Connecting the dots between breast cancer, obesity and alcohol consumption in middle-aged women: ecological and case control studies

Background

Breast cancer (BC) incidence in Australian women aged 45 to 64 years (‘middle-aged’) has tripled in the past 50 years, along with increasing alcohol consumption and obesity in middle-age women. Alcohol and obesity have been individually associated with BC but little is known about how these factors might interact. Chronic psychological stress has been associated with, but not causally linked to, BC. Here, alcohol could represent the ‘missing link’ – reflecting self-medication. Using an exploratory cross-sectional design, we investigated inter-correlations of alcohol intake and overweight/obesity and their association with BC incidence in middle-aged women. We also explored the role of stress and various lifestyle factors in these relationships.

Methods

We analysed population data on BC incidence, alcohol consumption, overweight/obesity, and psychological stress. A case control study was conducted using an online survey. Cases (n = 80) were diagnosed with BC and controls (n = 235) were women in the same age range with no BC history. Participants reported lifestyle data (including alcohol consumption, weight history) over consecutive 10-year life periods. Data were analysed using a range of bivariate and multivariate techniques including correlation matrices, multivariate binomial regressions and multilevel logistic regression.

Results

Ecological inter-correlations were found between BC and alcohol consumption and between BC and obesity but not between other variables in the matrix. Strong pairwise correlations were found between stress and alcohol and between stress and obesity.

BMI tended to be higher in cases relative to controls across reported life history. Alcohol consumption was not associated with case-control status. Few correlations were found between lifestyle factors and stress, although smoking and alcohol consumption were correlated in some periods. Obesity occurring during the ages of 31 to 40 years emerged as an independent predictor of BC (OR 3.5 95% CI: 1.3–9.4).

Conclusions

This study provides ecological evidence correlating obesity and alcohol consumption with BC incidence. Case-control findings suggest lifetime BMI may be important with particular risk associated with obesity prior to 40 years of age. Stress was ecologically linked to alcohol and obesity but not to BC incidence and was differentially correlated with alcohol and smoking among cases and controls. Our findings support prevention efforts targeting weight in women below 40 years of age and, potentially, lifelong alcohol consumption to reduce BC risk in middle-aged women.

Heritability of Biomarkers of Oxidized Lipoproteins: Twin Pair Study

OBJECTIVE

To determine whether biomarkers of oxidized lipoproteins are genetically determined. Lipoprotein(a) (Lp[a]) is a heritable risk factor and carrier of oxidized phospholipids (OxPL).

APPROACH AND RESULTS

We measured oxidized phospholipids on apolipoprotein B-containing lipoproteins (OxPL-apoB), Lp(a), IgG, and IgM autoantibodies to malondialdehyde-modified low-density lipoprotein, copper oxidized low-density lipoprotein, and apoB-immune complexes in 386 monozygotic and dizygotic twins to estimate trait heritability (h(2)) and determine specific genetic effects among traits. A genome-wide linkage study followed by genetic association was performed. The h(2) (scale: 0-1) for Lp(a) was 0.91±0.01 and for OxPL-apoB 0.87±0.02, which were higher than physiological, inflammatory, or lipid traits. h(2) of IgM malondialdehyde-modified low-density lipoprotein, copper oxidized low-density lipoprotein, and apoB-immune complexes were 0.69±0.04, 0.67±0.05, and 0.80±0.03, respectively, and for IgG malondialdehyde-modified low-density lipoprotein, copper oxidized low-density lipoprotein, and apoB-immune complexes 0.62±0.05, 0.52±0.06, and 0.53±0.06, respectively. There was an inverse correlation between the major apo(a) isoform and OxPL-apoB (R=-0.49; P<0.001) and Lp(a) (R=-0.48; P<0.001) and OxPL-apoB was modestly correlated with Lp(a) (ρ=0.57; P<0.0001). The correlation in major apo(a) isoform size was concordant (R=1.0; P<0.001) among monozygotic twins but not dizygotic twins (R=0.40; P=0.055). Lp(a) and OxPL-apoB shared genetic codetermination (genetic covariance, ρG=0.774±0.032; P=1.09×10(-38)), although not environmental determination (environmental covariance, ρE=0.081±0.15; P=0.15). In contrast, Lp(a) shared environmental but not genetic codetermination with autoantibodies to malondialdehyde-modified low-density lipoprotein and copper oxidized low-density lipoprotein, and apoB-immune complexes. Sib-pair genetic linkage of the Lp(a) trait revealed that single nucleotide polymorphism rs10455872 was significantly associated with OxPL-apoB after adjusting for Lp(a).

CONCLUSIONS

OxPL-apoB and other biomarkers of oxidized lipoproteins are highly heritable cardiovascular risk factors that suggest novel genetic origins of atherothrombosis.

Oxidized phospholipids are present on plasminogen, affect fibrinolysis, and increase following acute myocardial infarction

OBJECTIVES

This study sought to assess whether plasminogen, which is homologous to lipoprotein (a) [Lp(a)], contains proinflammatory oxidized phospholipids (OxPL) and whether this has clinical relevance.

BACKGROUND

OxPL measured on apolipoprotein B-100 (OxPL/apoB), primarily reflecting OxPL on Lp(a), independently predict cardiovascular disease (CVD) events.

METHODS

The authors examined plasminogen from commercially available preparations and plasma from chimpanzees; gorillas; bonobos; cynomolgus monkeys; wild-type, apoE(-/-), LDLR(-/-), and Lp(a)-transgenic mice; healthy humans; and patients with familial hypercholesterolemia, stable CVD, and acute myocardial infarction (AMI). Phosphocholine (PC)-containing OxPL (OxPC) present on plasminogen were detected directly with liquid chromatography-mass spectrometry (LC-MS/MS) and immunologically with monoclonal antibody E06. In vitro clot lysis assays were performed to assess the effect of the OxPL on plasminogen on fibrinolysis.

RESULTS

LC-MS/MS revealed that OxPC fragments were covalently bound to mouse plasminogen. Immunoblot, immunoprecipitation, density gradient ultracentrifugation, and enzyme-linked immunosorbent assay analyses demonstrated that all human and animal plasma samples tested contained OxPL covalently bound to plasminogen. In plasma samples subjected to density gradient fractionation, OxPL were present on plasminogen (OxPL/plasminogen) in non-lipoprotein fractions but on Lp(a) in lipoprotein fractions. Plasma levels of OxPL/apoB and OxPL/apo(a) varied significantly (>25×) among subjects and also strongly correlated with Lp(a) levels. In contrast, OxPL/plasminogen levels were distributed across a relatively narrow range and did not correlate with Lp(a). Enzymatic removal of OxPL from plasminogen resulted in a longer lysis time for fibrin clots (16.25 vs. 11.96 min, p = 0.007). In serial measurements over 7 months, OxPL/plasminogen levels did not vary in normal subjects or in patients with stable CVD, but increased acutely over the first month and then slowly decreased to baseline in patients following AMI.

CONCLUSIONS

These data demonstrate that plasminogen contains covalently bound OxPL that influence fibrinolysis. OxPL/plasminogen represent a second major plasma pool of OxPL, in addition to those present on Lp(a). OxPL present on plasminogen may have pathophysiological implications in AMI and atherothrombosis.

Abstract 490: Distribution of Oxidized Phospholipids and Lipoprotein-Associated Phospholipase A2 in Plasma, Density Gradient Fractions and Individual Lipoproteins in Patients with Familial Hypercholesterolemia: Effect of LDL Apheresis

Objectives: Lipoprotein(a)[Lp(a)] is a causal, genetic risk factor for cardiovascular disease(CVD) and is enriched in pro-inflammatory oxidized phospholipids(OxPL) and lipoprotein-associated phospholipase A2(Lp-PLA2). Epidemiologic outcome studies have shown that the OxPL, Lp(a) and Lp-PLA2 collectively mediate additive risk for CVD.

Methods: To derive insights into the relationships between Lp(a), OxPL and Lp-PLA2, 18 patients with familial hypercholesterolemia(FH) and Low(<10mg/dl), Intermediate (∼50mg/dl) or High(>100mg/dl) Lp(a) levels on chronic LDL apheresis were evaluated. Twenty-five isopycnic density fractions(density <1.015 to >1.189 g/ml) were isolated from pre and post apheresis plasma(n=50 fractions per patient). OxPL and Lp-PLA2 mass and activity were quantitated with a variety of techniques under 3 conditions: in plasma, in each density fraction with direct plating techniques and on individual lipoproteins within each density fraction by using antibody capture assays to apoB-100(OxPL/apoB and Lp-PLA2/apoB), Lp(a)[OxPL/apo(a) and Lp-PLA2/apo(a)] and apoA-I(OxPL/apoA-I and Lp-PLA2/apoA-I)(total of 900 fractions per measure) and detecting OxPL and Lp-PLA2 with monoclonal antibodies E06 and 4B4, respectively.

