Comparison of low-density lipoprotein cholesterol/high-density lipoprotein cholesterol and total cholesterol/high-density lipoprotein cholesterol for the prediction of thin-cap fibroatheroma determined by intravascular optical coherence tomography

BackgroundThe correlation among the ratios of low-density lipoprotein cholesterol/high-density lipoprotein cholesterol (LDL-C/ HDL-C), total cholesterol/high-density lipoprotein cholesterol (TC/HDL-C) and thin-cap fibroatheroma has not yet been established.MethodsIt was a single center, retrospective observational study. In total, we recruited 421 patients (82.4% men; mean age 65.73 ± 10.44 years) with one culprit vessel which determined by intravascular optical coherence tomography (OCT). The thinnest-capped fibroatheroma (TCFA) group was defined as lipid contents in > 2 quadrants, with the thinnest fibrous cap measuring less than 65 μm. Univariate and multivariate logistic regression were carried out to explore the relationship between lipoprotein ratios, TCFA and other characteristics of plaque. To compare different ratios, the area under curve (AUC) of receiver-operating characteristic (ROC) curve was assessed.ResultsOCT was performed in 421 patients (TCFA group (n = 109), non-TCFA group (n = 312)). LDL-C/HDL-C in the TCFA group was significantly higher than in the non-TCFA group (2.95 ± 1.20 vs. 2.43 ± 0.92, P < 0.05), as was TC/LDL in TCFA and non-TCFA group (4.57 ± 1.58 vs. 4.04 ± 1.13, P < 0.05). Both LDL-C/HDL-C (OR: 1.002 (1.002-1.003), P < 0.05) and TC/HDL-C (OR: 1.001 (1.001-1.004), P < 0.05) were considered independent factors for the prediction of TCFA according to the logistic regression. Based on the AUC comparison, LDL-C/ HDL-C and TC/HDL-C had no significant difference statistically (LDL-C/HDL-C AUC: 0.63; TC/HDL-C AUC: 0.61; P = 0.10) for the prediction of TCFA.ConclusionsLDL-C/HDL-C and TC/HDL-C could be the independent factors for predicting the presence of TCFA, indicating coronary plaque vulnerability in CAD patients. Moreover, TC/HDL-C also showed a comparative performance for the prediction of TCFA as LDL-C/HDL-C.     

Association of the apolipoprotein B/apolipoprotein A-I ratio and low-density lipoprotein cholesterol with insulin resistance in a Chinese population with abdominal obesity

The aim of this study is to assess the relationships among the apolipoprotein B/apolipoprotein A-I ratio (apoB/apoA-I ratio), low-density lipoprotein cholesterol (LDL-C) and insulin resistance (IR) in a Chinese population with abdominal obesity. This is a population-based, cross-sectional study of 3,945 men and 2,141 women with abdominal obesity. Individuals were referred to a primary health service and recruited for analysis. IR was measured using a homeostasis model assessment of insulin resistance (HOMA2-IR) with a HOMA2 calculator. Metabolic syndrome (MetS) was diagnosed using International Diabetes Federation (IDF) criteria. Comparing the apoB/apoA-I ratio and lipid indices using the HOMA2-IR showed that the ratio, LDL-C, total cholesterol level (TC) and triglyceride level (TG) were higher; and the high-density lipoprotein cholesterol level (HDL-C) was lower in the fourth than in the first quartile in both sexes (p????0.001). After adjustment for age, HOMA2-IR was positively correlated with the apoB/apoA-I ratio, LDL-C, TC and TG; and negatively correlated with HDL-C in men (all p?<?0.0001). HOMA2-IR was also positively correlated with the apoB/apoA-I ratio, LDL-C, TC and TG; and negatively correlated with HDL-C in women (all p?<?0.01). After adjustment for age and LDL-C, HOMA2-IR was found to be correlated with the apoB/apoA-I ratio in both men and women (r?=?0.066 and 0.116, p?<?0.0001). After adjustment for age and the apoB/apoA-I ratio, HOMA2-IR was correlated with LDL-C in men and women (r?=?0.063 and 0.044, p?<?0.0001 and p?=?0.0431, respectively). Gender, age, LDL-C, BMI, HOMA2-IR and apoB/apoA-I were the covariates independently associated with presence of the MetS (Odds ratio, OR: 2.183, 1.034, 1.013, 1.157, 1.726 and 1.570, respectively; all p?<?0.05). In conclusion, the study showed that the apoB/apoA-I ratio and LDL-C were positively correlated with IR. Excluding reciprocal interactions, the apoB/apoA-I ratio and LDL-C were still significantly correlated with IR, but the apoB/apoA-I ratio showed a greater correlation with IR than LDL-C in women with abdominal obesity, compared with men with abdominal obesity. Both LDL-C and apoB/apoA-I were independent risk factors of MetS, and the apoB/apoA-I ratio was stronger in this regard than LDL-C for this obese population.     

