Low density lipoprotein cholesterol, lipoprotein(a), and apo(a) isoforms in the elderly: relationship to fasting insulin. Associazione Medica Sabin

BACKGROUND AND AIM: Insulin resistance/hyperinsulinemia are often associated with aging and could play an important role in the development of glucose intolerance and dyslipidemia in the elderly. We investigated the relationship between plasma fasting insulin with total cholesterol (TC) and low density lipoprotein LDL cholesterol (LDL-C), triglycerides (TG), lipoprotein(a) [Lp(a)] levels apolipoprotein (a) [apo (a)] isoforms in 100 free-living "healthy" octo-nonagenarians. METHODS AND RESULTS: Fasting insulin was positively correlated with TG, whereas a negative relation was found with TC and LDL-C (r = -0.29 and r = -0.28 respectively; p < 0.01), LDL-C/apo B, HDL-C and apo A-I levels. Fasting insulin was also inversely correlated with Lp(a) levels (r = -0.22; p < 0.03), whereas the latter were significantly related with TC and LDL-C (r = 0.30 and r = 0.31; p < 0.005), TG (r = 0.21; p < 0.05) and apo B (r = 0.26; p < 0.02). There was a negative relation between Lp(a) levels and apo(a) isoforms: the greater the apo(a) molecular weight, the lower the Lp(a) level (p < 0.0001). Fasting insulin increased with apo(a) size, though the difference in insulin levels among apo(a) isoforms was not significant (p = 0.4). Multiple regression analysis showed that fasting insulin was the best predictor of LDL-C (R2 = 0.14; p = 0.002) irrespective of age, gender, BMI, waist circumference and TG, while apo(a) isoform size, BMI and waist circumference were related with Lp(a) irrespective of TC and LDL-C, TG and apo B (R2 = 0.35 to 0.37; p < 0.0001). CONCLUSIONS: These results suggest that fasting insulin levels significantly influence LDL-C metabolism in old age. Lp(a) levels seem to be very strongly related to genetic background, although an indirect relation with insulin through adiposity and/or other associated lipid abnormalities cannot be ruled out.     

Dyslipoproteinemia in patients with active rheumatoid arthritis: effects of disease activity, sex, and menopausal status on lipid profiles

OBJECTIVE: To investigate the lipid profiles in patients with active rheumatoid arthritis (RA) and to assess the relationship of inflammatory disease activity markers, sex, and menopausal status with lipid profiles. METHODS: Three groups of patients with active RA (n = 184) were studied: men (n = 61, mean age 50.8 +/- 4.81 yrs), premenopausal women (n = 58, mean age 39.2 +/- 2.44 yrs), and postmenopausal women (n = 65, mean age 60.4 +/- 2.14 yrs), and healthy controls (n = 161): men (n = 65, mean age 50.9 +/- 3.42 yrs), premenopausal women (n = 47, mean age 40.3 +/- 1.66 yrs), and postmenopausal women (n = 49, mean age 61.3 +/- 3.16 yrs). We measured fasting plasma levels of total cholesterol (TC), triglyceride (TG), HDL-cholesterol (HDL-C), LDL-cholesterol (LDL-C), lipoprotein (a) [LP(a)], apolipoprotein A1 (apo A1), apolipoprotein B (apo B), and erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). RESULTS: Male RA patients had significantly higher apo B/apo A1 and LP(a) and lower HDL-C than male controls. Female RA patients had significantly higher TC, LDL-C, and LP(a) than female controls. Premenopausal RA patients had significantly higher LDL-C, TC/HDL-C, LDL-C/HDL-C, and apo B/apo A1 and lower TG and HDL-C than premenopausal controls. Postmenopausal RA women had significantly higher TG and LP(a) and lower TC than postmenopausal controls. Female RA patients had higher HDL-C, apo A1, and TC/HDL-C and lower apo B/apo A1 than male RA patients. Postmenopausal RA patients had significantly higher TC, TG, TC/HDL-C, apo B, LP(a), and LDL-C/HDL-C than premenopausal RA patients. CRP correlated positively with TC/HDL-C, LDL-C/HDL-C, and apo B/apo A1 and negatively with HDL-C in male RA patients. In female RA patients CRP had positive correlation with TC/HDL-C and LDL-C/HDL-C and negative correlation with HDL-C. CONCLUSION: These findings suggest that patients with active RA have altered lipid profiles and that disease activity, sex, and menopausal status affect lipid profiles, and these would be expected to change the pattern of atherosclerotic events in RA.     

