Ethnic Variation in Lipid Profile and Its Associations with Body Composition and Diet: Differences Between Iranians, Indians and Caucasians Living in Australia

The high-density lipoprotein cholesterol (HDL-C)-concentration-dependent association between anti-inflammatory capacity and sepsis: A single-center cross-sectional study

INTRODUCTION

Known to have pleiotropic functions, high-density lipoprotein (HDL) helps to regulate systemic inflammation during sepsis. As preserving HDL-C level is a promising therapeutic strategy for sepsis, the interaction between HDL and sepsis worth further investigation. This study aimed to determine the impact of sepsis on HDL's anti-inflammatory capacity and explore its correlations with disease severity and laboratory parameters.

METHODS AND MATERIALS

We enrolled 80 septic subjects admitted to the intensive care unit and 50 controls admitted for scheduled coronary angiography in this cross-sectional study. We used apolipoprotein-B depleted (apoB-depleted) plasma to measure the anti-inflammatory capacity of HDL-C. ApoB-depleted plasma's anti-inflammatory capacity is defined as its ability to suppress tumor necrosis factor-α-induced vascular cell adhesion molecule-1 (VCAM-1) expression in human umbilical-vein endothelial cells. A subgroup analysis was conducted to investigate in septic subjects according to disease severity.

RESULTS

ApoB-depleted plasma's anti-inflammatory capacity was reduced in septic subjects relative to controls (VCAM-1 mRNA fold change: 50.1% vs. 35.5%; p < 0.0001). The impairment was more pronounced in septic subjects with than in those without septic shock (55.8% vs. 45.3%, p = 0.0022). Both associations were rendered non-significant with the adjustment for the HDL-C level. In sepsis patients, VCAM-1 mRNA fold change correlated with the SOFA score (Spearman's r = 0.231, p = 0.039), lactate level (r = 0.297, p = 0.0074), HDL-C level (r = -0.370, p = 0.0007), and inflammatory markers (C-reactive protein level: r = 0.441, p <0.0001; white blood cell: r = 0.353, p = 0.0013).

CONCLUSION

ApoB-depleted plasma's anti-inflammatory capacity is reduced in sepsis patients and this association depends of HDL-C concentration. In sepsis patients, this capacity correlates with disease severity and inflammatory markers. These findings explain the prognostic role of the HDL-C level in sepsis and indirectly support the rationale for targeting HDL-C as sepsis treatment.

A novel equation for the estimation of low-density lipoprotein cholesterol in the Saudi Arabian population: a derivation and validation study

Low-density lipoprotein cholesterol (LDL-C) is typically estimated by the Friedewald equation to guide atherosclerotic cardiovascular disease (ASCVD) management despite its flaws. Martin-Hopkins and Sampson-NIH equations were shown to outperform Friedewald's in various populations. Our aim was to derive a novel equation for accurate LDL-C estimation in Saudi Arabians and to compare it to Friedewald, Martin-Hopkins and Sampson-NIH equations. This is a cross-sectional study on 2245 subjects who were allocated to 2 cohorts; a derivation (1) and a validation cohort (2). Cohort 1 was analyzed in a multiple regression model to derive an equation (equationD) for estimating LDL-C. The agreement between the measured (LDL-CDM) and calculated levels was tested by Bland-Altman analysis, and the biases by absolute error values. Validation of the derived equation was carried out across LDL-C and triglyceride (TG)-stratified groups. The mean LDL-CDM was 3.10 ± 1.07 and 3.09 ± 1.06 mmol/L in cohorts 1 and 2, respectively. The derived equation is: LDL-CD = 0.224 + (TC × 0.919) - (HDL-C × 0.904) - (TG × 0.236) - (age × 0.001) - 0.024. In cohort 2, the mean LDL-C (mmol/L) was estimated as 3.09 ± 1.06 by equationD, 2.85 ± 1.12 by Friedewald, 2.95 ± 1.09 by Martin-Hopkins, and 2.93 ± 1.11 by Sampson-NIH equations; statistically significant differences between direct and calculated LDL-C was observed with the later three equations (P < 0.001). Bland-Altman analysis showed the lowest bias (0.001 mmol/L) with equationD as compared to 0.24, 0.15, and 0.17 mmol/L with Friedewald, Martin-Hopkins, and Sampson-NIH equations, respectively. The absolute errors in all guideline-stratified LDL-C categories was the lowest with equationD, which also showed the best classifier of LDL-C according to guidelines. Moreover, equationD predicted LDL-C levels with the lowest error with TG levels up to 5.63 mmol/L. EquationD topped the other equations in estimating LDL-C in Saudi Arabians as it could permit better estimation when LDL-C is < 2.4 mmol/L, in familial hyperlipidemia, and in hypertriglyceridemia, which improves cardiovascular outcomes in high-risk patients. We recommend further research to validate equationD in a larger dataset and in other populations.