Low high-density lipoprotein cholesterol is a residual risk factor associated with long-term clinical outcomes in diabetic patients with stable coronary artery disease who achieve optimal control of low-density lipoprotein cholesterol

Diabetes mellitus is recognized an independent risk factor for coronary artery disease (CAD) and mortality. Clinical trials have shown that statins significantly reduce cardiovascular events in diabetic patients. However, residual cardiovascular risk persists despite the achievement of target low-density lipoprotein cholesterol (LDL-C) levels with statin. High-density lipoprotein cholesterol (HDL-C) is an established coronary risk factor that is independent of LDL-C levels. We evaluated the impact of HDL-C on long-term mortality in diabetic patients with stable CAD who achieved optimal LDL-C. We enrolled 438 consecutive diabetic patients who were scheduled for percutaneous coronary intervention between 2004 and 2007 at our institution. We identified 165 patients who achieved target LDL-C <100 mg/dl. Patients were stratified into two groups according to HDL-C levels (low HDL-C group, baseline HDL-C <40 mg/dl; high HDL-C group, ≥40 mg/dl). Major adverse cardiac events (MACE) that included all-cause death, acute coronary syndrome, and target lesion revascularization were evaluated between the two groups. The median follow-up period was 946 days. The rate of MACE was significantly higher in diabetic patients with low-HDL-C who achieved optimal LDL-C (6.9 vs 17.9 %, log-rank P = 0.030). Multivariate Cox regression analysis showed that HDL-C is significantly associated with clinical outcomes (adjusted hazard ratio for MACE 1.33, 95 % confidence interval 1.01–1.75, P = 0.042). Low HDL-C is a residual risk factor that is significantly associated with long-term clinical outcomes among diabetic patients with stable CAD who achieve optimal LDL-C levels.     

血清小而密低密度脂蛋白胆固醇、同型半胱氨酸与颈动脉粥样硬化关系研究

目的探讨血清小而密低密度脂蛋白胆固醇(sdLDL-C),小而密低密度脂蛋白胆固醇与低密度脂蛋白胆固醇之比(sdLDL-C/LDL-C)及同型半胱氨酸(Hcy)与颈动脉硬化的关系,并分析sdLDL-C/LDL-C评价颈动脉斑块的价值。方法选取2017年10月至2019年10月于安徽医科大学合肥第三临床学院心内科住院并行颈动脉彩超检查的200例患者为研究对象,根据颈动脉超声结果分为颈动脉内膜中层厚度(IMT)异常组(n=122)和对照组(n=78)。其中,IMT异常组又分为IMT增厚组(n=30)及颈动脉斑块组(n=92)。Spearman相关分析sdLDL-C与年龄、体质指数(BMI)、LDL-C、高密度脂蛋白胆固醇(HDL-C)、sdLDL-C/LDL-C、超敏C反应蛋白(hs-CRP)、Hcy的相关性;二元Logistic逐步回归方程及有序多分类Logistic回归模型评估颈动脉斑块的独立危险因素。结果IMT异常组血清sdLDL-C、sdLDL-C/LDL-C和Hcy水平均明显高于对照组,差异有统计学意义(P<0.05)。颈动脉斑块组血清sdLDL-C、sdLDL-C/LDL-C和Hcy水平均明显高于IMT增厚组,差异亦均有统计学意义(P<0.001)。Logistic逐步回归分析显示年龄、糖尿病、Hcy、sdLDL-C/LDL-C、sdLDL-C是IMT增厚和颈动脉斑块的独立危险因素。结论在伴有IMT增厚、颈动脉斑块患者中sdLDL-C、sdLDL-C/LDL-C、Hcy水平显著升高。血清sdLDL-C/LDL-C、sdLDL-C、Hcy含量具有颈动脉斑块的预测价值,且是颈动脉粥样硬化的独立危险因素。     

Association between the severity of obstructive sleep apnea and the ratio of low-density lipoprotein cholesterol to high-density lipoprotein cholesterol

