosis had lower HDL-C (34±8 vs. 38±9 mg/dl, p=0.024) and higher A1c (7.3±1.3% vs. 6.5±1.0%, p&amp;lt;0.001). No differences were observed in LDL or VLDL particle number or size between the groups. Patients with advanced fibrosis showed a mild reduction in HDL particle number, mainly driven by a reduction of small HDL particles (17269±3705 vs. 19057±4052 nmol/L, p=0.042). Despite this small difference in HDL particle number, a significant difference was observed in the proteomic signature of these particles. A panel of twenty-eight HDL-bound proteins were targeted and quantified by MRM LC-MS/MS. After adjustment for multiple comparisons based on a false discovery rate set at 10% (method of Benjamini-Krieger-Yekutieli), five proteins were found to be decreased in patients with advanced fibrosis (ApoC-I, ApoC-IV, ApoM, LCAT, and SAA4; all p&amp;lt;0.017). No differences were observed in these proteins in patients with vs. without NAFLD or steatohepatitis (NASH). The pCAD index [range from 0-100] is a well-validated model based on measurement of 5 HDL-associated apolipoproteins (Apolipoproteins A-I, C-I, C-II, C-III, and C-IV) that is associated with presence of coronary artery disease and cardiovascular mortality. We observed a stepwise increase in pCAD index with every stage of fibrosis among patients with NAFLD (F0: 84±3; F1: 88±3; F2: 90±6; F3-4: 97±1, p=0.037). Conclusion Patients with NAFLD with advanced fibrosis showed significant differences in the apolipoproteomic composition of HDL particles, and this translated into increased cardiovascular risk based on pCAD index. Different lipoprotein composition and function may explain the link between liver disease and increased cardiovascular mortality in these patients. Presentation: Saturday, June 11, 2022 11:30 a.m. - 11:45 a.m.