Risk factors for cardiovascular disease in women with subclinical hypothyroidism.

Overt hypothyroidism may result in accelerated atherosclerosis and coronary heart disease (CHD) presumably because of the associated hypertension, hypercholesterolemia, and hyperhomocysteinemia. As many as 10%-15% of older women have subclinical hypothyroidism (SH) and thyroid autoimmunity. Whether SH is associated with risk for CHD is controversial. We examined 57 women with SH and 34 healthy controls. SH was defined as an elevated thyrotropin (TSH) (>4.5 mU/L) and normal free thyroxine (FT(4)) level (8.7-22.6 nmol/L). None of the patients had been previously treated with thyroxine. In all participants we determined blood pressure, body mass index (BMI), and fasting TSH, FT(4), antibodies to thyroid peroxidase and thyroglobulin, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides, folic acid, vitamin B(12), creatinine, and total plasma homocysteine levels. The SH and control groups did not differ in their total homocysteine values. Mean diastolic blood pressure was increased in SH patients versus controls (82 vs. 75 mm Hg; p < 0.01). Mean values of TC, HDL-C, LDL-C, triglycerides, TC/HDL-C, and LDL-C/HDL-C were not different in patients with SH compared with controls. Individual analysis revealed that the percentage of patients with SH having hypertension (20%), hypertriglyceridemia (26.9%), elevated TC/HDL-C (11.5%), and LDL-C/HDL-C (4%) ratios were higher than the percentages in controls. Hyperhomocysteinemia (> or = 10.98 micromol/L) was observed in 29.4% of SH and was not significantly different from the percentage in controls (21.4%). No significant correlation between TSH and biochemical parameters was detected. We conclude that subclinical hypothyroidism in middle-aged women is associated with hypertension, hypertriglyceridemia, and elevated TC/HDL-C ratio. This may increase the risk of accelerated atherosclerosis and premature coronary artery disease in some patients.     

Association between plasma lipids, and apolipoproteins and coronary artery disease: a cross-sectional study in a low-risk Korean population

BACKGROUND: Due to the lower level of the traditional lipid profiles in Koreans than in the series of patients from the western countries, the need to investigate other lipid parameters to help identify the individuals at high risk of CAD has been emphasized. AIM AND METHODS: To investigate whether apolipoprotein B (apo B), apolipoprotein A-I (apo A-I) and their ratio give additional information to the traditional lipid risk factors for discriminating the individuals at high-risk for coronary artery disease (CAD), 544 subjects, who met the lipid criteria of total cholesterol (TC) <230 mg/dl, low-density lipoprotein cholesterol (LDL-C) <120 mg/dl and high-density lipoprotein cholesterol (HDL-C) >40 mg/dl were recruited. Patients were considered to be CAD(+) if they had > or =50% stenosis in at least one coronary artery. RESULTS: In men, TC and apo B/apo A-I ratio were significantly different between groups with and without CAD after adjusting for age and diabetes (P = 0.037 and 0.035), and in women, triglyceride (TG), HDL-C and apo B/apo A-I ratio were significantly different after adjusting for age, diabetes and smoking status (P = 0.006, 0.007 and 0.030, respectively). In the lowest quartile of TC, TG and LDL-C, and the highest quartile of HDL-C, only apo B/apo A-I ratio was associated with CAD in both men and women. The only variable showing a significant difference between patients with and without CAD was apo B/apo A-I ratio. In models assessing whether apolipoproteins give additional information to traditional lipid risk factors, HDL-C, LDL-C, apo B/apo A-I ratio and in women but not in men, TG and apo B were all independent markers for the presence of CAD. Among the nontraditional lipid factors, only apo B/apo A-I ratio showed its additional value for identifying the presence of CAD. CONCLUSION: Apo B/apo A-I ratio is the only variable that differentiates the patients with CAD from those without and, furthermore, gives additional information to that supplied by traditional lipid risk factors in a low-risk Korean population.     