The positive association between the ratio of serum low-density lipoprotein cholesterol (LDL-C) to serum high-density lipoprotein cholesterol (HDL-C) and cardiovascular events has recently been receiving much attention. However, the association between the severity of obstructive sleep apnea (OSA) and this ratio has not yet been investigated. Accordingly, we sought to clarify this association and the effect of continuous positive airway pressure (CPAP) therapy on the ratio. We performed polysomnography and LDL-C/HDL-C measurements in 215 patients who were suspected of having OSA. Furthermore, LDL-C/HDL-C was again evaluated 6 months after polysomnography in 30 OSA patients for whom CPAP therapy was initiated and continued, and in 11 age- and sex-matched OSA patients for whom the therapy could not be initiated. The LDL-C/HDL-C correlated positively with apnea-hypopnea index (ρ = 0.28, P < .001) and negatively with the lowest arterial oxyhemoglobin saturation (ρ = -0.30, P < .001). Multivariate regression analysis revealed that ln apnea-hypopnea index (or ln lowest arterial oxyhemoglobin saturation) was independently associated with LDL-C/HDL-C. The LDL-C/HDL-C decreased after 6 months in the CPAP group (2.29 ± 0.67 to 2.11 ± 0.74, P = .02), whereas it did not change in the non-CPAP group (2.65 ± 0.82 to 2.62 ± 0.66, P = .81). The severity of OSA was independently associated with LDL-C/HDL-C, and LDL-C/HDL-C was significantly reduced at 6 months after CPAP therapy. These findings suggest that LDL-C/HDL-C increases in proportion to the severity of OSA, which may contribute partly to an increased risk for cardiovascular events in OSA patients.     

Relation of cholesterol and lipoprotein parameters with carotid artery plaque characteristics: the Atherosclerosis Risk in Communities (ARIC) carotid MRI study

Objective

There is a paucity of data regarding relations of apolipoproteins (apolipoprotein B [ApoB] and apolipoprotein A-1 [Apo A-1]), lipoprotein particle measures (low-density lipoprotein particle concentration [LDLp] and high-density lipoprotein particle concentration [HDLp]), and lipoprotein cholesterol measures (low-density lipoprotein cholesterol [LDL-C], non-high-density lipoprotein cholesterol [non-HDL-C], and high-density lipoprotein cholesterol [HDL-C]) with atherosclerotic plaque burden, plaque eccentricity, and lipid-rich core presence as a marker of high-risk plaques.

Methods

Carotid artery magnetic resonance imaging was performed in 1670 Atherosclerosis Risk in Communities study participants. Vessel wall and lipid cores were measured; normalized wall index (NWI), standard deviation (SD) of wall thickness (measure of plaque eccentricity) were calculated; and lipid cores were detected in vessels with ≥1.5 mm thickness. Fasting concentrations of cholesterol, ApoB and Apo A-1, and LDLp and HDLp were measured.

Results

Measures of plaque burden (carotid wall volume, wall thickness, and NWI) were positively associated with atherogenic cholesterol and lipoproteins (p < 0.05 for total cholesterol, LDL-C, non-HDL-C, ApoB, and LDLp), but not with HDL-C, Apo A-1, or HDLp. SD of wall thickness was associated with total cholesterol (p 0.01) and non-HDL-C (p 0.02). Although measures of atherogenic or anti-atherogenic cholesterol or lipoprotein were not individually associated with detection of a lipid-rich core, their ratios (total cholesterol/HDL-C, non-HDL-C/HDL-C, and LDLp/HDLp) were associated with lipid-rich core presence (p ≤ 0.05).

Conclusion

Extent of carotid atherosclerosis is associated with atherogenic cholesterol and lipoproteins. Atherogenic/anti-atherogenic cholesterol or particle ratios were associated with presence of a detectable lipid-rich core.     

Relation of coronary artery calcium identified by electron beam tomography to serum lipoprotein levels and implications for treatment

This study was designed to determine whether the National Cholesterol Education Program (NCEP) lipid guidelines accurately identify subclinical atherosclerosis and whether low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) levels are related to the extent and prematurity of coronary artery disease (CAD) as determined by electron beam tomography (EBT). Out of personal concern for CAD risk, 930 consecutive asymptomatic subjects, without clinical CAD and on no lipid-lowering agents, underwent EBT. Calcium score and percentile were correlated with total cholesterol (TC), LDL-C, HDL-C, triglycerides, and demographic parameters. A calcium score of > 0 (EBT+) was found in 55% of patients; 45% of patients had a 0 score (EBT-). Mean age (58.0 +/- 10.5 vs 49.3 +/- 9.7 years, p = 0.0001), TC (218 +/- 39 vs 211 +/- 41 mg/dl, p = 0.006), LDL-C (136 +/- 36 vs 127 +/- 27 mg/dl, p = 0.005), and TC/HDL-C (4.6 +/- 1.4 vs 4.2 +/- 1.5, p = 0.0001) were significantly higher and HDL-C (52.2 +/- 17.6 vs 55.4 +/- 19.3 mg/dl, p = 0.008) lower in the EBT+ compared with EBT- group. In the EBT+ group, 75.1% of subjects had LDL-C < 160 mg/dl and would not be advised to use lipid-lowering medications according to NCEP guidelines. In subjects with LDL-C < 160 mg/dl, 51.8% of subjects were EBT+, as were 46.1% of those with LDL-C < 100 mg/dl. There were no significant differences in the calcium scores throughout the entire range of all lipid parameters; calcium percentiles were virtually identical within lipid value subgroups. We conclude that asymptomatic patients with EBT-defined subclinical atherosclerosis are not reliably identified by NCEP guidelines, and TC, LDL-C, HDL-C, TC/HDL-C, and triglyceride levels do not correlate with either the extent or prematurity of calcified plaque burden.     

