Workload, control, and social support effects on serum lipids: A longitudinal study among apparently healthy employed adults.

The authors investigated the direct and interactive effects of the job demand– control–support (JDC-S) model’s components on subsequent changes in high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides (TRI) separately for male and female employees. In contrast to all 14 past studies on these relationships, the authors used a longitudinal design. Study participants (N = 1,137, 66% men) were all apparently healthy employees who underwent a routine health check at 2 points in time (Time 1 and Time 2) about 22 months apart. In these analyses, the authors controlled for the Time 1 level of each criterion and for other confounders. Most of the direct and moderating effects found did not support the predictions of the JDC-S model; this finding is in agreement with the majority of past cross-sectional studies. The authors did not find any evidence supporting the existence of a reverse causation for either of the components of the JDC-S model. The authors suggest that serum lipids may not be a physiological mechanism mediating the effects of the JDC-S model on atherosclerotic diseases. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Plasma lipoprotein and apolipoprotein levels in Taipei and Framingham

We compared the plasma lipoprotein cholesterol, triglyceride, apolipoprotein (apo) A-I, apoB, and lipoprotein(a) [Lp(a)] concentrations in a low coronary heart disease (CHD) risk population (n = 440) in Taipei with a high CHD risk population (n = 428) in Framingham matched for age, sex, and menopausal status. Taipei men had significantly lower low-density lipoprotein cholesterol (LDL-C) (-20 mg/dL, -14%, P < .01) and apoB (-7 mg/dL, -6%, P < .05) levels and significantly higher high-density lipoprotein cholesterol (HDL-C) levels (6 mg/dL, 13%, P < .01) than Framingham men. Taipei women had significantly lower LDL-C (-18 mg/dL, -15%, P < .01) and higher HDL-C (4 mg/dL, 7%, P < .01) levels than Framingham women. Median concentrations and distributions of Lp(a) by sex were similar in Taipei and Framingham. After adjusting for body mass index and smoking status, only differences in total cholesterol and LDL-C levels remained significantly different for both sexes between the two populations (P < .01). Gender differences for lipids within populations were similar. After adjusting for age, body mass index, and smoking status, women in both Taipei and Framingham had significantly lower mean triglyceride, LDL-C, and apoB levels and significantly higher HDL-C and apoA-I levels than men. Postmenopausal women in Taipei had significantly higher mean total cholesterol, LDL-C, HDL-C, apoA-I, apoB, and Lp(a) levels than premenopausal women (P < .05), whereas in Framingham postmenopausal women had significantly higher total cholesterol, triglyceride, LDL-C, and apoB levels than premenopausal women (P < .05). Our data are consistent with the concept that plasma lipoprotein cholesterol levels (especially LDL-C) but not apolipoprotein values explain some of the twofold difference in age-adjusted CHD mortality between these two populations.     

Primary prevention of acute coronary events with lovastatin in men and women with average cholesterol levels: results of AFCAPS/TexCAPS. Air Force/Texas Coronary Atherosclerosis Prevention Study