Relation of the -514C/T polymorphism in the hepatic lipase gene to serum HDL and LDL cholesterol levels in postmenopausal women under hormone replacement therapy

Hepatic lipase (HL) is a lipolytic enzyme that catalyzes hydrolysis of triglycerides and phospholipids in all major classes of lipoproteins. Recently, a -514C/T polymorphism in the promoter region of the HL gene was found to be associated with variations in hepatic lipase activity and serum high density lipoprotein cholesterol (HDL-C) levels. Postmenopausal hormone replacement therapy (HRT) has known favorable effects on serum lipid and lipoprotein levels. In this study, we examined the relation between the -514C/T polymorphism and serum lipid and lipoprotein levels in postmenopausal women prior to and after 3 months of HRT. Significant associations between the -514 C/T polymorphism and HDL-C, low density lipoprotein cholesterol (LDL-C) and apolipoprotein A-I (apo A-I) levels were observed before and/or after 3 months of HRT. With HRT, serum total cholesterol (TC), LDL-C and apolipoprotein B (apo B) levels were reduced significantly (P=0.0001), and HDL-C and apo A-I levels were increased significantly (P=0.0001). However, the degrees of change in lipid and lipoprotein levels due to HRT did not differ significantly between the HL genotypes.     

The rebound of lipoproteins after LDL-apheresis. Kinetics and estimation of mean lipoprotein levels

We studied the rebound of lipoproteins in 20 hypercholesterolemic men [mean total cholesterol (TC) levels 9.6+/-1.8 mmol/l] after LDL-apheresis (LA) to determine the rate of recovery and the change in cholesterol synthesis, and to find a uniform estimation for time-averaged levels. After 10-20 months on biweekly LA using dextran sulfate cellulose columns and concomitant simvastatin administration, time-averaged levels (+/-SD) measured by integration of the area under the curve were as follows: TC 4.4+/-1.0 mmol/l, LDL cholesterol (LDL-C) 2.5+/-1.0 mmol/l, apolipoprotein B (apo B) 1. 3+/-0.3 g/l, triglycerides (TG) 1.7+/-0.7 mmol/l, HDL-C 1.1+/-0.2 mmol/l, and lipoprotein(a) [Lp(a)] 53.7+/-49.4 mg/dl. Mean acute reductions in TC, LDL-C, apo B, Lp(a), and TG were 61, 77, 75, 76, and 62%, respectively. HDL-C levels were not influenced. Median recovery half times for TC, LDL-C, apo B, and Lp(a) were 3.0, 4.0, 2. 3, and 3.5 days, respectively. The rebound of Lp(a) was identical to LDL-C, in 12 and 13 days post-treatment, respectively, whereas apo B and TC returned to pre-treatment levels in 7.5 and 10 days, respectively, due to the fast rebound of VLDL particles. Notwithstanding these differences, time-averaged levels (C(AVG)) could be estimated uniformly for the four latter parameters with the formula: C(AVG)=C(MIN)+0.73(C(MAX)-C(MIN)), where C(MAX) and C(MIN) are the immediate pre- and post-treatment levels. During long-term treatment the whole-body cholesterol synthesis was increased as measured by the ratio lathosterol to cholesterol of 3.24+/-1.49 mmol/mmol, whereas no further transient increase in the recovery period after LA was found. In conclusion, long-term LA and simvastatin therapy induced acute and chronic changes in lipids and lipoproteins showing the feasibility of biweekly treatment. It was shown that time-averaged levels, as a measure for the effective plasma levels, can be accurately estimated from pre- and post-treatment levels only.     