Non-HDL cholesterol as a predictor of carotid atherosclerosis in the elderly

The aim of the present study was to evaluate sclerotic lesions of the common carotid artery by ultrasonography in 921 in-patients aged 65 years and older (77 +/- 7 years) and investigate whether lipid levels were associated with carotid atherosclerosis. In men, an increased risk for carotid atherosclerosis was associated with increased levels of low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C). Compared to men with the lowest tertile of LDL-C levels (< 83.4 mg/dl), the adjusted odds ratio was 2.502 (95% confidence interval: 1.426-4.390) in those with the middle tertile (83.4-115.2 mg/dl), and 2.688 (1.509-4.790) in those with the highest tertile ( > 115.2 mg/dl). Like the LDL-C level, the non-HDL-C level showed a positive and linear relationship with carotid atherosclerosis. Compared to men with the lowest tertile of non-HDL-C levels ( < 101 mg/dl), the adjusted odds ratio was 2.881 (1.633-5.081) for those with the middle tertile (101-135 mg/dl), and 2.990 (1.651-5.415) for those with the highest tertile ( > 135 mg/dl). Similarly, in women, an increased risk for carotid atherosclerosis was also positively and linearly associated with LDL-C and non-HDL-C. The Non-HDL-C level is a potential predictor of risk for carotid atherosclerosis in the elderly.     

The ratio of plasma high-density lipoprotein cholesterol to total and low-density lipoprotein cholesterol: age-related changes and race and sex differences in selected North American populations. The Lipid Research Clinics Program Prevalence Study

The distribution of the ratios of plasma high-density lipoprotein cholesterol (HDL-C) to total cholesterol (TC) and of HDL-C to low-density lipoprotein cholesterol (LDL-C) are presented for 6900 white and 495 black examinees greater than 4 years old. Measurements were obtained during the visit 2 survey of the Lipid Research Clinics (LRC) Program Prevalence Study, and correspond to a 15% random sample of 60,502 participants screened during the LRC visit 1 survey. Age-specific means, medians, and selected percentiles are given by sex and by gonadal hormone use in white women. Apparent in these cross-sectional data was a consistent age-related decline in the ratio of HDL-C to TC for white male participants, from a mean of 0.360 in the age group 5 to 9 to a mean of 0.211 in the age group 50 to 54. Thereafter the mean ratio increased slightly. In white women not using gonadal hormones the age-related decline in the ratio was only evident starting at the age group 35 to 39, from which it declines from 0.329 to 0.258 in the age group 55 to 59. White women using gonadal hormones showed very minor age-related changes in the HDL-C/TC ratio, varying around a mean of 0.300. The number of blacks examined was low and thus the racial comparisons must be interpreted with caution. For each gender, age-related trends were similar in black and white study participants. Black men, however, had a higher percentage of TC carried as HDL-C than white men in all age groups examined. Black women had a higher percentage of TC in HDL-C than white women only below age 20; in the adult age range no appreciable differences were seen. Pearson correlation coefficients between the lipid, lipoprotein, and lipoprotein ratios are presented. The ratio HDL-C/TC correlated highly with the ratio HDL-C/LDL-C (greater than 0.92 for all groups) and the former may be a more conveniently determined surrogate for the latter. Although not exhaustive regarding the information it conveys about a lipid pattern, the ratio HDL-C/TC has the advantage of summarizing complex associations into a single numerical approximation.     

Effects of Ramadan intermittent fasting on lipid and lipoprotein parameters: An updated meta-analysis