Results: In whole density gradients by direct plating techniques, OxPL were almost exclusively detected in the Lp(a) containing fractions(density 1.059-1.094 g/ml) and Lp-PLA2 mass and activity were present between the apoB and Lp(a) density fractions. In lipoprotein capture assays, OxPL/apoB and OxPL/apo(a) increased proportionally with increasing Lp(a) levels; Lp-PLA2/apoB and Lp-PLA2/apoA-I levels were highest in patients with Low Lp(a) but decreased proportionally with increasing Lp(a) levels; Lp-PLA2/apo(a) was lowest in patients with Low Lp(a) levels and increased proportionally with increasing Lp(a) levels. LDL apheresis significantly reduces levels of OxPL and Lp-PLA2 on apoB and Lp(a), particularly in patients with high Lp(a) levels

Conclusions: This study documents that OxPL are primarily present on Lp(a) and Lp-PLA2 primarily on apoB, but the proportion of each increases on Lp(a) and decreases on apoB as plasma Lp(a) levels increase. These data suggest a pathophysiological relationship between Lp(a), OxPL and Lp-PLA2 and provide a rationale for understanding how they collectively mediate CVD in humans.

Relationship of IgG and IgM autoantibodies and immune complexes to oxidized LDL with markers of oxidation and inflammation and cardiovascular events: results from the EPIC-Norfolk Study

Levels of IgG and IgM autoantibodies (AA) to malondialdehyde (MDA)-LDL and apoB-immune complexes (ICs) were measured in 748 cases and 1,723 controls in the EPIC-Norfolk cohort and their association to coronary artery disease (CAD) events determined. We evaluated whether AA and IC modify CAD risk associated with secretory phospholipase A(2) (sPLA(2)) type IIA mass and activity, lipoprotein-associated PLA(2) activity, lipoprotein (a) [Lp(a)], oxidized phospholipids on apoB-100 (OxPL/apoB), myeloperoxidase, and high sensitivity C-reactive protein. IgG ICs were higher in cases versus controls (P = 0.02). Elevated levels of IgM AA and IC were inversely associated with Framingham Risk Score and number of metabolic syndrome criteria (p range 0.02-0.001). In regression analyses adjusted for age, smoking, diabetes, LDL-cholesterol, HDL-cholesterol, and systolic blood pressure, the highest tertiles of IgG and IgM AA and IC were not associated with higher risk of CAD events compared with the lowest tertiles. However, elevated levels of IgM IC reduced the risk of Lp(a) (P = 0.006) and elevated IgG MDA-LDL potentiated the risk of sPLA(2) mass (P = 0.018). This epidemiological cohort of initially healthy subjects shows that IgG and IgM AA and IC are not independent predictors of CAD events but may modify CAD risk associated with elevated levels of oxidative biomarkers.

Changes in lipoprotein(a), oxidized phospholipids, and LDL subclasses with a low-fat high-carbohydrate diet

Low-fat diets have been shown to increase plasma concentrations of lipoprotein(a) [Lp(a)], a preferential lipoprotein carrier of oxidized phospholipids (OxPLs) in plasma, as well as small dense LDL particles. We sought to determine whether increases in plasma Lp(a) induced by a low-fat high-carbohydrate (LFHC) diet are related to changes in OxPL and LDL subclasses. We studied 63 healthy subjects after 4 weeks of consuming, in random order, a high-fat low-carbohydrate (HFLC) diet and a LFHC diet. Plasma concentrations of Lp(a) (P < 0.01), OxPL/apolipoprotein (apo)B (P < 0.005), and OxPL-apo(a) (P < 0.05) were significantly higher on the LFHC diet compared with the HFLC diet whereas LDL peak particle size was significantly smaller (P < 0.0001). Diet-induced changes in Lp(a) were strongly correlated with changes in OxPL/apoB (P < 0.0001). The increases in plasma Lp(a) levels after the LFHC diet were also correlated with decreases in medium LDL particles (P < 0.01) and increases in very small LDL particles (P < 0.05). These results demonstrate that induction of increased levels of Lp(a) by an LFHC diet is associated with increases in OxPLs and with changes in LDL subclass distribution that may reflect altered metabolism of Lp(a) particles.

Inhibition of arterial lesion progression in CD16-deficient mice: evidence for altered immunity and the role of IL-10

AIMS

Given the importance of IgG Fc receptors in immune regulation, we hypothesized that Fcg receptor type III (FcgRIII, CD16) plays an important role in atherogenesis. We therefore analysed the formation of arterial lesions in LDL receptor-deficient (LDLR(-/-)) and FcgRIII(-/-)xLDLR(-/-) double knockout mice at three different points up to 24 weeks of exposure to a high-fat diet.

METHODS AND RESULTS

Analysis of Oil Red-O-stained sections revealed no difference in lesion formation between strains after 6 weeks of a high-fat diet, and a modest decrease after 14 weeks in double knockouts relative to LDLR(-/-) controls. After 24 weeks, lesion formation was decreased in the aortic root (30%) and innominate artery (50%) in FcgRIII double knockouts relative to LDLR(-/-) controls. Analysis of peripheral CD4+ T-cells by intracellular flow cytometry from double knockouts after 24 weeks of a high-fat diet revealed statistically significant increases in the percentages of cells producing interferon-gamma, interleukin (IL)-10, and IL-4 relative to controls, differences that were also observed by analyses of whole aortas for cytokine mRNA levels. As determined by flow cytometry, FcgRIII deficiency resulted in an expansion of CD4+ cells and an increase in the CD4 to CD8 ratio. Analysis of plasma anti-oxidized LDL (OxLDL) antibodies by chemiluminescent assay revealed that IgG1 and IgG2c titers to OxLDL were increased in FcgRIII (-/-)xLDLR(-/-) double knockouts relative to LDLR(-/-) controls, while total IgG levels were similar.

CONCLUSION

These results reveal altered immunity in FcgRIII(-/-)xLDLR(-/-) mice and a reduction in lesion formation associated with increased production of IL-10 by an expansion of CD4+ T-cells. The reduction in lesion formation was manifest well after evidence of an immune response to OxLDL, suggesting that FcgRIII contributes to lesion progression in murine atherosclerosis.

Systematics of early and middle Miocene Old World monkeys

New information about the early cercopithecoids Prohylobates tandyi (Wadi Moghra, Egypt) and Prohylobates sp. indet. (Buluk and Nabwal, Kenya) is presented. Comparisons are made among all major collections of Early and Middle Miocene catarrhine monkeys, and a systematic revision of the early Old World monkeys is provided. Previous work involving the systematics of early Old World monkeys (Victoriapithecidae; Cercopithecoidea) has been hampered by a number of factors, including the poor preservation of Prohylobates material from North Africa and lack of comparable anatomical parts across collections. However, it is now shown that basal cercopithecoid species from both northern and eastern Africa can be distinguished from one another on the basis of degree of lower molar bilophodonty, relative lower molar size, occlusal details, symphyseal construction, and mandibular shape. Results of particular interest include: 1) the first identification of features that unambiguously define Prohylobates relative to Victoriapithecus; 2) confirmation that P. tandyi is incompletely bilophodont; and 3) recognition of additional victoriapithecid species.

Conventional Dendritic Cells at the Crossroads Between Immunity and Cholesterol Homeostasis in Atherosclerosis

Background— Immunoinflammatory mechanisms are implicated in the atherogenic process. The polarization of the immune response and the nature of the immune cells involved, however, are major determinants of the net effect, which may be either proatherogenic or antiatherogenic. Dendritic cells (DCs) are central to the regulation of immunity, the polarization of the immune response, and the induction of tolerance to antigens. The potential role of DCs in atherosclerosis, however, remains to be defined.

Methods and Results— We created a mouse model in which the lifespan and immunogenicity of conventional DCs are enhanced by specific overexpression of the antiapoptotic gene hBcl-2 under the control of the CD11c promoter. When studied in either low-density lipoprotein receptor–deficient or apolipoprotein E–deficient backgrounds, DC-hBcl2 mice exhibited an expanded DC population associated with enhanced T-cell activation, a T-helper 1 and T-helper 17 cytokine expression profile, and elevated production of T-helper 1–driven IgG2c autoantibodies directed against oxidation-specific epitopes. This proatherogenic signature, however, was not associated with acceleration of atherosclerotic plaque progression, because expansion of the DC population was unexpectedly associated with an atheroprotective decrease in plasma cholesterol levels. Conversely, depletion of DCs in hyperlipidemic CD11c–diphtheria toxin receptor/apolipoprotein E–deficient transgenic mice resulted in enhanced cholesterolemia, thereby arguing for a close relationship between the DC population and plasma cholesterol levels.

Conclusions— Considered together, the present data reveal that conventional DCs are central to the atherosclerotic process, because they are directly implicated in both cholesterol homeostasis and the immune response.

Markers and risk factors for HCV, HBV and HIV in a network of injecting drug users in Melbourne, Australia

BACKGROUND AND AIMS

Current injecting drug users (IDU) in major street drug markets within greater Melbourne were recruited to a longitudinal study on blood borne viruses. Here we investigated risk factors for hepatitis C virus (HCV), hepatitis B virus (HBV) and HIV infection in these IDU at the time of their recruitment.

METHODS

Three hundred and eighty-two IDU completed detailed questionnaires on their drug use and risk behaviours, and provided blood samples for serology testing. These data were analysed using univariate and multivariate techniques.

RESULTS

The overall prevalence of exposure to HCV, HBV and HIV was estimated at 70%, 34% and <1%, respectively. Independent predictors of HCV exposure were history of imprisonment (RR 1.34, 95% CI 1.19-1.52), use of someone else's needle or syringe (RR 1.23, 95% CI 1.07-1.42), >7.6years length of time injecting (RR 1.21, 95% CI 1.07-1.37), and originating from Vietnam (RR 1.12, 95% CI 1.07-1.18). Independent predictors of HBV exposure were HCV exposure (RR 2.15, 95% CI 1.35-3.43), >7.6years length of time injecting (RR 1.57, 95% CI 1.17-2.13) and originating from outside Australia (RR 1.60, 95% CI 1.22-2.10). Neither prison- nor community-applied tattoos predicted HCV or HBV exposure. Up to 31% of IDU who injected for 1year or less were HCV antibody positive, as were 53% of those who injected for 2years or less.