女性原发性高血压患者绝经前后脂蛋白(a)及血脂水平变化的研究

目的　观察女性原发性高血压患者绝经前后脂蛋白 (a) [L p(a) ]及血脂水平的变化 ,探讨其对女性冠心病发病情况可能存在的影响。方法　女性原发性高血压患者 12 1例 ,测定 L p(a)、总胆固醇 (TC)、三酰甘油 (TG)、低密度脂蛋白胆固醇 (L DL- C)和高密度脂蛋白胆固醇 (HDL- C)。对比绝经前后 L p(a)及血脂水平的变化 ,并与女性健康体检者 (对照组 )进行对比。结果　高血压组 L p(a)、TC、TG、L DL - C均显著高于对照组 ,而 HDL - C及 HDL - C/TC则明显低于对照组 ,在所有原发性高血压患者中 ,绝经后的患者 L p(a)、TC、TG、L DL - C显著高于绝经前患者 ,而 HDL - C/ TC则前者低于后者。结论　绝经后原发性高血压患者 L p(a)、TC、L DL - C均明显高于绝经前患者 ,而HDL- C/ TC则低于绝经前患者 ,提示绝经后女性原发性高血压患者 L p(a)及血脂水平增高与内源性雌激素水平下降有关 ,是绝经后冠心病发病率明显上升的重要原因。     

Effects of age and cigarette smoking on serum concentrations of lipids and apolipoproteins in a male military population

The effects of age and cigarette smoking on lipids and apolipoproteins were studied in men, 20-65 years old, randomly selected from a military population in the Madrid area, Spain. Subjects were classified as non-smokers, medium smokers (10-20 cigarettes/day) and heavy smokers (more than 20 cigarettes/day). Smoking prevalence was 58%. Serum apolipoprotein A-I and HDL-cholesterol (HDL-C) were not age-dependent, while total cholesterol (TC), triglycerides (TG), LDL-cholesterol (LDL-C) and the TC/HDL-C ratio increased with age. None of the variables studied was age-dependent over 30 years. The effects of smoking on TC, TG, LDL-C, HDL-C, TC/HDL-C ratio, apolipoprotein A-I, apolipoprotein B, and apo A-I/apo B ratio in the 20-29-year-old group appeared to be prominent in heavy smokers (P values less than 0.001, less than 0.05, less than 0.01, less than 0.05, less than 0.001, less than 0.05, less than 0.01 and less than 0.05, respectively) but not in medium smokers, in which only TG increased significantly (P less than 0.001). Few differences were noted between non-smokers and smokers over 30 although the TC/HDL-C ratio did increase in heavy smokers (P less than 0.05).     

Impaired plasma viscosity via increased cholesterol levels in peripheral occlusive arterial disease [correction of disase

The aim of this study was to investigate the relationship between plasma viscosity and lipoprotein and apolipoprotein pattern in normo- and hypercholesterolemic patients with peripheral occlusive arterial disease (POAD). 40 patients with POAD have been selected (8 females and 32 males, mean age: 54+/-3.2 years) with clinically evident superficial femoral occlusive artery disease. They were separated into two groups as normocholesterolemic (plasma total cholesterol <200 mg/dl) and hypercholesterolemic (plasma total cholesterol >200 mg/dl). Plasma total cholesterol, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglycerides, total protein, and albumin levels were determined by enzymatic methods using commercial kits. Levels of apolipoprotein AI (apo AI), and apolipoprotein B (apo B) were measured using a immunoturbidometric method. Plasma viscosity (PV) was measured by capillary viscometer. Classifying the patients with PAOD according to the cholesterol levels; hypercholesterolemic (mean total-cholesterol: 227.90+/-26.97 mg/dl) patients had significantly higher LDL-C, PV and triglyceride levels compared with nornocholesterolemic patients (p<0.001, p<0.001, p<0.001, respectively). HDL-C and apo B were significantly lower in hypercholesterolemic patients than in normocholesterolemic patients (p<0.001, p<0.001, respectively). PV was positively correlated with total cholesterol (r=0.485, p<0.05), atherogenic index (r=0.624, p<0.01), total-C/HDL-C ratio (r=0.624, p<0.05), and LDL-C/HDL-C ratio (r=0.707, p<0.001) in hypercholesterolemic patients with POAD. PV was higher in hypercholesterolemic patients with POAD than in normocholesterolemic patients with POAD. We suggest that POAD patients should be regarded as a heterogenous group with lipid and lipoprotein parameters in order to assess the microcirculation in the affected limb. In case of dyslipidemia in POAD patients an elevated plasma viscosity should be considered as coexisting risk factor.     