AimsThis systematic review and meta-analysis aimed to clarify several aspects of intermittent fasting during the month of Ramadan on lipid and lipoprotein levels in apparently healthy subjects.Data synthesisWe searched PubMed, Scopus, and Embase databases and the reference lists of previous reviews, up to Feb 2019 for studies that investigated the effects of Ramadan fasting on fasting levels of triglycerides (TG), total cholesterol (TC), HDL-C, LDL-C, and VLDL-C among healthy subjects including pregnant women and athletic subjects. Studies were selected for quality assessment, meta-analyses, subgroup analyses, and meta-regressions; data of 33 eligible studies, conducted between 1978 and 2019, were included in the analysis.ResultsIntermittent fasting showed no significant effect on circulating TG (WMD = ?0.38 mg/dl, 95% CI = ?5.33, 4.57), TC (WMD = ?1.58 mg/dl, 95% CI = ?6.04, 2.88), and LDL-C levels (WMD = 1.85 mg/dl, 95% CI = 0.77, 2.92). Overall, HDL-C (WMD = ?2.97 mg/dl; 95% CI = ?6.43, 0.48 mg/dl) and VLDL-C (WMD = ?1.41 mg/dl; 95% CI = ?2.73, ?0.10 mg/dl) significantly decreased after Ramadan fasting. A significant increase in LDL-C levels was observed in athletic subjects (WMD = 2.97 mg/dl; 95% CI = 0.80, 5.13) and apparently healthy subjects (WMD = 1.81 mg/dl; 95% CI = 0.55, 3.07). Change in TG levels was associated with age (β = ?0.94, P = 0.043), its baseline values (β = ?0.44, P = 0.001), and weight change during the fasting period (β = ?0.57, P = 0.032).ConclusionRamadan fasting may be accompanied by a moderate improvement of lipid and lipoprotein parameters, especially HDL-C levels; fasting appears to be more beneficial for men and athletic subjects.     

Characterization of the effect of serum bilirubin concentrations on coronary endothelial function via measurement of high-sensitivity C-reactive protein and high-density lipoprotein cholesterol

Bilirubin can prevent oxidation of low-density lipoprotein (LDL) and may protect against atherosclerosis and coronary heart disease (CHD). The goal of this study was to characterize the relationship between bilirubin and CHD through measurements of bilirubin concentration, coronary endothelial function, and markers of oxidative stress, inflammation, and lipid/glucose metabolism. The study population consisted of 141 patients without CHD who underwent Doppler flow study. Vascular reactivity was examined by intracoronary administration of papaverine, acetylcholine (ACh) and nitroglycerin using a Doppler guide wire. Serum bilirubin, high-sensitivity C-reactive protein (hsCRP), malondialdehyde-modified LDL, LDL cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), fasting plasma glucose (FPG), and immunoreactive insulin were also measured. Homeostasis model assessment insulin resistance index and estimated glomerular filtration rate (eGFR) were calculated. Univariate analysis revealed that both percent change in coronary blood flow (CBF) and coronary artery diameter induced by ACh correlated positively with log-transformed bilirubin (r = 0.22, P < 0.05; r = 0.20, P < 0.05, respectively). Percent change in CBF in response to ACh correlated positively with eGFR (r = 0.24, P < 0.05) and correlated inversely with age, LDL-C, and log-transformed FPG (r = ?0.24, P < 0.05; r = ?0.17, P < 0.05, r = ?0.22, P < 0.05, respectively). Multivariate analysis revealed that log-transformed bilirubin was the only independent predictor of percent change in CBF in response to ACh. Multivariate analysis revealed that log-transformed hsCRP and HDL-C were independent predictors of log-transformed bilirubin. These results suggest that a high level of bilirubin is associated with favorable coronary endothelial function, which may be mediated via the effect of bilirubin on inflammation and HDL-C.     

Influence of triglyceride concentration on the relationship between lipoprotein cholesterol and apolipoprotein B and A-I levels

A sample of 2,103 men aged 47 to 76 years from the Québec Cardiovascular Study cohort was examined to quantify the influence of plasma triglyceride (TG) levels on the relationship between plasma lipoprotein cholesterol and either apolipoprotein A-I (apo A-I) or apo B concentrations. Regression analyses between high-density lipoprotein cholesterol (HDL-C) and apo A-I through TG tertiles showed highly significant correlations (.62 < or = r < or = .75, P < .0001) in all TG tertiles between these 2 variables. The associations for plasma apo B versus low-density lipoprotein cholesterol (LDL-C) and non-HDL-C levels were also studied on the basis of TG concentrations, and correlation coefficients between either LDL-C or non-HDL-C and apo B were essentially similar among TG tertiles (.78 < or = r < or = .85 and .83 < or = r < or = .86 for LDL-C and non-HDL-C, respectively, P < .0001). Regression analyses also showed that lower HDL-C levels were found for any given apo A-I concentration among men in the 2 upper TG tertiles, whereas lower LDL-C concentrations were observed at any given apo B level among subjects in the upper TG tertile. We further investigated whether there were synergistic alterations in the HDL-C/apo A-I and LDL-C/apo B ratios as a function of increasing plasma TG. A significant association was noted between these 2 ratios (r = .37; P < .0001). Mean HDL-C/apo A-I and LDL-C/apo B ratios were then calculated across quintiles of plasma TG concentrations. Increased TG concentrations were first associated with a reduced HDL-C/apo A-I ratio, followed by a decreased LDL-C/apo B ratio. These results suggest that a relatively modest increase in TG may rapidly alter the relative cholesterol content of HDL particles. Finally, the cholesterol content of the non-HDL fraction appears to be influenced less by TG levels than HDL-C and LDL-C fractions. Thus, the plasma apo B-containing lipoprotein cholesterol level may provide a better index of number of atherogenic particles than the LDL-C concentration, particularly in the presence of hypertriglyceridemia (HTG).     