CONTEXT: Although cholesterol-reducing treatment has been shown to reduce fatal and nonfatal coronary disease in patients with coronary heart disease (CHD), it is unknown whether benefit from the reduction of low-density lipoprotein cholesterol (LDL-C) in patients without CHD extends to individuals with average serum cholesterol levels, women, and older persons. OBJECTIVE: To compare lovastatin with placebo for prevention of the first acute major coronary event in men and women without clinically evident atherosclerotic cardiovascular disease with average total cholesterol (TC) and LDL-C levels and below-average high-density lipoprotein cholesterol (HDL-C) levels. DESIGN: A randomized, double-blind, placebo-controlled trial. SETTING: Outpatient clinics in Texas. PARTICIPANTS: A total of 5608 men and 997 women with average TC and LDL-C and below-average HDL-C (as characterized by lipid percentiles for an age- and sex-matched cohort without cardiovascular disease from the National Health and Nutrition Examination Survey [NHANES] III). Mean (SD) TC level was 5.71 (0.54) mmol/L (221 [21] mg/dL) (51 st percentile), mean (SD) LDL-C level was 3.89 (0.43) mmol/L (150 [17] mg/dL) (60th percentile), mean (SD) HDL-C level was 0.94 (0.14) mmol/L (36 [5] mg/dL) for men and 1.03 (0.14) mmol/L (40 [5] mg/dL) for women (25th and 16th percentiles, respectively), and median (SD) triglyceride levels were 1.78 (0.86) mmol/L (158 [76] mg/dL) (63rd percentile). INTERVENTION: Lovastatin (20-40 mg daily) or placebo in addition to a low-saturated fat, low-cholesterol diet. MAIN OUTCOME MEASURES: First acute major coronary event defined as fatal or nonfatal myocardial infarction, unstable angina, or sudden cardiac death. RESULTS: After an average follow-up of 5.2 years, lovastatin reduced the incidence of first acute major coronary events (1 83 vs 116 first events; relative risk [RR], 0.63; 95% confidence interval [CI], 0.50-0.79; P<.001), myocardial infarction (95 vs 57 myocardial infarctions; RR, 0.60; 95% CI, 0.43-0.83; P=.002), unstable angina (87 vs 60 first unstable angina events; RR, 0.68; 95% CI, 0.49-0.95; P=.02), coronary revascularization procedures (157 vs 106 procedures; RR, 0.67; 95% CI, 0.52-0.85; P=.001), coronary events (215 vs 163 coronary events; RR, 0.75; 95% CI, 0.61-0.92; P =.006), and cardiovascular events (255 vs 194 cardiovascular events; RR, 0.75; 95% CI, 0.62-0.91; P = .003). Lovastatin (20-40 mg daily) reduced LDL-C by 25% to 2.96 mmol/L (115 mg/dL) and increased HDL-C by 6% to 1.02 mmol/L (39 mg/dL). There were no clinically relevant differences in safety parameters between treatment groups. CONCLUSIONS: Lovastatin reduces the risk for the first acute major coronary event in men and women with average TC and LDL-C levels and below-average HDL-C levels. These findings support the inclusion of HDL-C in risk-factor assessment, confirm the benefit of LDL-C reduction to a target goal, and suggest the need for reassessment of the National Cholesterol Education Program guidelines regarding pharmacological intervention.     

Blood pressure, lipids, lipoproteins, body fat and physical activity of Singapore children

OBJECTIVE: To determine body composition, coronary risk factors and physical activity and the inter-relationships of these variables in Singaporean school children. METHODOLOGY: This study examined 1681 children (784 boys and 897 girls) from eight primary and seven secondary schools to determine percentiles for body stature and composition, blood pressure, lipids/lipoproteins and blood glucose by gender for three age divisions. An exercise and leisure pursuit questionnaire was administered to ascertain self-reported physical activity patterns. Anthropometric data and blood pressure readings were taken. Capillary blood was drawn from each child via finger prick sampling following an overnight fast. The concentrations of total cholesterol (TCHOL), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and glucose (GLU) were determined from plasma using a dry chemistry analyser. Low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL) and the TCHOL/HDL-C ratio were determined by calculation. RESULTS: While 47.7% of boys and 22.0% of girls disclosed active lifestyles, differences between the active and non-active children were found in coronary risk factors TCHOL, LDL-C, TG, TCHOL/HDL-C and per cent body fat. No differences were shown between the two groups in HDL-C, GLU and blood pressure. There was a high correlation between the various measures of body composition with the highest correlation (r = 0.806, P < 0.001) found between body mass index (BMI) and waist measurements. CONCLUSIONS: Children in this study who reported no activity or relatively little activity were found to have TCHOL, LDL-C, TG, TCHOL/HDL-C and per cent body fat that were higher than those who reported moderately high or vigorous physical activity patterns.     