Effects of menopause and obesity on lipid profiles in middle-aged Taiwanese women: the Chin-Shan Community Cardiovascular Cohort Study

In this cross-sectional study, we examined the associations between lipid profiles and menopausal status, age, and obesity in Taiwanese women. The study population, established in 1990-91, consisted of 671 premenopausal and 872 postmenopausal women from the Chin-Shan Community Cardiovascular Cohort (CCCC). The associations of age, body mass index (BMI), and menopausal status with serum levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), apoproteins (Apo) A-1 and B, and lipoprotein (a) [Lp (a)] were evaluated. The results showed that menopause was associated with significant increases in TC, LDL-C, TG, and Apo B levels (all P < 0.001). Total cholesterol, LDL-C, TG, and Apo B levels increased consistently with BMI in middle-aged women, regardless of menopausal status. Among women aged 45-49, menopausal women had significantly higher levels of TC and LDL-C than premenopausal women (P < 0.01). However, TG and Apo B levels were higher in postmenopausal than in premenopausal women aged 50-54 years (P < 0.05). Standardized regression analyses showed all lipid variables, except those of Apo A1 and Lp (a) before menopause and TC, LDL-C, and Lp (a) after menopause, were significantly associated with BMI (all P < 0.01). We conclude serum lipid levels in Taiwanese women are no more strongly associated with menopause and BMI than with age.     

Subcutaneous central fat is associated with cardiovascular risk factors in men independently of total fatness and fitness

The purpose of this study was to analyze the single and independent associations of whole body composition and fat distribution with cardiovascular disease (CVD) risk factors and fitness in middle-aged men. Sixty-two healthy Caucasian men (37.6 +/- 2.9 yr, 81.8 +/- 11.3 kg, 171.5 +/- 4.9 cm) participated in the study. Dual-energy x-ray absorptiometry (DXA) was used to assess total and regional body composition. The triceps, biceps, midthigh, calf, subscapular, chest, abdominal and suprailiac skinfolds, and the waist, hip and midthigh circumferences, and sagittal diameter were estimated. Cardiovascular fitness was estimated with a submaximal test. Bivariate and partial correlation analysis were used to study the association of total body percent fat (%fat), DXA trunk fat and trunk skinfolds (sum of subscapular, chest, abdominal, and suprailiac) and fitness with insulin, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), TC/HDL-C, low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), apolipoprotein AI (apo AI), apolipoprotein B (apo B), lipoprotein(a) [Lp(a)], and diastolic and systolic blood pressure. All anthropometric and DXA body composition variables were significantly correlated with TC/HDL-C (from .26 to .50, P < .05). Similar relationships were found for insulin, HDL-C, and systolic blood pressure (r from .26 to .47, P < .05). Cardiovascular fitness was significantly (P < .05) associated with insulin (r = -.36), HDL-C (r = .27), TC/HDL (r = -.27), and with systolic blood pressure (r = -.37). After controlling for trunk skinfolds, none of the anthropometric and DXA body composition variables were correlated with any of the CVD risk factors. Similarly, when controlling for trunk skinfolds, cardiovascular fitness was not related to any of the metabolic variables. After adjusting for %fat, DXA trunk fat, and cardiovascular fitness, trunk skinfolds remained significantly (P < .05) related to insulin (r = .35), HDL-C (r = -.40), TC/HDL-C (r = .43), and apo AI (r = -.39). In conclusion, this study suggests that subcutaneous truncal fat, as estimated by skinfolds, is an independent predictor of CVD risk factors, and that the association between cardiovascular fitness and these risk factors may be mediated by the levels of abdominal subcutaneous fat in Caucasian middle-aged men.     