Small dense low-density lipoprotein cholesterol concentration and carotid atherosclerosis

Low-density lipoprotein cholesterol (LDL-C) and the small dense LDL (SdLDL) phenotype are both predictors for ischemic heart disease. We examined whether cholesterol of SdLDL (SdLDL-C) is more closely associated with carotid artery intima-media thickness (CA-IMT), a surrogate measure of atherosclerosis, than LDL-C and other lipid parameters. The subjects were 326 consecutive participants including those with dyslipidemia, diabetes mellitus, hypertension, chronic kidney disease, and smokers. SdLDL-C was quantified by a newly developed precipitation method, and CA-IMT by high-resolution B-mode ultrasound. In univariate analysis, CA-IMT was most strongly correlated with SdLDL-C (Spearman's r=0.441, P<0.001), followed by apolipoprotein (apo) B, LDL-C, non-high-density lipoprotein cholesterol (Non-HDL-C), and plasma triglycerides (TG). HDL-C and apo A-I correlated inversely with CA-IMT. Non-lipid variables that were associated with CA-IMT were age, sex, presence of diabetes mellitus, presence of hypertension, estimate glomerular filtration rate (eGFR), and C-reactive protein (CRP). Even after adjustment for age, sex, diabetes mellitus, hypertension, smoking, eGFR and CRP, the positive association of CA-IMT with SdLDL-C remained significant, and again stronger than the associations with others lipid parameters. Further analyses revealed that the level of SdLDL-C was elevated in subgroups of the subjects including men, older subjects, smokers, those with higher CRP levels, those with diabetes mellitus, and hypertensive patients. These results indicate that SdLDL-C was the best marker of carotid atherosclerosis among the lipid parameters tested, and suggest that quantitative measurement of SdLDL-C gives useful information in the risk assessment for atherosclerotic disease.     

Risk determination of dyslipidemia in populations characterized by low levels of high-density lipoprotein cholesterol

Background

Current guidelines for managing dyslipidemia qualify patients for treatment based on low-density lipoprotein cholesterol (LDL-C) levels and other risk factors for coronary heart disease (CHD). However, when LDL-C is the sole lipid criterion for initiating therapy, patients with levels below the treatment initiation threshold who are at high risk because of low levels (<40 mg/dL) of high-density lipoprotein cholesterol (HDL-C) might not be identified. Twenty percent of male patients with CHD in the United States fall into this category. The total cholesterol/HDL-C (TC/HDL-C) ratio predicts CHD risk regardless of the absolute LDL-C and HDL-C.

Methods

We compared guidelines based on TC/HDL-C and LDL-C with those recommended by the National Cholesterol Education Program Adult Treatment Panel III (ATP III). Both sets of guidelines were applied to 9837 adults (>20 years of age) in the Turkish Heart Study, which has shown that 75% of men and 50% of women in Turkey have HDL-C <40 mg/dL.

Results

ATP III guidelines identified 14% of Turkish adults, 20 years or older, as candidates for lifestyle treatment only and an additional 18% for drug treatment. In conjunction with ATP III LDL-C thresholds, the TC/HDL-C ratio (>3.5, patients with CHD; ≥6.0, 2+ risk factors, ≥7.0, 0 to 1 risk factor) assigned lifestyle therapy alone to 18% and drug treatment to an additional 36%. Among primary prevention subjects at high risk because of age (men ≥45 years; women ≥55 years), both sets of guidelines prescribed lifestyle therapy for only 5%; however, drug treatment was recommended for an additional 13% by ATP III guidelines and an additional 18% by TC/HDL-C and LDL-C.

Conclusions

In populations at risk for CHD caused by low HDL-C, qualification of subjects for treatment based on either the TC/HDL-C ratio or LDL-C thresholds identifies more high-risk subjects for treatment than LDL-C threshold values alone, and use of the ratio, instead of risk tables, simplifies the approach for physicians.     