CONCLUSIONS

Ongoing engagement with young IDU, through the provision of harm reduction education and resources, is critical if we are to address blood borne viral infections and other health and social harms associated with injecting drug use.

Macrophage apoptosis exerts divergent effects on atherogenesis as a function of lesion stage

BACKGROUND

Because apoptotic cell clearance appears to be defective in advanced compared with early atherosclerotic plaques, macrophage apoptosis may differentially affect plaque progression as a function of lesion stage.

METHODS AND RESULTS

We first evaluated the impact of targeted protection of macrophages against apoptosis at both early and advanced stages of atherosclerosis. Increased resistance of macrophages to apoptosis in early atherosclerotic lesions was associated with increased plaque burden; in contrast, it afforded protection against progression to advanced lesions. Conversely, sustained induction of apoptosis in lesional macrophages of advanced lesions resulted in a significant increase in lesion size. Such enhanced lesion size occurred as a result not only of apoptotic cell accumulation but also of elevated chemokine expression and subsequent intimal recruitment of circulating monocytes.

CONCLUSIONS

Considered together, our data suggest that macrophage apoptosis is atheroprotective in fatty streak lesions, but in contrast, defective clearance of apoptotic debris in advanced lesions favors arterial wall inflammation and enhanced recruitment of monocytes, leading to enhanced atherogenesis.

Relationship of oxidized phospholipids on apolipoprotein B-100 particles to race/ethnicity, apolipoprotein(a) isoform size, and cardiovascular risk factors: results from the Dallas Heart Study

BACKGROUND

Elevated levels of oxidized phospholipids (OxPLs) on apolipoprotein B-100 particles (OxPL/apoB) are associated with cardiovascular disease and predict new cardiovascular events. Elevated lipoprotein (a) [Lp(a)] levels are a risk factor for cardiovascular disease in whites and also in blacks if they carry small apolipoprotein(a) [apo(a)] isoforms. The relationship of OxPL/apoB levels to race/ethnicity, cardiovascular risk factors, and apo(a) isoforms is not established.

METHODS AND RESULTS

OxPL/apoB levels were measured in 3481 subjects (1831 black, 1047 white, and 603 Hispanic subjects) in the Dallas Heart Study and correlated with age, sex, cardiovascular risk factors, and Lp(a) and apo(a) isoforms. Significant differences in OxPL/apoB levels were noted among racial/ethnic subgroups, with blacks having the highest levels compared with whites and Hispanics (P<0.001 for each comparison). OxPL/apoB levels generally did not correlate with age, sex, or risk factors. In the overall cohort, OxPL/apoB levels strongly correlated with Lp(a) (r=0.85, P<0.001), with the shape of the relationship demonstrating a "reverse L" shape for log-transformed values. The highest correlation was present in blacks, followed by whites and Hispanics; was dependent on apo(a) isoform size; and became progressively weaker with larger isoforms. The size of the major apo(a) isoform (number of kringle type IV repeats) was negatively associated with OxPL/apoB (r=-0.49, P<0.001) and Lp(a) (r=-0.61, P<0.001) regardless of racial/ethnic group. After adjustment for apo(a) isoform size, the relationship between OxPL/apoB and Lp(a) remained significant (r=0.67, P<0.001).

CONCLUSIONS

OxPL/apoB levels vary according to race/ethnicity, are largely independent of cardiovascular risk factors, and are inversely associated with apo(a) isoform size. The association of OxPL with small apo(a) isoforms, in which a similar relationship is present among all racial/ethnic subgroups despite differences in Lp(a) levels, may be a key determinant of cardiovascular risk.

Vascular lipid accumulation, lipoprotein oxidation, and macrophage lipid uptake in hypercholesterolemic zebrafish

Lipid accumulation in arteries induces vascular inflammation and atherosclerosis, the major cause of heart attack and stroke in humans. Extreme hyperlipidemia induced in mice and rabbits enables modeling many aspects of human atherosclerosis, but microscopic examination of plaques is possible only postmortem. Here we report that feeding adult zebrafish (Danio rerio) a high-cholesterol diet (HCD) resulted in hypercholesterolemia, remarkable lipoprotein oxidation, and fatty streak formation in the arteries. Feeding an HCD supplemented with a fluorescent cholesteryl ester to optically transparent fli1:EGFP zebrafish larvae in which endothelial cells express green fluorescent protein (GFP), and using confocal microscopy enabled monitoring vascular lipid accumulation and the endothelial cell layer disorganization and thickening in a live animal. The HCD feeding also increased leakage of a fluorescent dextran from the blood vessels. Administering ezetimibe significantly diminished the HCD-induced endothelial cell layer thickening and improved its barrier function. Feeding HCD to lyz:DsRed2 larvae in which macrophages and granulocytes express DsRed resulted in the accumulation of fluorescent myeloid cells in the vascular wall. Using a fluorogenic substrate for phospholipase A(2) (PLA(2)), we observed an increased vascular PLA(2) activity in live HCD-fed larvae compared to control larvae. Furthermore, by transplanting genetically modified murine cells into HCD-fed larvae, we demonstrated that toll-like receptor-4 was required for efficient in vivo lipid uptake by macrophages. These results suggest that the novel zebrafish model is suitable for studying temporal characteristics of certain inflammatory processes of early atherogenesis and the in vivo function of vascular cells.

Correlates of N-terminal prohormone brain natriuretic peptides in African Americans with hypertensive chronic kidney disease: the African American Study of Kidney Disease and Hypertension

BACKGROUND/AIMS

The N-amino-terminal fragment of the prohormone B-type natriuretic peptide (NT-proBNP) is a marker of cardiac stress and elevated levels are indicative of heart failure. Few correlates of NT-proBNP levels have been identified in persons with moderate chronic kidney disease (CKD), and data from those without heart failure and from African Americans are especially limited.

METHODS

The African American Study of Kidney Disease and Hypertension (AASK) enrolled nondiabetic African Americans with hypertensive kidney disease (glomerular filtration rate [GFR] = 20-65 ml/min/1.73 m(2)) and no evidence of clinical heart failure. NT-proBNP was measured in 982 AASK participants.

RESULTS

In unadjusted analyses, GFR (r = -0.39; p < 0.001), hematocrit (r = -0.21; p < 0.001) and body mass index (BMI; r = -0.07; p = 0.04) were inversely correlated, and systolic blood pressure (r = 0.30; p < 0.001) and log UPCR (r = 0.32; p < 0.001) were positively correlated with log NT-proBNP levels. After adjustment for potential confounders, lower GFR and hematocrit and higher systolic blood pressure and protein:creatinine ratio remained significantly associated with higher NT-proBNP.

CONCLUSION

Lower GFR and hematocrit, and higher urinary protein excretion may be associated with volume expansion in CKD. These results suggest that these processes are associated with increased NT-proBNP in CKD and may play a role in the development of heart failure.

Antisense oligonucleotide directed to human apolipoprotein B-100 reduces lipoprotein(a) levels and oxidized phospholipids on human apolipoprotein B-100 particles in lipoprotein(a) transgenic mice

BACKGROUND

Lipoprotein (a) [Lp(a)] is a genetic cardiovascular risk factor that preferentially binds oxidized phospholipids (OxPL) in plasma. There is a lack of therapeutic agents that reduce plasma Lp(a) levels.

METHODS AND RESULTS

Transgenic mice overexpressing human apolipoprotein B-100 (h-apoB-100 [h-apoB mice]) or h-apoB-100 plus human apo(a) to generate genuine Lp(a) particles [Lp(a) mice] were treated with the antisense oligonucleotide mipomersen directed to h-apoB-100 mRNA or control antisense oligonucleotide for 11 weeks by intraperitoneal injection. Mice were then followed up for an additional 10 weeks off therapy. Lp(a) levels [apo(a) bound to apoB-100] and apo(a) levels ["free" apo(a) plus apo(a) bound to apoB-100] were measured by chemiluminescent enzyme-linked immunoassay and commercial assays, respectively. The content of OxPL on h-apoB-100 particles (OxPL/h-apoB) was measured by capturing h-apoB-100 in microtiter wells and detecting OxPL by antibody E06. As expected, mipomersen significantly reduced plasma h-apoB-100 levels in both groups of mice. In Lp(a) mice, mipomersen significantly reduced Lp(a) levels by approximately 75% compared with baseline (P<0.0001) but had no effect on apo(a) levels or hepatic apo(a) mRNA expression. OxPL/h-apoB levels were much higher at baseline in Lp(a) mice compared with h-ApoB mice (P<0.0001) but decreased in a time-dependent fashion with mipomersen. There was no effect of the control antisense oligonucleotide on lipoprotein levels or oxidative parameters.

CONCLUSIONS

Mipomersen significantly reduced Lp(a) and OxPL/apoB levels in Lp(a) mice. The present study demonstrates that h-apoB-100 is a limiting factor in Lp(a) particle synthesis in this Lp(a) transgenic model. If applicable to humans, mipomersen may represent a novel therapeutic approach to reducing Lp(a) levels and their associated OxPL.