Lipid profile of children with a family history of coronary heart disease or hyperlipidemia: 9-year experience of an outpatient clinic for the prevention of cardiovascular diseases

The authors evaluated the lipid profile of children with a positive family history of coronary heart disease (CHD), cerebrovascular disease (CVD), or hyperlipidemia and compared them with controls in order to identify risk indicators for atherosclerosis. A group of 315 children (group A) aged more than 2 years old with a positive family history were evaluated for serum concentrations of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), apolipoprotein B100 (ApoB100), apolipoprotein A1 (Apo A1), and lipoprotein (a) (Lp[a]). These values were compared with the levels of a control group of 214 children of comparable age (group B). The median age of children in groups A and B was 10.6 (range 2.3-16) and 9.8 (range 3-13.7) years of age, respectively. Among these children, 196 (52%), 47 (12.5%), and 72 (19.1%) had a positive family history of CHD (group A1), cerebrovascular disease (CVD) (group A2), and hypercholesterolemia (group A3), respectively. We identified 8 children with genetically determined dyslipidemia: 2 children with homozygous and 6 with heterozygous familial hypercholesterolemia. Children in group A3 had significantly higher concentrations of TC, TG, LDL-C, and ApoB100 and lower concentrations of Apo A1 compared with controls, while no significant differences were found in concentrations of lipid variables among children of group A1, A2, and A3. Significant differences were also noted in the concentrations of TC, LDL-C, and Lp(a) between children of group A1 and controls. Screening the progeny of young patients with CHD or familial hypercholesterolemia can identify children at excessive risk for future vascular disease.     

Increased serum lipids are associated with higher CD4 lymphocyte count in HIV-infected women

OBJECTIVE: Highly active antiretroviral therapy (HAART) has been associated with dyslipidaemia; however, the roles of immune status and non-HIV-disease risk factors remain unclear. METHODS: A cross-sectional analysis of fasting lipids was carried out for 231 women, of whom 132 were HIV-infected and 99 were uninfected. The concentrations of total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides, and apolipoprotein B (apo B) were measured. CD4 lymphocyte count, hepatitis C status, demographics, diet, and anthropometrics were also assessed. RESULTS: A total of 132 women were HIV-infected [30 were antiretroviral-naive, 68 were on protease inhibitors (PIs), and 34 were on non-PI HAART]. HIV infection was associated with higher triglycerides, lower HDL-C, and, among obese women, higher total cholesterol and LDL-C. Non-PI and PI HAART were each independently associated with higher total cholesterol, LDL-C, and apo B, compared with being ART-naive. Among HIV-infected women, after adjustment for HAART use, women with a CD4 lymphocyte count > or =500 cells/microL had total cholesterol 41.8 mg/dL (P = 0.002) and LDL-C 28.8 mg/dL (P = 0.01) higher, on average, than women with a CD4 count <200 cells/microL. Women with a CD4 count of 200-499 cells/microL had total cholesterol 26.31 mg/dL higher, on average, than those with a CD4 count <200 cells/microL (P = 0.04), although differences in LDL-C did not reach significance (15.51 mg/dL; P = 0.12). A higher CD4 count was also associated with higher apo B (P < 0.001). Active hepatitis C infection was associated with lower total cholesterol, LDL-C, triglycerides, and apo B. CONCLUSIONS: Higher CD4 lymphocyte counts were associated with higher lipid levels, suggesting that immune competence may independently affect the dyslipidaemia seen in the HAART era. In addition, it is important that hepatitis C status be assessed in studies of dyslipidaemia in the HIV-infected population.     

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).     