Body composition and metabolic parameters in men with chronic traumatic paraplegia - A pilot study from India

OBJECTIVE

To study body composition, measures of insulin resistance and dyslipidemia in Indian men with paraplegia as compared to age and body mass index (BMI) matched able-bodied men.

DESIGN

Cross sectional study.

SETTING

Departments of Physical Medicine and Rehabilitation and Endocrinology.

PARTICIPANTS

Males aged 18-45 years with chronic traumatic paraplegia versus age and BMI-matched able-bodied men.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Measures of body composition such as total body fat, lean mass, regional adiposity using dual energy x-ray absorptiometry (DXA), metabolic profile and insulin resistance.

RESULTS

Subjects with paraplegia (n = 43), compared to controls (n = 36), had higher %Fat mass (FM) (25.5 (21.2-28.9) vs 20.2 (15.9-22.2); P < 0.01), lower trunk to leg ratio (0.66 (0.51-0.73) vs 0.87 (0.72-0.94); P < 0.01), lower lean mass index (14.38 (2.57) vs 17.80 (2.34); P < 0.01) and lower appendicular lean mass index (5.81 ± 1.26 vs 8.17 ± 1.12; P < 0.01). Fasting blood glucose (mg/dl) was higher (89.0(81.5-96.5) vs 80.0 (74.5-88.2); P < 0.01), Homeostasis model assessment of insulin resistance was higher (1.33 (1.03-2.12) vs 0.94 (0.52-1.78); P = 0.02), Quantitative insulin sensitivity check index (QUICKI) was lower (0.36 ± 0.04 vs 0.38 ± 0.05; P = 0.02) and HDL-C was lower (33.00 (30.00-42.75) vs 38.50 (33.00-43.25); P < 0.02) in cases compared to controls. QUICKI correlated positively with HDL-C and negatively with %FM, estimated VAT volume and TG. Trunk to leg ratio correlated positively with TG even after controlling for %FM.

CONCLUSION

Men with chronic paraplegia had lower lean mass, higher total and regional fat mass, increased insulin resistance and low HDL-C when compared with BMI-matched able-bodied controls. Both total and regional adiposity correlated with poor metabolic profile.

A Modern Approach to Dyslipidemia

Lipid disorders involving derangements in serum cholesterol, triglycerides, or both are commonly encountered in clinical practice and often have implications for cardiovascular risk and overall health. Recent advances in knowledge, recommendations, and treatment options have necessitated an updated approach to these disorders. Older classification schemes have outlived their usefulness, yielding to an approach based on the primary lipid disturbance identified on a routine lipid panel as a practical starting point. Although monogenic dyslipidemias exist and are important to identify, most individuals with lipid disorders have polygenic predisposition, often in the context of secondary factors such as obesity and type 2 diabetes. With regard to cardiovascular disease, elevated low-density lipoprotein cholesterol is essentially causal, and clinical practice guidelines worldwide have recommended treatment thresholds and targets for this variable. Furthermore, recent studies have established elevated triglycerides as a cardiovascular risk factor, whereas depressed high-density lipoprotein cholesterol now appears less contributory than was previously believed. An updated approach to diagnosis and risk assessment may include measurement of secondary lipid variables such as apolipoprotein B and lipoprotein(a), together with selective use of genetic testing to diagnose rare monogenic dyslipidemias such as familial hypercholesterolemia or familial chylomicronemia syndrome. The ongoing development of new agents-especially antisense RNA and monoclonal antibodies-targeting dyslipidemias will provide additional management options, which in turn motivates discussion on how best to incorporate them into current treatment algorithms.