The association of education with coronary heart disease mortality in the USSR Lipid Research Clinics Study

There is a strong inverse association between educational attainment and coronary heart disease (CHD) mortality in men in the USSR Lipid Research Clinics (LRC) Study. Less educated men were characterized by higher mean blood pressure, high density lipoprotein cholesterol (HDL-C), cigarettes smoked and by lower mean low density lipoprotein cholesterol (LDL-C) and body mass index (BMI). With respect to nutritional variables, less educated men were characterized by higher mean energy per kg body weight and alcohol intake and by lower mean intake of fat, saturated, mono- and polyunsaturated fatty acids, cholesterol, sucrose, and other sugars. The Keys score closely predicted the differences in plasma cholesterol among the educational groups in the randomly selected sample. In men without CHD at entry, the age and clinic-adjusted relative risk for CHD mortality was 2.4 for the least educated compared with the most educated group; on adjusting for systolic blood pressure, HDL-C, LDL-C, BMI, alcohol intake and number of cigarettes, the relative risk was reduced to 1.9. These data indicate that only 22% of the twofold excess of CHD mortality associated with low education was statistically attributable to the major risk factors. The failure to explain more of the education-CHD mortality gradient in the USSR LRC cohort was similar to observations from cohort studies in Great Britain and the US. Other correlates of low education must be explored to explain the association.     

Associations between acute lipid stress responses and fasting lipid levels 3 years later.

The authors assessed the association between lipid responses to acute mental stress and fasting serum lipid levels 3 years later in 199 middle-aged men and women. Total cholesterol, low-density lipoprotein (LDL), and high-density lipoprotein (HDL) cholesterol increased following moderately stressful behavioral tasks. LDL cholesterol, HDL cholesterol, and total:HDL ratio measured 3 years later were predicted by acute stress responses independent of gender, age, socioeconomic position, change in body mass, smoking, alcohol consumption, or hormone replacement therapy baseline lipid levels. The odds of clinically elevated cholesterol were significantly greater in the highest compared with the lowest stress tertile, independent of baseline levels and covariates. Acute lipid stress responsivity may reflect processes that contribute to the development of elevated blood cholesterol concentration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Clinical characteristics and coronary risk factors of patients with low concentrations of serum low-density lipoprotein cholesterol and total cholesterol

We investigated the clinical characteristics and coronary risk factors of Chinese patients with suspected coronary artery disease (CAD) having low serum concentrations of both low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC). Of 1,450 patients with suspected CAD (age range, 30-92 years; 948 men and 502 women), 760 had established CAD. The patients were divided into three groups according to lipid profile patterns. Group 1 patients (n = 138) had low LDL-C concentrations (< 100 mg/dL) and low TC concentrations (< 160 mg/dL). They were characterized by lower triglyceride concentrations, lower frequencies of high TC/high-density lipoprotein cholesterol (HDL-C) ratios (> 5) and LDL-C/HDL-C ratios (> 5), and lower frequencies of a family history of CAD and obesity. Group 3 patients (n = 610) had LDL-C concentrations of 130 mg/dL or above and TC concentrations of 200 mg/dL or above, much higher than in group 1. The prevalence of CAD was 41.3% (57/138) in group 1. 46.7% (328/702) in group 2, and 61.5% (375/610) in group 3. Groups with higher TC and LDL-C concentrations had a higher CAD prevalence. Coronary risk factors of group 1 patients appeared to be low HDL-C concentration, high TC/HDL-C ratio, advanced age, cigarette smoking, hypertension, and diabetes mellitus. Among these risk factors, HDL-C and hypertension were independent predictors of CAD. Unlike in the other two groups, hypertension was the only independent nonlipid risk factor. We conclude that in therapy or prevention of CAD, the goals should be to reduce LDL-C concentration to below 100 mg/dL and the TC concentration to below 160 mg/dL. However, other risk factors should also be considered.     

Central markers of body fat distribution are important predictors of plasma lipids in elderly men and women