老年冠心病患者血清脂质和脂质过氧化物测定的临床意义

本文观测了４４例老年冠心病患者血清脂质，丙二醛和超氧化物歧化酶，并与健康老年人对照比较，结果显示除胆固醇外其余各项指标２组间均有显著差异，老年ＣＨＤ组ＭＤＡ明显高于对照组，而ＳＯＤ则与之相反。多元回归分析表明，血清低密度脂蛋白胆固醇，而血清高密度脂蛋白胆固醇与ＳＯＤ呈显著正相关。提示老年ＣＨＤ患者高脂血症与脂质过氧化间有一定关系，它对判断老年ＣＨＤ的病情及预后有重要参考意义。     

Adiponectin is independently associated with apolipoprotein B to A-1 ratio in Koreans

Apolipoprotein B to A-1 (apo B/A-1) ratio is reportedly a better predictor of atherosclerotic vascular disease than low-density lipoprotein cholesterol (LDL-C). The aim of this study was to assess the association of serum apo B/A-1 ratio with insulin resistance and adiponectin in patients with different grades of glucose intolerance. Patients were divided according to glucose tolerance into 3 groups: normal glucose tolerance without metabolic syndrome (n = 229), impaired fasting glucose (subjects with fasting plasma glucose level between 100 and 125 mg/dL, n = 658), and type 2 diabetes mellitus (n = 381). Serum concentrations of apo B, apo A-1, glucose, total cholesterol (TC), triglycerides, and high-density lipoprotein cholesterol (HDL-C) and adiponectin were measured. Insulin resistance was estimated by the homeostasis model assessment of insulin resistance index (HOMA-IR). There were significant differences in metabolic parameters among the groups, including waist circumference, insulin, HOMA-IR, and apo B/A-1 ratio, which increased sequentially with glucose intolerance, whereas adiponectin level decreased with increasing severity of glucose intolerance. The apo B/A-1 ratio was significantly correlated with TC, triglycerides, LDL-C, HDL-C, adiponectin, and HOMA-IR in normal glucose tolerance, impaired fasting glucose, and type 2 diabetes mellitus. Multiple regression analysis showed that apo B/A-1 ratio was significantly associated with TC, LDL-C, HDL-C, and adiponectin. In conclusion, apo B/A-1 ratio was significantly associated with insulin resistance according to glucose intolerance; and serum adiponectin was an important independent factor associated with apo B/A-1 ratio in Koreans.     

原发性高血压患者合并血脂异常与血浆胰岛素浓度的关系

目的　探讨原发性高血压患者血浆胰岛素浓度与血脂、脂蛋白及载脂蛋白水平的关系。方法　比较高血压组与对照组及高血压患者按胰岛素水平分组后与对照组的总胆固醇 (TC)、三酰甘油 (TG)、高密度脂蛋白胆固醇(HDL- C)、低密度脂蛋白胆固醇 (L DL- C)、载脂蛋白 AI(apo AI)、载脂蛋白 B(apo B)和血浆胰岛素的水平。结果　原发性高血压患者血脂成分及胰岛素水平均较对照组有明显差异 (分别 P<0 .0 1和 P<0 .0 5 )。按胰岛素水平分组 ,A组胰岛素浓度 <15 ml U / L ,B组胰岛素浓度≥ 15 m IU / L而 <2 5 ml U / L和 C组胰岛素浓度≥ 2 5 m l U /L ;各组与对照组比 ,高血压患者 TC、TG、L DL - C、apo B明显升高 (分别 P<0 .0 1和 P<0 .0 5 ) ,HDL - C、apo AI显著降低 (P<0 .0 1)。高血压患者 TG浓度随胰岛素水平增高而明显增加。结论　原发性高血压患者血浆胰岛素水平增加是其脂代谢异常的原因之一 ,而血脂异常的分布与 TG浓度升高有关     

Hydroxychloroquine has no significant effect on lipids and apolipoproteins in Chinese systemic lupus erythematosus patients with mild or inactive disease