A novel function of lipoprotein [a] as a preferential carrier of oxidized phospholipids in human plasma

Oxidized phospholipids (OxPLs) on apolipoprotein B-100 (apoB-100) particles are strongly associated with lipoprotein [a] (Lp[a]). In this study, we evaluated whether Lp[a] is preferentially the carrier of OxPL in human plasma. The content of OxPL on apoB-100 particles was measured with monoclonal antibody E06, which recognizes the phosphocholine (PC) headgroup of oxidized but not native phospholipids. To assess whether OxPLs were preferentially bound by Lp[a] as opposed to other lipoproteins, immunoprecipitation and ultracentrifugation experiments, in vitro transfer studies, and chemiluminescent ELISAs were performed. Immunoprecipitation of Lp[a] from human plasma with an apolipoprotein [a] (apo[a])-specific antibody demonstrated that more than 85% of E06 reactivity (i.e., OxPL) coimmunoprecipitated with Lp[a]. Ultracentrifugation experiments showed that nearly all OxPLs were found in fractions containing apo[a], as opposed to other apolipoproteins. In vitro transfer studies showed that oxidized LDL preferentially donates OxPLs to Lp[a], as opposed to LDL, in a time- and temperature-dependent manner, even in aqueous buffer. Approximately 50% of E06 immunoreactivity could be extracted from isolated Lp[a] following exposure of plasma to various lipid solvents. These data demonstrate that Lp[a] is the preferential carrier of PC-containing OxPL in human plasma. This unique property of Lp[a] suggests novel insights into its physiological function and mechanisms of atherogenicity.

Oxidized Low-Density Lipoprotein Biomarkers in Patients with End-Stage Renal Failure: Acute Effects of Hemodialysis

<i>Objective:</i> To assess the effect of end-stage renal failure on oxidized low-density lipoprotein (OxLDL) biomarkers and the acute effects of hemodialysis. Oxidized phospholipids (OxPL) on apolipoprotein B-100 (apoB) particles (OxPL/apoB) have been associated with cardiovascular disease and new cardiovascular events. Patients with end-stage renal failure have increased oxidative stress and are at significantly increased risk of cardiovascular disease. <i>Methods and Results:</i> Fifty-two stable patients with end-stage renal failure undergoing chronic hemodialysis were included in the study. Pre and post hemodialysis blood samples were obtained for measurement of OxLDL biomarkers: oxidized phospholipids (OxPL) on apolipoprotein B-100 (apoB) particles (OxPL/apoB) measured by antibody E06, IgG and IgM autoantibody titers to copper-oxidized LDL (Cu-OxLDL) and malondialdehyde (MDA)-LDL, IgG and IgM apolipoprotein B-100-immune complexes (IC/apoB). Traditional laboratory variables as well as C-reactive protein (CRP) and lipoprotein(a) [Lp(a)] were also measured. For the baseline variables, the distribution of OxPL/apoB and Lp(a) were skewed to lower values, and a strong correlation was noted between OxPL/apoB and Lp(a) (r = 0.94, p < 0.0001). No major associations were noted between OxLDL biomarkers and age, gender or dialytic age. There were also no correlations between OxLDL biomarkers and traditional risk factors, CRP, body mass index, serum creatinine, hypertension or intravenous iron therapy. Following dialysis, there as a significant reduction in OxPL/apoB (–7.5%, p = 0.048) and triglyceride levels (–10.8%, p = 0.005). All other OxLDL biomarkers, CRP, total cholesterol, LDL-C, HDL-C and apoB-100 increased significantly (range 6.3–26.9%, p value range 0.005 to <0.0001). Total protein plasma levels increased 8.8% (p = 0.014 compared to predialysis) following dialysis, consistent with a hemoconcentration effect of hemodialysis. <i>Conclusion:</i> In end-stage renal failure patients undergoing hemodialysis, a reduction in OxPL/apoB levels was noted, despite the hemoconcentrating and strong pro-oxidant milieu of hemodialysis. Studies in larger populations of end-stage renal failure patients are needed to assess whether these findings predict future clinical outcomes.

Increased Plasma Oxidized Phospholipid:Apolipoprotein B-100 Ratio With Concomitant Depletion of Oxidized Phospholipids From Atherosclerotic Lesions After Dietary Lipid-Lowering

Background— Oxidized phospholipids (OxPL) are pro-inflammatory. We evaluated whether changes in plasma levels of OxPL associated with apolipoprotein B-100 (apoB-100) reflect changes in OxPL content in atherosclerotic plaques during dietary-induced atherosclerosis progression and regression.

Methods and Results— OxPL content was measured in plasma and immunohistochemically in aortic plaques with antibody E06 in cynomolgus monkeys and New Zealand White rabbits at baseline, after a high-fat/high-cholesterol diet and after reversion to normal chow. The OxPL/apoB ratio, representing the content of OxPL on individual apoB-100 particles, and Total apoB-OxPL (OxPL/apoB multiplied by plasma apoB levels), reflecting the OxPL content on all apoB-100 particles, were measured. Total apoB-OxPL plasma levels increased 3-fold ( P <0.0001) during hypercholesterolemia and decreased ≈75% ( P <0.0001) during reversion to normocholesterolemia. In contrast, OxPL/apoB levels decreased significantly ( P <0.0001) during hypercholesterolemia and increased significantly ( P =0.0002) during reversion to normocholesterolemia. Immunostaining revealed that during atherosclerosis progression OxPL co-localized with apoB-100, whereas during regression OxPL virtually disappeared.

Conclusion— In the setting of overall reduction of plasma OxPL levels after dietary lipid-lowering, increases in the OxPL/apoB ratio reflect reduced content of OxPL in atherosclerotic plaques. These data suggest that changes in the OxPL/apoB ratio may reflect early atherosclerosis regression.

Relationship of IgG and IgM autoantibodies to oxidized low density lipoprotein with coronary artery disease and cardiovascular events

The relationship between autoantibodies to oxidized low density lipoprotein (OxLDL) and coronary artery disease (CAD) remains controversial. IgM and IgG OxLDL autoantibodies to malondialdehyde (MDA)-modified LDL, copper oxidized low density lipoprotein (CuOxLDL), and oxidized cholesterol linoleate (OxCL), as well as apolipoprotein B-100 immune complexes (apoB-ICs), were measured in 504 patients undergoing clinically indicated coronary angiography. Patients were followed for cardiovascular events for a median of 4 years. In univariate analysis, IgM OxLDL autoantibodies and IgM apoB-ICs were inversely associated with the presence of angiographically determined CAD, whereas IgG OxLDL autoantibodies and IgG apoB-ICs were positively associated. In logistic regression analysis, compared with the first quartile, patients in the fourth quartile of IgM OxLDL autoantibodies and apoB-ICs showed a lower probability of angiographically determined CAD (>50% diameter stenosis). Odds ratios and (95% confidence intervals) were as follows: MDA-LDL, 0.51 (0.32-0.82; P = 0.005); CuOxLDL, 0.63 (0.39-1.01; P = 0.05); OxCL, 0.63 (0.39-1.01; P = 0.05); and apoB-IC, 0.55 (0.34-0.88; P = 0.013). These relationships were accentuated in the setting of hypercholesterolemia, with the highest IgM levels showing the lowest risk of CAD for the same level of hypercholesterolemia. Multivariable analysis revealed that neither IgM or IgG OxLDL autoantibodies nor apoB-ICs were independently associated with angiographically determined CAD or cardiovascular events. In conclusion, IgG and IgM OxLDL biomarkers have divergent associations with CAD in univariate analysis but are not independent predictors of CAD or clinical events.

One year follow-up of overweight and obese hypertensive adults following intensive lifestyle therapy

OBJECTIVE

To examine the long-term effect on weight maintenance and dietary habits of participants in a clinical trial for weight loss.

SETTING

Community-based residents living in Maryland.

PARTICIPANTS

Forty-four hypertensive, overweight adults who participated in a randomized clinical trial of weight loss. Participants were randomized to an intensive 'lifestyle' intervention or a 'monitoring' group.

MAIN OUTCOME MEASURES

Weight, self-reported current intake of fat and fruit/fibre and self-reported barriers to maintain weight loss were assessed 1 year after the completion of the Diet, Exercise and Weight-loss Intervention Trial (DEW-IT) trial.

ANALYSIS

t-tests were used to compare groups for differences in continuous variables and chi-square tests were used to compare groups for categorical variables.

RESULTS

Fourty-two of the 44 DEW-IT subjects participated in the follow-up study. Overall, 55% (12/19) of the lifestyle intervention group remained at or below their baseline weight at 1 year, compared with 48% (11/23) of the monitoring group (P = 0.32). However, during that year, 95% (18/19) of the lifestyle intervention group and 52% (12/23) of the monitoring group gained weight from the end of the study. Both groups reported similar intake of fruits/vegetables (servings day(-1)), dietary fibre (g day(-1)) and fat (g day(-1)).

CONCLUSIONS AND IMPLICATIONS

The majority of participants who lost weight during the trial regained weight during the course of 1 year. A successful intensive 2-month programme of lifestyle modification (DEW-IT) was ineffective for long-term maintenance of weight loss.

From disorder to order in marching locusts

Recent models from theoretical physics have predicted that mass-migrating animal groups may share group-level properties, irrespective of the type of animals in the group. One key prediction is that as the density of animals in the group increases, a rapid transition occurs from disordered movement of individuals within the group to highly aligned collective motion. Understanding such a transition is crucial to the control of mobile swarming insect pests such as the desert locust. We confirmed the prediction of a rapid transition from disordered to ordered movement and identified a critical density for the onset of coordinated marching in locust nymphs. We also demonstrated a dynamic instability in motion at densities typical of locusts in the field, in which groups can switch direction without external perturbation, potentially facilitating the rapid transfer of directional information.