We determined the contribution of body fat distribution, peak VO2, fat mass, and dietary intake to variation in plasma lipids in elderly individuals. Volunteers were a healthy cohort of older Caucasian women (n = 75, mean age +/- SD, 72 +/- 5 years) and older men (n = 101, 72 +/- 5 years). We determined fat mass from underwater weighing, fat patterning from waist circumference, as well as peripheral and truncal skinfolds, exercise capacity from peak VO2, and dietary intake from three-day food diaries. Plasma lipid levels were measured in the fasting state and included total cholesterol, high density lipoprotein (HDL-C), low density lipoprotein (LDL-C), and fasting triglycerides. Older women weighted less than older men, but had higher fat mass, truncal, and peripheral skinfolds. Waist circumference and peak VO2 were lower in older women than older men. Older women had higher total cholesterol (217 +/- 31 vs. 197 +/- 30; p < 0.01), HDL-C (54 +/- 12 vs. 49 +/- 14; p < 0.05), and LDL-C (133 +/- 26 vs. 121 +/- 27; p < 0.01) when compared with older men. No gender differences were noted in fasting triglycerides. Truncal skinfolds were the best predictor of plasma lipids in older men, accounting for between 9% and 30% (r2) of the variation in plasma lipids. Similarly, in older women, central markers of fatness (i.e., waist circumference and truncal skinfolds) were the best predictors of plasma lipids (r2 = 3% to 24%). Total fat mass, peak VO2 and dietary intake were not independent predictors of plasma lipids in older men and women. Indices of central body fatness, rather than total fat mass, peak VO2 or dietary intake are stronger predictors of plasma lipids in healthy older men and women.     

A comparison of estrogen replacement, pravastatin, and combined treatment for the management of hypercholesterolemia in postmenopausal women

OBJECTIVES: To evaluate and compare the lipid-altering effects of conjugated estrogens and pravastatin, alone and in combination, in postmenopausal women with hypercholesterolemia. METHODS: This was a double-blind, randomized, placebo-controlled clinical trial with 4 parallel groups. Participants (N = 76) were randomly assigned to receive conjugated estrogens, 0.625 mg/d; pravastatin sodium, 20 mg/d; conjugated estrogens plus pravastatin; or a placebo for 16 weeks. RESULTS: Primary end points were changes in serum lipid parameters. Among participants treated with conjugated estrogens, levels of non-high density lipoprotein cholesterol (non-HDL-C) (13.0%) and calculated low density lipoprotein cholesterol (LDL-C) (13.5%) decreased, while levels of HDL-C (22.5%) and triglycerides (4.2%) increased. Participants in the pravastatin group achieved reductions of 23.7% and 25.4% in non-HDL-C and calculated LDL-C levels, respectively. Levels of HDL-C increased slightly (3.7%) and triglycerides decreased by 12.1%. Among participants treated with a combination of conjugated estrogens plus pravastatin, the non-HDL-C (-25.2%) and calculated LDL-C (-28.7%) responses were similar to those of the pravastatin group, and the HDL-C response (21.2%) was similar to that observed in the conjugated estrogens group. Triglyceride levels remained similar to baseline (-0.9%) in the combined treatment group. CONCLUSIONS: Administration of conjugated estrogens resulted in potentially antiatherogenic changes in levels of non-HDL-C, HDL-C, and calculated LDL-C. The HDL-C response to combined treatment was similar to that observed in women taking conjugated estrogens alone, while the non-HDL-C and LDL-C responses to combined treatment were similar to those produced by pravastatin therapy alone. These findings support the position of the National Cholesterol Education Program that estrogen replacement, with a progestin where indicated, should be given consideration as a therapeutic option for the management of hypercholesterolemia in postmenopausal women.     

Relationship between acute diarrhoea and low plasma levels of vitamin A and retinol binding protein

OBJECTIVE: We studied possible sex differences of the effect of fenofibrate on serum lipoproteins. Twenty-three patients with primary hypercholesterolaemia (10 postmenopausal women and 13 aged-matched men) were treated with slow-release fenofibrate for 96 weeks. RESULTS: Steady state lipoprotein concentrations were reached after 12 and 24 weeks of treatment in women and men, respectively. During the subsequent follow-up the lipoprotein concentrations remained constant. In women total and low-density lipoprotein (LDL) cholesterol decreased from 299 to 234 mg.dl-1 and from 210 to 151 mg.dl-1, respectively, and in men from 265 to 233 mg.dl-1 and from 192 to 160 mg.dl-1. The decrease in triglycerides was also more pronounced in women (-42%) than in men (-18%). High-density lipoprotein (HDL) cholesterol increased significantly in women from 53 to 63 mg.dl-1 but not in men (45 to 50 mg.dl-1). Since the changes in LDL and HDL cholesterol occurred in opposite directions, the decrease in LDL/HDL cholesterol ratio was accentuated in both groups. However, this ratio was decreased almost twofold in women (-41%) compared to men (-23%). Although the serum concentrations of fenofibric acid were 1.3-fold higher in women than in men, which was probably due to the higher body weight in men (1.2-fold), this difference can hardly explain the favorable effect on lipoproteins in women. CONCLUSION: The present study indicates that fenofibrate might be very effective by reducing the concentrations of atherogenic lipoproteins in postmenopausal women.     