OBJECTIVE: To investigate the effects of hydroxychloroquine (HCQ) in Chinese patients with systemic lupus erythematosus who were either on a low dose of prednisone or not on prednisone. METHODS: 65 consecutive Chinese lupus patients without features of nephritis underwent assessment of the fasting serum lipid profile, including total cholesterol (TC), triglycerides (TG), HDL-cholesteorl (HDL-C), LDL-cholesterol (LDL-C), apolipoprotein A-1 (apo A-1), apolipoprotein B (apo B) and lipoprotein (a) (Lp(a)). RESULTS: 44/65 (67.7%) patients were on HCQ with a dose of 244 +/- 86 mg daily and 34/65 (52.3%) patients were on 4.3 +/- 2.6 mg daily of prednisone. The percentages of patients taking prednisone and the mean dose in those patients receiving this treatment were not different between the groups with or without HCQ treatment. TG tended to be lower in those patients on HCQ (median and interquartile range) (1.0 (0.7-1.4) mmol/L vs 1.2 (0.8 1.6) mmol/L), but there were no significant differences in TC or other lipid parameters including Lp(a) between the 2 groups of patients with or without HCQ treatment. CONCLUSION: HCQ had no significant effect on the serum lipid profile in these lupus patients with mild or inactive disease. This finding probably reflects the low doses of corticosteroid used and a lower background lipid level in this population.     

A nine-month, placebo-controlled study of the effects of growth hormone treatment on lipoproteins and LDL size in abdominally obese men.

Abdominal/visceral obesity is associated with blunted growth hormone (GH) secretion and an unfavourable lipoprotein pattern. In this study, the effect of GH treatment on LDL size and on serum lipoprotein concentrations was determined in abdominally obese men. Thirty men, aged 48-66 years, with a body mass index (BMI) of 25-35 kg/m(2)and a waist:hip ratio of >0.95, received treatment with GH (9. 5 microg/kg/day) or placebo for 9 months.Serum concentrations of total cholesterol (TC), low density lipoprotein-cholesterol (LDL-C) and apolipoprotein B (apoB) were reduced (P<0.05, P<0.05 and P<0.001 vs placebo, respectively). Serum lipoprotein(a) [Lp(a)] concentration increased (P<0.05 vs. placebo). Mean low density lipoprotein (LDL) particle diameter was marginally increased by active treatment as compared with placebo (P =0.08). No changes were observed in the serum concentrations of high density lipoprotein-cholesterol (HDL-C), apolipoprotein A-I (apoA-I) and apolipoprotein E (apoE).In conclusion, 9 months of GH treatment in abdominally obese men beneficially reduced serum concentrations of TC, LDL-C and apoB, and marginally increased mean LDL diameter, while serum Lp(a) increased. The ultimate effect of GH therapy on the cardiovascular risk remains, however, to be determined.     

Taq1B CETP polymorphism, plasma CETP, lipoproteins, apolipoproteins and sex differences in a Jewish population sample characterized by low HDL-cholesterol

Mean high-density lipoprotein cholesterol (HDL-C) concentrations are low in the Jewish population of Israel. With this in mind we assessed the association of the Taq1B CETP polymorphism, plasma CETP mass and plasma lipid, lipoprotein and apolipoprotein concentrations in a sample of 884 Jerusalem residents aged 28-32. The allele frequency (0.435 +/- 0.017(S.E.)) is similar to that reported elsewhere. There was a strong (apparently codominant) association of the Taq1 B allele with plasma CETP in both sexes, and an inverse association with HDL-C and apo A-1, significant in women and undiminished upon adjustment for plasma CETP. There was evidence in this population for an admixture of two plasma CETP distributions, with 9% belonging to a distribution with the higher mean, pointing to a possible major gene effect. Mean plasma CETP was higher in women than men. Plasma CETP was inversely associated with HDL-C in men but not in women (P< 0.05 for the sex difference, multivariate analysis), inversely related to the HDL-C/apo A-1 ratio in men and positively related in women (P < 0.005 for the sex difference), and was positively associated with total cholesterol (TC) and low-density lipoprotein cholesterol in both sexes, and with the TC/HDL-C ratio and apo B in men alone. The sex differences may reflect dissimilarities in the regulatory function of CETP in lipid exchange. The absence of an unusual allele frequency of the Taq1B CETP polymorphism and its relatively modest association with HDL-C argue against an important role for this or strongly linked sites in determining the low population levels of HDL-C in Israel.