Usefulness of lipoprotein ratios in assessing carotid atherosclerosis in Japanese type 2 diabetic patients

ObjectiveIt is indicated that total/HDL cholesterol and LDL/HDL cholesterol ratios have more predictive power for cardiovascular disease compared to classic lipid parameters. However, there have been few reports about the usefulness of these indices for the assessment of early stage atherosclerosis in Japanese type 2 diabetic subjects.MethodsWe examined the relation between various lipid parameters and carotid atherosclerosis in 934 type 2 diabetic subjects without apparent atherosclerotic diseases (males, 71.7%; age, 59.6 ± 10.5 years (mean ± SD)). Serum concentrations of total cholesterol (TC), HDL cholesterol (HDL-C), and triglyceride were measured. LDL cholesterol (LDL-C) level was calculated using the Friedewald formula. The presence of carotid plaque and intima-media thickness (IMT) were evaluated by ultrasonography.ResultsA stepwise multivariate regression analysis demonstrated that HDL-C (β = ?0.110, p < 0.001), TC/HDL-C (β = 0.132, p < 0.001) and LDL-C/HDL-C ratios (β = 0.132, p < 0.001) were independent determinants of IMT even after adjustment of other conventional risk factors. However, there was no significant correlation between IMT and TC, triglyceride, LDL-C, and non-HDL-C levels. TC/HDL-C and LDL-C/HDL-C ratios and non-HDL-C levels were significantly higher, but HDL-C levels were significantly lower in patients with carotid plaque than those without it (p < 0.05). There was no significant difference between the groups regarding TC, LDL-C, and triglyceride levels. Furthermore, TC/HDL-C (OR; 1.34, p < 0.001) and LDL-C/HDL-C (OR; 1.54, p < 0.001) ratios showed a positive and linear relationship with the prevalence of carotid plaque, whether covariates were adjusted or not.ConclusionsTC/HDL-C and LDL-C/HDL-C ratios are useful as a tool to assess the risk of early stage atherosclerosis in Japanese type 2 diabetic patients.     

Total cholesterol/HDL cholesterol ratio vs LDL cholesterol/HDL cholesterol ratio as indices of ischemic heart disease risk in men: the Quebec Cardiovascular Study.

BACKGROUND: Total cholesterol (TC)/high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C)/HDL-C ratios are used to predict ischemic heart disease risk. There is, however, no consensus on which of these 2 indices is superior. The objective of the present study was to present evidence that the LDL-C/HDL-C ratio may underestimate ischemic heart disease risk in overweight hyperinsulinemic patients with high triglyceride (TG)-low HDL-C dyslipidemia. METHODS: A total of 2103 middle-aged men in whom measurements of the metabolic profile were performed in the fasting state were recruited from 7 suburbs of the Quebec metropolitan area. RESULTS: The relationship of LDL-C/HDL-C to TC/HDL-C ratios was examined among men in the Quebec Cardiovascular Study classified into tertiles of fasting TG levels. For any given LDL-C/HDL-C ratio, the TC/HDL-C ratio was higher among men in the top TG tertile (>168 mg/dL [>1.9 mmol/L]) than in men in the first and second TG tertiles. Adjustment of the TC/HDL-C ratio for LDL-C/HDL-C by covariance analysis generated significant differences in average TC/HDL-C ratios among TG tertiles (P<.001). Greater differences in features of the insulin resistance syndrome (insulinemia, apolipoprotein B, and LDL size) were noted across tertiles of the TC/HDL-C ratio than tertiles of the LDL-C/HDL-C ratio. CONCLUSION: Variation in the TC/HDL-C ratio may be associated with more substantial alterations in metabolic indices predictive of ischemic heart disease risk and related to the insulin resistance syndrome than variation in the LDL-C/HDL-C ratio.     

中老年人群血脂水平对新发颈动脉斑块的预测作用

目的 了解2002年至2007年中老年人群颈动脉斑块的变化情况,评价基线血脂水平对新发颈动脉斑块的预测作用.方法 研究样本来自中美队列中的石景山人群和多省市队列中的北京大学社区人群.2002年9月对这两个人群进行基线颈动脉超声检查和心血管病危险因素调查,2007年9至10月复查颈动脉超声.以两次颈动脉检查数据完整的2000名中老年人为研究对象,对基线血脂水平与颈动脉斑块的关系进行分析.结果 (1)2002年至2007年,颈动脉斑块患病率男性从30.3%增加到62.2%,女性从21.5%增加到51.5%;新发斑块率男性为41.8%,女性为34.1%.(2)男女两性颈动脉新发斑块率随着基线总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、非高密度脂蛋白胆固醇(non-HDL-C)及总胆固醇与HDL-C比值(TC/HDL-C)水平的增高而增加,其变化趋势差异均有统计学意义(P＜0.05或P＜0.01).(3)交叉分析显示,LDL-C,HDL-C,甘油三酯对斑块发生率有协同作用.(4)多因素分析显示,高LDL-C、高non-HDL-C和高TC/HDL-C是男女两性新发颈动脉斑块的独立影响因素(男性OR值分别为1.44、1.45、1.59,女性OR值分别为1.47、1.35、1.64,均P＜0.05).结论 2002年至2007年,中老年人群颈动脉斑块患病率在快速增长.高LDL-C、nonHDL-C和TC/HDL-C水平是中老年人群新发颈动脉斑块的独立预测指标.     