Biological variability in serum vitamin E concentrations: relation to serum lipids

The components of biological variation in serum vitamin E in relation to serum cholesterol, triglycerides, high- and low-density lipoprotein cholesterol (HDL-C, LDL-C), apolipoprotein A-I (apo A-I), and apo B were examined in 26 healthy volunteers who had monthly blood samplings during one calendar year. The estimated CVs for vitamin E were: interindividual, 19.9%, and intraindividual, 11.9%; the index of individuality (I-index) was 0.59. The I-indices for all lipid variables were < 0.51. Serum concentrations of vitamin E, cholesterol, triglycerides, HDL-C, LDL-C, and apo B were lower in spring than in the other seasons. The peak-trough differences in the yearly variations, expressed as a percentage of the mean, were for vitamin E 14.5%, cholesterol 16.2%, triglycerides 14.5%, and LDL-C 24.3%. A significant common annual rhythm was expressed in vitamin E or lipid variables and in the changes in ambient temperature the weeks before blood sampling (inverse relations). There were highly significant positive time relations between serum vitamin E and cholesterol, triglycerides, and apo B. Subjects with higher homeostatic setpoints of cholesterol showed higher homeostatic setpoints of vitamin E, triglycerides, LDL-C, and apo B.     

Evoked potentials (VEPs and BAEPs) in a large cohort of short- and long-term haemodialysed patients

OBJECTIVE: To compare the effects of diets containing high or low amounts of n-3 fatty acids on lipid levels in men. DESIGN: A continuous 40-day feeding study was conducted using a 5-day cycle menu. The control diet, which was fed the first 21 days of the trial, contained 32% of energy as fat and 44.4 g total dietary fiber per day. Total serum cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TGs) were evaluated 1 day before the trial began and on days 21 and 41. SUBJECTS: 17 men aged 21 to 42 years who were free-living individuals with no apparent illnesses or hyperlipidemia. INTERVENTION: The treatment diets, which were substituted daily for the regular entrees for the last 19 days of the trial, contained 180 g/day of either farm-raised catfish or wild Alaskan salmon. STATISTICAL ANALYSES PERFORMED: Serum data were analyzed using analysis of covariance with the initial values as the covariates. RESULTS: After 21 days on the control diet, TC and TGs decreased; however, there were no further decreases during the last 19 days when fish was consumed. LDL-C remained unchanged after the first 21 days but was lower than the initial value by day 41. HDL-C levels were similar over the 40 days. There were no significant differences in lipid levels of men who consumed catfish and those who consumed salmon. APPLICATIONS/CONCLUSIONS: Farm-raised catfish compared favorably to wild Alaskan salmon when incorporated into the total diet in regard to lipid levels in men.     

Effects of dexamethasone on functional and pathological changes in rat bronchi caused by high acute exposure to chlorine