Oxidized Phospholipids Predict the Presence and Progression of Carotid and Femoral Atherosclerosis and Symptomatic Cardiovascular Disease

OBJECTIVES

The purpose of this work was to determine the predictive value of oxidized phospholipids (OxPLs) present on apolipoprotein B-100 particles (apoB) in carotid and femoral atherosclerosis.

BACKGROUND

The OxPLs are pro-inflammatory and pro-atherogenic and may be detected using the antibody E06 (OxPL/apoB).

METHODS

The Bruneck study is a prospective population-based survey of 40- to 79-year-old men and women initiated in 1990. Plasma levels of OxPL/apoB and lipoprotein (a) [Lp(a)] were measured in 765 of 826 (92.6%) and 671 of 684 (98.1%) subjects alive in 1995 and 2000, respectively, and correlated with ultrasound measures of carotid and femoral atherosclerosis.

RESULTS

The distribution of the OxPL/apoB levels was skewed to lower levels and nearly identical to Lp(a) levels. The OxPL/apoB and Lp(a) levels were highly correlated (r = 0.87, p < 0.001), and displayed long-term stability and lacked correlations with most cardiovascular risk factors and lifestyle variables. The number of apolipoprotein (a) kringle IV-2 repeats was inversely related to Lp(a) mass (r = -0.48, p < 0.001) and OxPL/apoB levels (r = -0.46, p < 0.001). In multivariable analysis, OxPL/apoB levels were strongly and significantly associated with the presence, extent, and development (1995 to 2000) of carotid and femoral atherosclerosis and predicted the presence of symptomatic cardiovascular disease. Both OxPL/apoB and Lp(a) levels showed similar associations with atherosclerosis severity and progression, suggesting a common biological influence on atherogenesis.

CONCLUSIONS

This study suggests that pro-inflammatory oxidized phospholipids, present primarily on Lp(a), are significant predictors of the presence and extent of carotid and femoral atherosclerosis, development of new lesions, and increased risk of cardiovascular events. The OxPL biomarkers may provide valuable insights into diagnosing and monitoring cardiovascular disease.

Oxidized Low-Density Lipoprotein in Children With Familial Hypercholesterolemia and Unaffected Siblings

OBJECTIVES

To assess the role of oxidized phospholipids (OxPLs) in children with familial hypercholesterolemia (FH) and the effect of pravastatin.

BACKGROUND

Oxidized phospholipids are a major component of oxidized low-density lipoprotein (OxLDL) and are bound to lipoprotein (a) [Lp(a)]. The significance of OxPL markers in children is unknown.

METHODS

Children with FH were randomized to placebo (n = 88) or pravastatin (n = 90) after instruction on American Heart Association step II diet. Unaffected siblings (n = 78) served as controls. The OxPL content on apolipoprotein B-100 (apoB) detected by antibody E06 (OxPL/apoB ratio), immunoglobulin (Ig)G and IgM immune complexes per apoB (IC/apoB) and on all apoB particles (total apoB-IC = IC/apoB multiplied by plasma apoB levels), autoantibodies to malondialdehyde (MDA)-low-density lipoprotein (LDL), Lp(a), and apoB levels were measured at baseline and after two years of treatment.

RESULTS

Compared with unaffected siblings, children with FH had significantly lower levels of OxPL/apoB but higher levels of IgG and IgM total apoB-IC and IgM MDA-LDL autoantibodies. From baseline to two-year follow-up, compared with placebo pravastatin treatment resulted in a greater mean percentage change in apoB (-18.7% vs. 0.3%; p = 0.001), total IgG apoB-IC (-31.9% vs. -12.2%; p < 0.001), and total IgM apoB-IC (-25.5% vs. 13.2%; p = 0.001). Interestingly, pravastatin also resulted in higher OxPL/apoB (48.7% vs. 29.3%; p = 0.028) and Lp(a) levels (21.9% vs. 10.7%; p = 0.044).

CONCLUSIONS

Compared with unaffected siblings, children with FH are characterized by elevated levels of apoB-IC and IgM MDA-LDL autoantibodies. Compared with placebo, pravastatin led to a greater reduction in apoB-IC but also to a greater increase in OxPL/apoB and Lp(a), which may represent a novel mechanism of mobilization and clearance of OxPL.

The prevalence of HCV antibody in South Australian prisoners

OBJECTIVES

The study was aimed at identifying the hepatitis C virus (HCV)-antibody status of prisoners incarcerated in South Australia in order to develop an HCV prevalence estimate for the whole prison system.

METHODS

The health records of persons incarcerated within eight prisons (accommodating approximately 93% of the jurisdiction's adult incarcerated population) were audited for evidence of HCV infection, age, sex, Indigenous status (Australian Aboriginal or Torres Strait Islander) and date of entry to prison. These data were analysed using both univariate and multivariate techniques.

RESULTS

Among 1347 prisoners (1254 males and 93 females), 30.2% were HCV-antibody positive. After excluding those with no history of testing, HCV-antibody prevalence rose to 41.3% (males 39.8%, females 66.1%). HCV-antibody positivity was significantly associated with age, sex and Indigenous status in both univariate and multivariate analyses.

CONCLUSIONS

Consistent with the literature, the prevalence of HCV infection in the SA prison system appears to be extremely high. This study suggests that HCV prevention efforts in prison settings should be considered as an important priority.

Broiler responsiveness (Ross x 708) to diets varying in amino acid density

Sex-separate male and female broilers (2,592 broilers; Ross x 708) were placed in 144 floor pens (12 replications per treatment) and fed diets containing high (H) and moderate (M) amino acid density from 1 to 55 d of age. Diets were formulated using ileal digestible amino acid ratios to Lys. Six dietary treatment combinations (MMMMM, HMMMM, HHMMM, HHHMM, HHHHM, and HHHHH) were implemented in 5 diet phases (1 to 5, 6 to 14, 15 to 35, 36 to 45, and 46 to 55 d of age). Male birds were heavier (P < or = 0.05) and had lower (P < or = 0.05) feed conversion, abdominal fat, and breast yield than female birds. Birds fed H diets in the first 3 phases had optimal (P < or = 0.05) BW and feed conversion (d 35, and 45), but optimal (P < or = 0.05) feed conversion at d 55 warranted H diets in all phases. Breast meat (d 35) and carcass (d 55) relative to BW were highest (P < or = 0.05) in birds fed H diets in the first 3 phases; however, differences in 55 d breast meat yield did not occur. Results indicate that amino acid needs of Ross x 708 broilers are most critical from 1 to 35 d of age. Predicted economic margins were advantageous in birds fed H diets resulting in dollar 0.12 and dollar 0.05/bird more income over feed costs at 35 and 55 d, respectively, in comparison with birds fed M diets.

Oxidized phospholipids, Lp(a) lipoprotein, and coronary artery disease

BACKGROUND

Lp(a) lipoprotein binds proinflammatory oxidized phospholipids. We investigated whether levels of oxidized low-density lipoprotein (LDL) measured with use of monoclonal antibody E06 reflect the presence and extent of obstructive coronary artery disease, defined as a stenosis of more than 50 percent of the luminal diameter.

METHODS

Levels of oxidized LDL and Lp(a) lipoprotein were measured in a total of 504 patients immediately before coronary angiography. Levels of oxidized LDL are reported as the oxidized phospholipid content per particle of apolipoprotein B-100 (oxidized phospholipid:apo B-100 ratio).

RESULTS

Measurements of the oxidized phospholipid:apo B-100 ratio and Lp(a) lipoprotein levels were skewed toward lower values, and the values for the oxidized phospholipid:apo B-100 ratio correlated strongly with those for Lp(a) lipoprotein (r=0.83, P<0.001). In the entire cohort, the oxidized phospholipid:apo B-100 ratio and Lp(a) lipoprotein levels showed a strong and graded association with the presence and extent of coronary artery disease (i.e., the number of vessels with a stenosis of more than 50 percent of the luminal diameter) (P<0.001). Among patients 60 years of age or younger, those in the highest quartiles for the oxidized phospholipid:apo B-100 ratio and Lp(a) lipoprotein levels had odds ratios for coronary artery disease of 3.12 (P<0.001) and 3.64 (P<0.001), respectively, as compared with patients in the lowest quartile. The combined effect of hypercholesterolemia and being in the highest quartiles of the oxidized phospholipid:apo B-100 ratio (odds ratio, 16.8; P<0.001) and Lp(a) lipoprotein levels (odds ratio, 14.2; P<0.001) significantly increased the probability of coronary artery disease among patients 60 years of age or younger. In the entire study group, the association of the oxidized phospholipid:apo B-100 ratio with obstructive coronary artery disease was independent of all clinical and lipid measures except one, Lp(a) lipoprotein. However, among patients 60 years of age or younger, the oxidized phospholipid:apo B-100 ratio remained an independent predictor of coronary artery disease.

CONCLUSIONS

Circulating levels of oxidized LDL are strongly associated with angiographically documented coronary artery disease, particularly in patients 60 years of age or younger. These data suggest that the atherogenicity of Lp(a) lipoprotein may be mediated in part by associated proinflammatory oxidized phospholipids.