Modeling cholesterol metabolism and atherosclerosis

Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of morbidity and mortality among Western populations. Many risk factors have been identified for ASCVD; however, elevated low-density lipoprotein cholesterol (LDL-C) remains the gold standard. Cholesterol metabolism at the cellular and whole-body level is maintained by an array of interacting components. These regulatory mechanisms have complex behavior. Likewise, the mechanisms which underpin atherogenesis are nontrivial and multifaceted. To help overcome the challenge of investigating these processes mathematical modeling, which is a core constituent of the systems biology paradigm has played a pivotal role in deciphering their dynamics. In so doing models have revealed new insights about the key drivers of ASCVD. The aim of this review is fourfold; to provide an overview of cholesterol metabolism and atherosclerosis, to briefly introduce mathematical approaches used in this field, to critically discuss models of cholesterol metabolism and atherosclerosis, and to highlight areas where mathematical modeling could help to investigate in the future. This article is categorized under: Cardiovascular Diseases > Computational Models.

Valproate is associated with early decrease of high-density lipoprotein cholesterol levels in the psychiatric population

Few studies have evaluated the influence of valproate on the deterioration of the lipid profile in psychiatric patients. This observational study aimed to compare the evolution of metabolic parameters in a sample of adult patients starting valproate (n = 39) with a control group (n = 39) of patients starting aripiprazole, a drug associated with a low risk of metabolic deterioration. Data were obtained from a prospective study including psychiatric patients with metabolic parameters monitored during the first year of treatment. During the first month of treatment with valproate (median: 31 days [IQR: 25-36]), mean body mass index increased significantly (from 24.8 kg/m² at baseline to 25.2 kg/m² after one month; P = .03) and mean HDL-C levels decreased significantly (from 1.39 mmol/L to 1.27 mmol/L; P = .02). In comparison, these metabolic variables remained stable during the first month of treatment with aripiprazole. The proportion of patients with early (ie during the first month of treatment) HDL-C decrease of ≥ 5% was significantly higher under valproate (54%) than aripiprazole (15%) treatment (P < .001). These findings remind the importance of a prospective metabolic monitoring in patients who initiate valproate treatment. Further research should be conducted on larger samples and should focus on finding effective interventions to prevent such metabolic adverse effects.

Comparison of early cardiovascular risk among Brazilian and African university students

Cardiovascular diseases are among the main causes of mortality worldwide, and dyslipidemia is a principal factor risk. Hence the study of biochemical markers is necessary for early diagnosis.

OBJECTIVES

Evaluate biomarkers to diagnose the risks of cardiovascular diseases in healthy Brazilian and African young adults.

DESIGN & METHODS

Weight, height, waist circumference, percentage of body fat and systemic blood pressure were measured; and fasting blood samples were taken for biochemical analysis. Triglycerides, total cholesterol, HDL-c, and apolipoproteins A-I and B were measured on automated equipment using commercially available kits, in addition to the tests of antioxidant capacity of HDL and the enzymatic activity of Paraoxonase 1.

RESULTS

After statistical analysis, it was found that BMI, WC, fat (%), triglycerides, ApoB/ApoA-I ratio and Vmax were higher in Brazilians, while HDL-c, ApoA-I, Lag Time, Vmax and PON1 activity were higher in Africans. In Brazilians, the ApoB/ApoA-I ratio was related to obesity factors and lipid profile, but in Africans it was related only to lipids. The antioxidant capacity of HDL and PON1 activity was better in Africans. Through independence testing, we observed an association with moderate risk of myocardial infarction with gender in Africans. In the binary logistic regression analysis, it was found that men in general - and particularly African men - have higher risk of myocardial infarction than women; Odds Ratio 2144 (CI_95%: 1343-3424) and 2281 (CI_95%: 1082-4811), respectively.

CONCLUSIONS

The anthropometric and biochemical parameters of Brazilians, especially men, predispose them to greater risks of cardiovascular diseases.