OBJECTIVE: To assess month-to-month variability of total cholesterol, triglycerides, high-density lipoprotein-cholesterol (HDL-C), calculated low-density lipoprotein-cholesterol (LDL-C), apolipoprotein A1, apolipoprotein B, and lipoprotein (a), as well as factors that could influence variability, including recent acute infection in an adolescent population. METHODS: Sixty-three high school students had fasting lipids and lipoproteins measured at 4 separate times during the school year and another venipuncture 3 to 7 days after recovery from an acute infection. Erythrocyte sedimentation rate was also measured. Coefficients of variation were calculated for each study variable. The influence of recent infection on variability was assessed. RESULTS: The 50th and 95th percentiles, respectively, for the coefficient of variation for each variable were as follows: total cholesterol, 7.3% and 13.6%; triglycerides, 22% and 47.3%; HDL-C, 7.9% and 16.8%; LDL-C, 12.1% and 25%; apolipoprotein A1, 6.3% and 15.2%; apolipoprotein B, 9.5% and 17.2%; and lipoprotein (a), 19.3% and 40%. Recent infection significantly lowered HDL-C (4 mg/dL; P < .0001) and apolipoprotein A1 (7 mg/dL; P < .005). CONCLUSIONS: Clinicians evaluating lipids and lipoproteins serially should expect significant visit-to-visit variation in triglycerides and calculated LDL-C values. Assessment of HDL-C and apolipoprotein A1 should not be done within 2 weeks of an acute infection. Apolipoproteins B and A1 have slightly less variability than their respective lipoprotein cholesterol values (LDL-C and HDL-C).     

Exercise training induced alterations in prepubertal children's lipid-lipoprotein profile

PURPOSE: This study examined the effect of exercise training on prepubertal children's (ET, N = 28) lipid-lipoprotein profile, relative to a maturity matched control group (CON, N = 20). METHODS: Training for ET involved stationary cycling for 30 min, 3 times.wk-1 for 12 wk, at 79.3 +/- 1.2% (mean +/- SD) peak heart rate (HR). Controls maintained their usual lifestyle pattern. Plasma concentrations of total triacylglycerol (TG), total cholesterol (TC), and high-density lipoprotein (HDL)-cholesterol (HDL-C) were determined pre- and postintervention. Low-density lipoprotein (LDL)- cholesterol (LDL-C) was subsequently estimated from these concentrations, and the ratios TC/HDL-C and LDL-C/HDL-C were also calculated. There were no pretest differences (P > 0.05) for any of these blood analytes between groups. The following, potentially, confounding variables were also measured: peak VO2, percent body fat (%BF), dietary composition, and habitual physical activity. These variables, with pretest HDL-C, were included as covariates in two-way split plot ANCOVA analyses. Dietary variables were not included as covariates as they were not related to any of the blood analytes. RESULTS: There were no differences over time or between groups for TG and TC (P > 0.05). LDL-C decreased in ET (-10.2%) but remained unchanged in CON (0.3%) over the intervention period (P < 0.05). HDL-C increased in ET (9.3%) but decreased in CON (-8.9%) (P < 0.01). A similar, but inverted, pattern of change (P < 0.01) was revealed for both ratios, TC/HDL-C (-11.6% vs 6.3%, ET and CON, respectively), and LDL-C/HDL-C (-17.2% vs 8.0%, ET and CON, respectively). The favorable alterations in the lipid-lipoprotein profile for ET were independent of alterations in peak VO2 (group x time interaction, P < 0.05), %BF (main effect time, P < 0.01), and habitual physical activity (group x time interaction, P < 0.01). CONCLUSIONS: In conclusion, the favorable alterations in the lipoprotein profile seen in this study would suggest that it is possible to influence the prepubertal lipoprotein profile independent of alterations in confounding variables such as body composition, cardiorespiratory fitness, and habitual physical activity.     

Effects of gender and menopausal status on plasma lipoprotein subspecies and particle sizes

The risk of coronary heart disease (CHD) is lower in women than in men, but increases in women after menopause. Some of the gender, age, and menopausal-related differences in CHD risk may relate to differences in lipoprotein subspecies. We therefore examined these subspecies in three groups of healthy subjects: premenopausal women (W, n = 72, mean age 41.2 +/- 6.5), postmenopausal women (PMW, n = 74, 55.8 +/- 7.4), and men (M, n = 139, 48.8 +/- 10.7). We measured plasma levels of lipids, lipoprotein cholesterol, apolipoproteins A-I, A-IV, B, C-III, and E, and lipoprotein subspecies Lp A-I, Lp A-I:A-II, Lp B, Lp B:C-III, and Lp B:E, as well as LDL and HDL particle sizes. Our data indicate that women have significantly higher values of HDL-C, apoA-I, apoE, and Lp A-I; larger LDL and HDL particle sizes; and lower values of triglyceride, apoB, and Lp B:C-III particles than men, with no difference in Lp A-I:A-II. Postmenopausal status was associated with significantly higher values of total cholesterol, triglyceride, VLDL-C, and LDL-C; increased levels of apoB, C-III, and E; elevated values of Lp B, Lp B:C-III, and Lp B:E; and lower levels of HDL-C along with smaller HDL particle size. Moreover, we noted a strong correlation between LDL and HDL particle size. Our data are consistent with the concepts that male gender confers decreases in HDL subspecies due to lower Lp A-I levels; while postmenopausal status results in higher levels of all apoB-containing lipoproteins (Lp B, Lp B:C-III, and Lp B:E). The lipoprotein alterations associated with male gender and postmenopausal status would be expected to increase CHD risk.     