Local Expression of Platelet-Activating Factor-Acetylhydrolase Reduces Accumulation of Oxidized Lipoproteins and Inhibits Inflammation, Shear Stress-Induced Thrombosis, and Neointima Formation in Balloon-Injured Carotid Arteries in Nonhyperlipidemic Rabbits

Background— Platelet-activating factor (PAF) and PAF-like phospholipids are inactivated by PAF-acetylhydrolase (PAF-AH). Using nonhyperlipidemic animals, we tested whether local expression of PAF-AH into injured arteries might induce antithrombotic and antiinflammatory effects.

Method and Results— Balloon-injured rabbit carotid arteries were infected at the time of injury with an adenovirus expressing either human plasma PAF-AH (AdPAF-AH) or bacterial β-galactosidase (AdLacZ) or infused with saline. Seven days later, shear stress-induced thrombosis was observed in all AdLacZ-infected and saline-infused arteries (controls) but eliminated in AdPAF-AH-treated contralateral arteries, even in the presence of epinephrine or an inhibitor of NO production. Injury-induced expression of tissue factor was also significantly suppressed. In AdPAF-AH-treated arteries compared with controls, the expressions of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 and macrophage infiltration were decreased by 66%, 66%, and 71%, respectively ( P <0.01), and intimal area and intima/media ratio were decreased on day 21 by 43% and 52%, respectively ( P <0.05). Within 1 week after injury, oxidized lipoproteins (OxLDL) had readily accumulated in the arterial wall. However, this was markedly reduced in the AdPAF-AH-treated arteries. No differences in the titers of autoantibodies to OxLDL or total cholesterol in blood were found between controls and AdPAF-AH-treated rabbits.

Conclusions— Our results show for the first time that OxLDL accumulates in arteries in nonhyperlipidemic animals within 1 week after injury and that local expression of PAF-AH reduces this accumulation and exerts antiinflammatory, antithrombotic, and antiproliferative effects without changing the plasma levels of PAF-AH activity or titers of autoantibodies to OxLDL.

High-level lipoprotein [a] expression in transgenic mice: evidence for oxidized phospholipids in lipoprotein [a] but not in low density lipoproteins

Efforts to elucidate the role of lipoprotein [a] (Lp[a]) in atherogenesis have been hampered by the lack of an animal model with high plasma Lp[a] levels. We produced two lines of transgenic mice expressing apolipoprotein [a] (apo[a]) in the liver and crossed them with mice expressing human apolipoprotein B-100 (apoB-100), generating two lines of Lp[a] mice. One had Lp[a] levels of approximately 700 mg/dl, well above the 30 mg/dl threshold associated with increased risk of atherosclerosis in humans; the other had levels of approximately 35 mg/dl. Most of the LDL in mice with high-level apo[a] expression was covalently bound to apo[a], but most of the LDL in the low-expressing line was free. Using an enzyme-linked sandwich assay with monoclonal antibody EO6, we found high levels of oxidized phospholipids in Lp[a] from high-expressing mice but not in LDL from low-expressing mice or in LDL from human apoB-100 transgenic mice (P <0.00001), even though all mice had similar plasma levels of human apoB-100. The increase in oxidized lipids specific to Lp[a] in high-level apo[a]-expressing mice suggests a mechanism by which increased circulating levels of Lp[a] could contribute to atherogenesis.

Alterations in plasma vitamin E distribution in type 2 diabetic patients with elevated plasma phospholipid transfer protein activity

Mouse studies indicated that plasma phospholipid transfer protein (PLTP) determines the plasma distribution of vitamin E, a potent lipophilic antioxidant. Vitamin E distribution, antioxidant status, and titer of anti-oxidized LDLs (oxLDL) autoantibodies were evaluated in plasma from control subjects (n = 31) and type 2 diabetic patients (n = 31) with elevated plasma PLTP concentration. Unlike diabetic and control HDLs, which displayed similar vitamin E contents, diabetic VLDLs and diabetic LDLs contained fewer vitamin E molecules than normal counterparts. Plasma PLTP concentration in diabetic plasmas correlated negatively with vitamin E in VLDL+LDL, but positively with vitamin E in HDL, with an even stronger correlation with the VLDL+LDL-to-HDL vitamin E ratio. Circulating levels of oxLDL were significantly higher in diabetic plasmas than in control plasmas. Whereas the titer of IgG autoantibodies to modified LDL did not differ significantly between diabetic patients and control subjects, diabetic plasmas showed significantly lower levels of potentially protective IgM autoantibodies. The present observations support a pathophysiological role of PLTP in decreasing the vitamin E content of apolipoprotein B-containing lipoproteins, but not of HDL in plasma of type 2 diabetic patients, contributing to a greater potential for LDL oxidation.

High-Dose Atorvastatin Reduces Total Plasma Levels of Oxidized Phospholipids and Immune Complexes Present on Apolipoprotein B-100 in Patients With Acute Coronary Syndromes in the MIRACL Trial

BACKGROUND

Oxidized phospholipids (OxPL) are present within atherosclerotic plaques and bound by lipoprotein (a) [Lp(a)] in plasma. This study evaluated the impact of atorvastatin on oxidized LDL (OxLDL) in patients with acute coronary syndromes (ACS).

METHODS AND RESULTS

OxLDL-E06 (OxPL content on apolipoprotein B-100 [apoB] detected by antibody E06), apoB-100 immune complexes (apoB-IC), OxLDL autoantibodies, and Lp(a) levels were measured in 2341 patients at baseline and after 16 weeks of treatment with atorvastatin 80 mg/d or placebo. The OxLDL-E06 and apoB-IC data are reported per apoB-100 particle (OxPL/apoB, IC/apoB) and as total levels on all apoB-100 particles (total apoB-OxPL and total apoB-IC [eg, OxPL/apoB or IC/apoBxapoB-100 levels]). Compared with baseline values, atorvastatin reduced apoB-100 (-33%), total apoB-OxPL (-29.7%), total apoB-IC IgG (-29.5%), and IgM (-25.7%) (P<0.0001 for all), whereas no change or an increase was observed with placebo. When normalized per apoB-100, compared with placebo, atorvastatin increased OxPL/apoB (9.5% versus -3.9%, P<0.0001) and Lp(a) (8.8% versus -0.7%, (P<0.0001). A strong correlation was noted between OxPL/apoB and Lp(a) (R=0.85, P<0.0001), consistent with previous data that Lp(a) binds OxPL.

CONCLUSIONS

After atorvastatin treatment, total OxPL on all apoB-100 particles was decreased. However, there was enrichment of OxPL on a smaller pool of apoB-100 particles, in parallel with similar increases in Lp(a), suggesting binding by Lp(a). These data support the hypothesis that atorvastatin promotes mobilization and clearance of proinflammatory OxPL, which may contribute to a reduction in ischemic events after ACS.

Autoantibodies to OxLDL fail to alter the clearance of injected OxLDL in apolipoprotein E-deficient mice

This study tests the hypothesis that autoantibodies to oxidation epitopes on oxidized LDL (OxLDL) promote the clearance of OxLDL from the plasma. Human LDL (hLDL) was injected into immune-competent apolipoprotein E-deficient (apoE(-/-)) mice and immune-deficient apoE(-/-)/recombination-activating gene-deficient mice that lack mature T and B cells and thus antibodies. There was a progressive decrease in human apoB-100 in the plasma in all mice, but the rate of clearance was not greater in the immune-competent mice than in the immune-deficient mice. Interestingly, oxidized phospholipid (OxPL) epitopes as detected by the EO6 antibody on the hLDL increased over time, suggesting de novo oxidation of the LDL or transfer of OxPL to the particles. Because the native LDL was not extensively modified, we also examined the clearance of copper OxLDL. Although the extensively OxLDL was cleared faster than the native LDL, there was no difference in the rate of clearance as a function of immune status. There appeared to be some transfer of OxPL to the endogenous murine LDL. Together, these results suggest that oxidation-specific antibodies do not participate to any great extent in the clearance of OxLDL from plasma. However, it is possible that such antibodies may bind to oxidation epitopes and modulate lesion formation within the vessel wall.

Percutaneous coronary intervention results in acute increases in oxidized phospholipids and lipoprotein(a): short-term and long-term immunologic responses to oxidized low-density lipoprotein

BACKGROUND

This study was performed to assess whether oxidized low-density lipoprotein (OxLDL) levels are elevated after percutaneous coronary intervention (PCI).

METHODS AND RESULTS

Patients (n=141) with stable angina pectoris undergoing PCI had serial venous blood samples drawn before PCI, after PCI, and at 6 and 24 hours, 3 days, 1 week, and 1, 3, and 6 months. Plasma levels of OxLDL-E06, a measure of oxidized phospholipid (OxPL) content on apolipoprotein B-100 detected by antibody E06, lipoprotein(a) [Lp(a)], autoantibodies to malondialdehyde (MDA)-LDL and copper-oxidized LDL (Cu-OxLDL), and apolipoprotein B-100-immune complexes (apoB-IC) were measured. OxLDL-E06 and Lp(a) levels significantly increased immediately after PCI by 36% (P<0.0001) and 64% (P<0.0001), respectively, and returned to baseline by 6 hours. In vitro immunoprecipitation of Lp(a) from selected plasma samples showed that almost all of the OxPL detected by E06 was bound to Lp(a) at all time points, except in the post-PCI sample, suggesting independent release and subsequent reassociation of OxPL with Lp(a) by 6 hours. Strong correlations were noted between OxLDL-E06 and Lp(a) (r=0.68, P<0.0001). MDA-LDL and Cu-OxLDL autoantibodies decreased, whereas apoB-IC levels increased after PCI, but both returned to baseline by 6 hours. Subsequently, IgM autoantibodies increased and peaked at 1 month and then returned to baseline, whereas IgG autoantibodies increased steadily over 6 months.