Longitudinal and secular trends in lipoprotein cholesterol measurements in a general population sample. The Framingham Offspring Study

Two fasting lipoprotein cholesterol measurements have been made on Framingham Offspring Study participants, first in 1971-75 and again in 1979-83. Longitudinal analysis (n = 2433, age 20-49 at first exam) using multivariate regression found aging, weight gain, vasectomy, menopause, and increased smoking are associated with worsening lipoprotein profiles, while increased alcohol consumption is associated with increased high density lipoprotein cholesterol (HDL-C). Average increases in low density lipoprotein cholesterol (LDL-C) and very low density lipoprotein cholesterol (VLDL-C) in women accelerate with age; in men the increases are similar or perhaps decelerate with age. Secular trends were measured using age-adjusted mean values for individuals aged 25-54. Averages of total cholesterol, LDL-C (men only), systolic and diastolic blood pressure, body mass index, number of cigarettes per day, and alcohol consumption were lower at the second examination. Two secular trends in women indicate a possible worsening of population lipoprotein profiles: mean VLDL-C was higher and mean HDL-C lower at the second exam.     

A comparison of HDL and LDL cholesterol for prevalent coronary calcification

BACKGROUND: Coronary calcification is a marker for coronary atherosclerosis. It has been postulated that high levels of high density lipoprotein cholesterol (HDL-C) are associated with a reduced amount of atherosclerotic disease while previous reports have found a lack of association between low density lipoprotein cholesterol (LDL-C) and coronary calcification (CAC). The purpose of this study was to compare the correlation and predictive power of HDL-C with LDL-C for prevalent coronary calcification. METHODS: A total of 6093 subjects were studied with respect to coronary calcification, serum cholesterol indices, personal health history and body morphology. Analyses consisted of correlation coefficients, logistic regression and sensitivity analysis to determine the strength of association between HDL-C and coronary calcification after controlling for covariates. RESULTS: The correlation between HDL-C and coronary calcium score (CCS) was three times that of LDL-C. Individuals with an HDL-C level <40 mg/dl had significantly higher calcium scores while increases in HDL-C were associated with a significant reduction in risk for the presence of any calcified plaque. Results of multivariate logistic regression revealed that HDL-C is predictive of calcified plaque development independent of LDL-C. Sensitivities and positive predictive values for both HDL-C and LDL-C were low. CONCLUSIONS: Increasing levels of HDL-C were associated with less coronary calcification and a smaller probability of having any calcified disease supporting the antiatherogenic hypothesis for HDL-C. HDL-C predicts the presence of any calcified atherosclerotic plaque independently of LDL-C. However, neither parameter seems suitable as a screening tool for predicting prevalent calcified atheromatous disease.     

Plasma fasting and nonfasting triglycerides and high-density lipoprotein cholesterol in atherosclerotic stroke: Different profiles according to low-density lipoprotein cholesterol

Although low-density lipoprotein cholesterol (LDL-C) is the main lipid target for cardiovascular risk reduction, recent studies suggest that other lipid indicies are also associated with vascular events. We hypothesized that the association of triglycerides (TG) and high-density lipoprotein cholesterol (HDL-C) with atherosclerotic stroke (AS) differs depending on LDL-C levels. Data prospectively collected on subjects admitted with acute ischemic stroke to a university medical center were analyzed. We divided the patients into AS and non-atherosclerotic stroke (NAS) groups and independent association of lipid parameters and genetic influences of apolipoprotein A5 (ApoA5) polymorphisms with AS were evaluated. Of 268 patients, 160 (59.7%) were classified with AS and 108 (40.3%) were classified with NAS. Vascular risk factors were more prevalent in AS patients than in those with NAS; additionally, AS patients' anthropometric indexes and laboratory findings showed that they were prone to atherosclerosis. AS was independently associated with fasting TG (OR per 10 mg/dL increase, 1.38; 95% CI, 1.16–1.64; OR for highest vs. lowest tertile, 12.85; 95% CI, 3.31–49.85), HDL-C (OR per 10 mg/dL increase, 0.61; 95% CI, 0.42–0.88; OR for lowest vs. highest tertile, 4.28; 95% CI, 1.16–15.86), and nonfasting TG (OR per 10 10 mg/dL increase, 1.25; 95% CI, 1.11–1.42; OR for highest vs. lowest tertile, 8.20; 95% CI, 1.98–33.88) only among patients with LDL <100 mg/dL. No interaction was observed between fasting and nonfasting TG and ApoA5 polymorphisms. In conclusion, fasting and nonfasting TG and HDL-C were associated with AS only when patients had low levels of LDL-C. Non-LDL-C may have an additional role in addition to the LDL-C levels in AS development.