Fasting insulin and apolipoprotein B levels and low-density lipoprotein particle size as risk factors for ischemic heart disease

CONTEXT: Epidemiological studies have established a relationship between cholesterol and low-density lipoprotein cholesterol (LDL-C) concentrations and the risk of ischemic heart disease (IHD), but up to half of patients with IHD may have cholesterol levels in the normal range. OBJECTIVE: To assess the ability to predict the risk of IHD using a cluster of nontraditional metabolic risk factors that includes elevated fasting insulin and apolipoprotein B levels as well as small, dense LDL particles. DESIGN: Nested case-control study. SETTING: Cases and controls were identified from the population-based cohort of the Quebec Cardiovascular Study, a prospective study conducted in men free of IHD in 1985 and followed up for 5 years. PARTICIPANTS: Incident IHD cases were matched with controls selected from among the sample of men who remained IHD free during follow-up. Matching variables were age, smoking habits, body mass index, and alcohol consumption. The sample included 85 complete pairs of nondiabetic IHD cases and controls. MAIN OUTCOME MEASURES: Ability of fasting insulin level, apolipoprotein B level, and LDL particle diameter to predict IHD events, defined as angina, coronary insufficiency, nonfatal myocardial infarction, and coronary death. RESULTS: The risk of IHD was significantly increased in men who had elevated fasting plasma insulin and apolipoprotein B levels and small, dense LDL particles, compared with men who had normal levels for 2 of these 3 risk factors (odds ratio [OR], 5.9; 95% confidence interval [CI], 2.3-15.4). Multivariate adjustment for LDL-C, triglycerides, and high-density lipoprotein cholesterol (HDL-C) did not attenuate the relationship between the cluster of nontraditional risk factors and IHD (OR, 5.2; 95% CI, 1.7-15.7). On the other hand, the risk of IHD in men having a combination of elevated LDL-C and triglyceride levels and reduced HDL-C levels was no longer significant (OR, 1.4; 95% CI, 0.5-3.5) after multivariate adjustment for fasting plasma insulin level, apolipoprotein B level, and LDL particle size. CONCLUSION: Results from this prospective study suggest that the measurement of fasting plasma insulin level, apolipoprotein B level, and LDL particle size may provide further information on the risk of IHD compared with the information provided by conventional lipid variables.     

Cell surface binding and cellular internalization properties of suramin, a novel antineoplastic agent

BACKGROUND: A number of factors contribute to increased risk of coronary heart disease (CHD) among postmenopausal women, including atherogenic changes in serum cholesterol profiles, weight gain, and decreases in physical activity during the menopause. To date, no study has attempted to prevent elevations in primary CHD risk factors as women experience menopause. METHODS: A sample of 535 healthy premenopausal women, ages 44-50, were recruited for an ongoing 5-year randomized prevention trial testing whether increases in low-density lipoprotein cholesterol (LDL-C) and body weight can be prevented during the menopause with a dietary and behavioral intervention. The aim was to reduce total dietary and saturated fat and cholesterol, prevent weight gain, and increase physical activity levels. Changes in CHD risk factors after the first 6 months of treatment were analyzed comparing 253 intervention and 267 assessment-only control participants. RESULTS: The intervention group showed significant reductions in total cholesterol (-0.34 mmol/liter), LDL-C (-0.28 mmol/liter), triglycerides (-0.04 mmol/liter), weight (-4.8 kg), waist-hip ratio (-0.008), systolic blood pressure (-3.5 mm Hg), diastolic blood pressure (-2.2 mm Hg), serum glucose levels (-0.06 mmol/liter), and HDL-C (-0.06 mmol/liter) and significant increases in physical activity (+383 kcal). No significant changes were observed in the control group. CONCLUSION: Six-month results suggested that participants were receptive to the preventive approach to CHD risk reduction and were successful in making initial positive lifestyle changes. Follow-up data will evaluate long-term adherence to the intervention and the interaction between adherence and physiological changes during menopause.     