CONCLUSIONS

PCI results in acute plasma increases of Lp(a) and OxPL and results in short-term and long-term immunologic responses to OxLDL. OxPL that are released or generated during PCI are transferred to Lp(a), suggesting that Lp(a) may contribute acutely to a protective innate immune response. In settings of enhanced oxidative stress and chronically elevated Lp(a) levels, the atherogenicity of Lp(a) may stem from its capacity as a carrier of proinflammatory oxidation byproducts.

Is satisfaction with pain management a valid and reliable quality indicator for use in nursing homes?

OBJECTIVES

To determine whether satisfaction with pain management can be measured reliably in nursing homes and to gather preliminary data about the validity of satisfaction assessments in this population.

DESIGN

Cross-sectional interview study.

SETTING

Two urban nursing homes.

PARTICIPANTS

Sixty-six nursing home residents with pain.

MEASUREMENTS

Overall satisfaction with pain management, satisfaction with pain medication, experiences related to pain management, cognitive function, depressive symptoms, and retest reliability of overall satisfaction rating.

RESULTS

Most residents (60/66; 91%) could rate their overall satisfaction with pain management. Overall satisfaction was weakly correlated with pain severity at the time of the interview (Spearman correlation coefficient = -0.28; P =.033) and over the past week (-0.27; P =.038). Overall satisfaction was also negatively associated with the Geriatric Depression Scale score (-0.50; P <.001). Satisfaction with pain medication was associated with several ratings of the medication's beneficial effects, including improved activity, sleep, and speed of relief, but not with the frequency with which it caused side effects. Ratings of overall satisfaction showed good reliability overall (kappa = 0.62; P <.001) and for those with Mini-Mental State Examination scores greater than 21 (kappa = 0.70; P <.001) and 21 or less (kappa = 0.54; P =.004).

CONCLUSION

These results suggest that satisfaction with pain management can be measured reliably when residents are able to report their pain, but further research is needed before satisfaction with pain management can be incorporated into routine assessments in nursing homes.

The impact of angiotensin II receptor blockade and the DASH diet on markers of endogenous fibrinolysis

Hypertension is associated with impaired fibrinolysis. Both angiotensin receptor blockers (ARB) and the DASH (Dietary Approaches to Stop Hypertension) diet effectively lower blood pressure in hypertensive patients. Some evidence suggests that treatment with ARBs could increase fibrinolysis, however, data is conflicting. The impact of the DASH diet on fibrinolytic parameters is not known. Fifty-five hypertensive participants (35 African-American, 20 white) were randomly assigned to receive 8 weeks of either a control diet or the DASH diet. The diets did not differ in sodium content (approximately 3 g/day). Within each diet, individuals were randomly assigned to receive losartan or placebo for 4 weeks in double-blind, cross-over fashion. Tissue plasminogen activator (t-PA) antigen, t-PA activity, plasminogen activator inhibitor-1 (PAI-1) activity and plasma renin activity (PRA) were measured at the end of a 2-week run-in period on the control diet and after each treatment period. The DASH diet did not affect markers of fibrinolysis. Losartan significantly lowered t-PA antigen levels (-1.8 ng/mL, P = 0.045), but had no effect on t-PA or PAI-1 activities. This effect was more pronounced in whites (-4.1 ng/mL (P = 0.003)) compared with African-Americans (-0.3 ng/mL (P = 0.7), P-interaction = 0.03). Results were not materially affected by adjustment for basline values or changes in blood pressure. This study demonstrates that losartan reduces t-PA antigen levels in white, but not African-American hypertensive individuals. In contrast, the DASH diet had no significant effect on markers of fibrinolysis in whites or African-Americans.

Intercenter variance in clinical trials of head trauma--experience of the National Acute Brain Injury Study: Hypothermia

OBJECT

In a recently conducted trial of hypothermia in patients with severe brain injury, differences were found in the effects of hypothermia treatment among various centers. This analysis explores the reasons for such differences.

METHODS

The authors reviewed data obtained in 392 patients treated for severe brain injury. Prerandomization variables, critical physiological variables, treatment variables, and accrual methodologies were investigated among various centers. Hypothermia was found to be detrimental in patients older than the age of 45 years, beneficial in patients younger than 45 years of age in whom hypothermia was present on admission, and without effect in those in whom normothermia was documented on admission. Marginally significant differences (p < 0.054) in the intercenter outcomes of hypothermia-treated patients were likely the result of wide differences in the percentage of patients older than 45 years of age and in the percentage of patients in whom hypothermia was present on admission among centers. The trial sensitivity was likely diminished by significant differences in the incidence of mean arterial blood pressure (MABP) less than 70 mm Hg (p < 0.001) and cerebral perfusion pressure (CPP) less than 50 mm Hg (p < 0.05) but not intracranial pressure (ICP) greater than 25 mm Hg (not significant) among patients in the various centers. Hours of vasopressor usage (p < 0.03) and morphine dose (p < 0.001) and the percentage of dehydrated patients varied significantly among centers (p < 0.001). The participation of small centers increased intercenter variance and diminished the quality of data.

CONCLUSIONS

For Phase III clinical trials we recommend: 1) a detailed protocol specifying fluid and MABP, ICP, and CPP management: 2) continuous monitoring of protocol compliance; 3) a run-in period for new centers to test accrual and protocol adherence; and 4) inclusion of only centers in which patients are regularly randomized.

Vancomycin-resistant enterococci colonization in patients at seven hemodialysis centers

BACKGROUND

Vancomycin-resistant enterococci (VRE) are increasing in prevalence at many institutions, and are often reported in dialysis patients. We studied the prevalence of and risk factors for VRE at seven outpatient hemodialysis centers (three in Baltimore, MD, USA, and four in Richmond, VA, USA).

METHODS

Rectal or stool cultures were performed on consenting hemodialysis patients during December 1997 to April 1998. Consenting patients were recultured during May to July 1998 (median 120 days later). Clinical and laboratory data and functional status (1 to 10 scale: 1, normal function; 9, home attendant, not totally disabled; 10, disabled, living at home) were recorded.

RESULTS

Of 478 cultures performed, 20 (4.2%) were positive for VRE. Among the seven centers, the prevalence of VRE-positive cultures varied from 1.0 to 7.9%. Independently significant risk factors for a VRE-positive culture were a functional score of 9 to 10 (odds ratio 6.9, P < 0.001), antimicrobial receipt within 90 days before culture (odds ratio 6.1, P < 0.001), and a history of injection drug use (odds ratio 5.4, P = 0.004).

CONCLUSIONS

VRE-colonized patients were present at all seven participating centers, suggesting that careful infection-control precautions should be used at all centers to limit transmission. In agreement with previous studies, VRE colonization was more frequent in patients who had received antimicrobial agents recently, underscoring the importance of judicious antimicrobial use in limiting selection for this potential pathogen.

Relationship between systemic markers of inflammation and serum beta-carotene levels

BACKGROUND

Low serum levels of beta-carotene have been associated with increased risk of cancer and cardiovascular disease. However, in clinical trials, supplementation of the diet with beta-carotene either had no benefit or caused harm. This pattern of findings raises the possibility that confounding by other factors might explain the association between serum beta-carotene level and disease risk.

METHODS

We used data from 14 470 current smokers, ex-smokers, and never smokers aged 18 years or older who participated in the Third National Health and Nutrition Examination Survey to assess the relationship between serum beta-carotene and markers of inflammation (C-reactive protein and white blood cell count).

RESULTS

After adjustment for beta-carotene intake and other factors, geometric mean levels of serum beta-carotene for individuals with undetectable (< 0.22 mg/dL), mildly elevated (0.22-0.99 mg/dL), and clinically elevated (> or =1.0 mg/dL) C-reactive protein levels were 18.0, 16.1, and 13.6 microg/dL, respectively, in never smokers; 18.1, 15.7, and 13.9 microg/dL in ex-smokers; and 11.3, 10.2, and 9.4 microg/dL in current smokers (P< .001 for all). In corresponding analyses, white blood cell count was also inversely related to serum beta-carotene concentration (P< .05 for all).

CONCLUSIONS

The strong and inverse association of serum beta-carotene level with C-reactive protein level and white blood cell count suggests that the relationship between serum beta-carotene concentration and disease risk might be confounded by inflammation. More broadly, for beta-carotene and likely other nutrients, it seems unwise to interpret biomarker data as prima facie evidence of dietary intake without a more complete understanding of the physiologic processes that affect nutrient levels.

Quality of life in HCV-infection: lack of association with ALT levels

OBJECTIVES

To examine the impact of HCV infection in an Australian clinic population and identify the relationships between morbidity, psychosocial variables and one clinical indicator of HCV activity, alanine aminotransferase (ALT).

METHOD

Ninety-five untreated HCV-infected patients (21-69 years) in infectious and liver diseases clinics who were all positive for HCV-RNA and had no significant comorbidities or coinfections completed a survey containing the Short Form 36 (SF36), as well as the six-item Social Support Questionnaire (SSQ6), demographic items and questions concerning respondents' perceptions of their mode and duration of infection. Nine volunteers from this group participated in semi-structured qualitative interviews aimed at exploring the social impact of HCV status. These data were compared with serum ALT levels. SF36 scores were compared to population norms and according to participant variables.