Changes in physical activity and health outcomes in a population-based cohort of mid-life Australian-born women

Cross-sectional studies and intervention programs have suggested that physical activity is a potential contributor to the health and wellbeing of mid-life and older women. This prospective longitudinal study investigates whether natural changes in physical activity are associated with changes in health outcomes in a population-based cohort of Australian-born women aged 45-55 years living in Melbourne. Of the 352 women from the Melbourne Women's Midlife Health Project who filled in a base-line physical activity questionnaire, 292 (83 per cent) were evaluated around three years later with regard to physical activity, psychological wellbeing, self-rated health, symptoms experienced, body mass index (BMI), blood pressure and serum lipids. Mean (SD) physical activity measured at base-line was 5.9 (5.7) hours/week, or 1496 (1449) kcal/week; mean (SD) change in physical activity per week was 0.05 (5.24) hours, or 44 (1347) kcal, indicating that although mean change was small there was substantial variation in change. There were significant increases in BMI (P < 0.001), wellbeing (P < 0.05), the number of reported menopause-related symptoms, and high-density lipoprotein cholesterol (HDL-C) levels (P < 0.001), and a decrease in low-density lipoprotein cholesterol (LDL-C) levels (P < 0.05). Change in level of physical activity was positively associated with change in HDL-C (P < 0.01) and change in wellbeing (P = 0.08) and negatively associated with change in coronary heart disease risk score. By increasing physical activity in mid-life, women may reduce at least one risk factor (HDL-C) associated with coronary heart disease.     

Characterization of the proliferation state in canine mammary tumors by the standardized AgNOR method with postfixation and immunohistologic detection of Ki-67 and PCNA

Recently, there have been some reports that changes in serum lipid composition may be related to suicide, major depression and immune-inflammatory responses. Findings from our laboratory suggest that major depression is accompanied by reduced formation of cholesteryl esters and perhaps by impairment of reverse cholesterol transport. The latter is reportedly accompanied by lower serum high-density lipoprotein cholesterol (HDL-C). The aim of this study was to examine whether (i) major depression is accompanied by lower serum HDL-C or by abnormal levels of serum total cholesterol, triglycerides, low-density lipoprotein-C (LDL-C) or vitamin E, (ii) suicidal attempts are related to lower serum HDL-C and (iii) there are significant associations between serum HDL-C and immune/inflammatory markers. A total of 36 subjects with major depression, of whom 28 patients showed treatment resistance, as well as 28 normal control subjects, had blood sampled for the assay of the above lipids, serum zinc (Zn), albumin (Alb) and flow cytometric determination of the T-helper/T-suppressor (CD4+/CD8+) T-cell ratio. In total, 28 depressed subjects had repeated measures of these variables both before and after treatment with antidepressants. Serum HDL-C and total cholesterol, as well as the HDL-C/cholesterol ratio, were significantly lower in subjects with major depression than in normal controls. Serum HDL-C levels were significantly lower in depressed men who had at some time made serious suicidal attempts than in those without such suicidal behaviour. Treatment with antidepressants for 5 weeks did not significantly alter either serum HDL-C or other lipid variables. Serum HDL-C levels were significantly and negatively correlated with the (CD4+/CD8+) T-cell ratio, and positively correlated with serum Alb and Zn. These results suggest that (i) lower serum HDL-C levels are a marker for major depression and suicidal behaviour in depressed men, (ii) lower serum HDL-C levels are probably induced by the immune/inflammatory response in depression and (iii) there is impairment of reverse cholesterol transport from the body tissues to the liver.