RESULTS

Mean SF36 scores were significantly lower, across all modalities, than population norms. SF36 scores differed significantly according to age, sex, mode of infection, alcohol and methadone use, and satisfaction with social support. They did not differ significantly according to perceived or actual ALT level or pattern of ALT activity. Worry about ALT was prevalent (>50%) and this was independent of perceived ALT level.

CONCLUSIONS AND IMPLICATIONS

HCV-infection is associated with significantly reduced quality of life and includes the perception of substantial social discrimination. ALT levels are of limited usefulness in ascertainment of a person's sense of wellbeing and quality of life in HCV-infection. Increased support and information for affected individuals and measures aimed at countering social discrimination are important recommendations of the current study.

Effects on blood lipids of a blood pressure-lowering diet: the Dietary Approaches to Stop Hypertension (DASH) Trial

BACKGROUND

Effects of diet on blood lipids are best known in white men, and effects of type of carbohydrate on triacylglycerol concentrations are not well defined.

OBJECTIVE

Our goal was to determine the effects of diet on plasma lipids, focusing on subgroups by sex, race, and baseline lipid concentrations.

DESIGN

This was a randomized controlled outpatient feeding trial conducted in 4 field centers. The subjects were 436 participants of the Dietary Approaches to Stop Hypertension (DASH) Trial [mean age: 44.6 y; 60% African American; baseline total cholesterol: < or = 6.7 mmol/L (< or = 260 mg/dL)]. The intervention consisted of 8 wk of a control diet, a diet increased in fruit and vegetables, or a diet increased in fruit, vegetables, and low-fat dairy products and reduced in saturated fat, total fat, and cholesterol (DASH diet), during which time subjects remained weight stable. The main outcome measures were fasting total cholesterol, LDL cholesterol, HDL cholesterol, and triacylglycerol.

RESULTS

Relative to the control diet, the DASH diet resulted in lower total (-0.35 mmol/L, or -13.7 mg/dL), LDL- (-0.28 mmol/L, or -10.7 mg/dL), and HDL- (-0.09 mmol/L, or -3.7 mg/dL) cholesterol concentrations (all P < 0.0001), without significant effects on triacylglycerol. The net reductions in total and LDL cholesterol in men were greater than those in women by 0.27 mmol/L, or 10.3 mg/dL (P = 0.052), and by 0.29 mmol/L, or 11.2 mg/dL (P < 0.02), respectively. Changes in lipids did not differ significantly by race or baseline lipid concentrations, except for HDL, which decreased more in participants with higher baseline HDL-cholesterol concentrations than in those with lower baseline HDL-cholesterol concentrations. The fruit and vegetable diet produced few significant lipid changes.

CONCLUSIONS

The DASH diet is likely to reduce coronary heart disease risk. The possible opposing effect on coronary heart disease risk of HDL reduction needs further study.

Effect of ramipril vs amlodipine on renal outcomes in hypertensive nephrosclerosis: a randomized controlled trial

CONTEXT

Incidence of end-stage renal disease due to hypertension has increased in recent decades, but the optimal strategy for treatment of hypertension to prevent renal failure is unknown, especially among African Americans.

OBJECTIVE

To compare the effects of an angiotensin-converting enzyme (ACE) inhibitor (ramipril), a dihydropyridine calcium channel blocker (amlodipine), and a beta-blocker (metoprolol) on hypertensive renal disease progression.

DESIGN, SETTING, AND PARTICIPANTS

Interim analysis of a randomized, double-blind, 3 x 2 factorial trial conducted in 1094 African Americans aged 18 to 70 years with hypertensive renal disease (glomerular filtration rate [GFR] of 20-65 mL/min per 1.73 m(2)) enrolled between February 1995 and September 1998. This report compares the ramipril and amlodipine groups following discontinuation of the amlodipine intervention in September 2000.

INTERVENTIONS

Participants were randomly assigned to receive amlodipine, 5 to 10 mg/d (n = 217), ramipril, 2.5 to 10 mg/d (n = 436), or metoprolol, 50 to 200 mg/d (n = 441), with other agents added to achieve 1 of 2 blood pressure goals.

MAIN OUTCOME MEASURES

The primary outcome measure was the rate of change in GFR; the main secondary outcome was a composite index of the clinical end points of reduction in GFR of more than 50% or 25 mL/min per 1.73 m(2), end-stage renal disease, or death.

RESULTS

Among participants with a urinary protein to creatinine ratio of >0.22 (corresponding approximately to proteinuria of more than 300 mg/d), the ramipril group had a 36% (2.02 [SE, 0.74] mL/min per 1.73 m(2)/y) slower mean decline in GFR over 3 years (P =.006) and a 48% reduced risk of the clinical end points vs the amlodipine group (95% confidence interval [CI], 20%-66%). In the entire cohort, there was no significant difference in mean GFR decline from baseline to 3 years between treatment groups (P =.38). However, compared with the amlodipine group, after adjustment for baseline covariates the ramipril group had a 38% reduced risk of clinical end points (95% CI, 13%-56%), a 36% slower mean decline in GFR after 3 months (P =.002), and less proteinuria (P<.001).

CONCLUSION

Ramipril, compared with amlodipine, retards renal disease progression in patients with hypertensive renal disease and proteinuria and may offer benefit to patients without proteinuria.

A prospective study of vascular access infections at seven outpatient hemodialysis centers

Vascular access infections are a major cause of morbidity and mortality in hemodialysis patients, and the use of antimicrobials to treat such infections contributes to the emergence and spread of antimicrobial-resistant bacteria. To determine the incidence of and risk factors for vascular access infections, we studied hemodialysis patients at 7 outpatient dialysis centers (4 in Richmond, VA, and 3 in Baltimore, MD) during December 1997 to July 1998. Vascular access infections were defined as local signs (pus or redness) at the vascular access site or a positive blood culture with no known source other than the vascular access; and hospitalization or receipt of an intravenous (IV) antimicrobial. A total of 796 patients were followed for 4,134 patient-months. The vascular access infection rate was 3.5/100 patient-months, ie, patients had a 3.5% risk of infection each month. Independent risk factors were the specific dialysis unit where the patient was treated (relative hazard varying from 1.0 to 4.1 among the 7 centers), catheter access (relative hazard, 2.1 v implanted access), albumin level (relative hazard, 2.4 for lowest v highest quartile), urea reduction ratio (relative hazard, 2.2 for lowest v highest quartile), and hospitalizations during the previous 90 days (relative hazard, 4.9 for >/=6 v zero hospitalizations). These data confirm that vascular access infections are common in hemodialysis patients and that infection rates differ substantially among different centers. Catheter use should be minimized to reduce these infections. Additionally, the possibility that improved serum albumin and urea reduction ratio could reduce vascular access infections should be evaluated.

Origin of anthropoidea: dental evidence and recognition of early anthropoids in the fossil record, with comments on the Asian anthropoid radiation

Among the earliest fossil anthropoid primates known are Catopithecus browni, Serapia eocaena, Arsinoea kallimos, and Proteopithecus sylviae, from the late Eocene quarry L-41, Fayum Depression, Egypt. Two of these taxa, C. browni and S. eocaena, may be the oldest known members of the Propliopithecidae and Parapithecidae, respectively, while A. kallimos and P. sylviae are archaic anthropoids of less certain familial affiliation. Dental features of C. browni, S. eocaena, A. kallimos, and P. sylviae are compared with those of younger propliopithecids and parapithecids from the Fayum in order to determine the morphocline polarities of dental features among these early anthropoids. From this, a basal African anthropoid dental morphotype is constructed. Among the features of this morphotype are: dental formula of 2.1.3.3; incisors subvertically implanted and somewhat spatulate; p2 as large as p3, both lacking paraconids; p4 weakly obliquely oriented but not exodaenodont; all lower molars with small paraconids present; upper anterior premolars lacking protocone; upper molars with small, cingular hypocones, all cheek teeth nonbunodont; and canines projecting but not necessarily sexually dimorphic. Comparisons are made between this African anthropoid morphotype and two of the best-represented proposed basal anthropoids, Eosimias and Djebelemur, with the result that neither appears to be a good candidate to have been ancestral to the African anthropoids. Other possible basal simians such as Algeripithecus, Tabelia, and Biretia also are evaluated but are too poorly known for adequate analysis. The larger-bodied Asian primates Pondaungia, Amphipithecus, and Siamopithecus also are not likely ancestors for African anthropoids, but like Eosimias they may share a common ancestry. Despite many recent claims of an Asian origin for anthropoids, the evidence remains far from compelling. The true origins of Anthropoidea remain obscure.

Lack of effect of induction of hypothermia after acute brain injury

BACKGROUND

Induction of hypothermia in patients with brain injury was shown to improve outcomes in small clinical studies, but the results were not definitive. To study this issue, we conducted a multicenter trial comparing the effects of hypothermia with those of normothermia in patients with acute brain injury.

METHODS

The study subjects were 392 patients 16 to 65 years of age with coma after sustaining closed head injuries who were randomly assigned to be treated with hypothermia (body temperature, 33 degrees C), which was initiated within 6 hours after injury and maintained for 48 hours by means of surface cooling, or normothermia. All patients otherwise received standard treatment. The primary outcome measure was functional status six months after the injury.

RESULTS

The mean age of the patients and the type and severity of injury in the two treatment groups were similar. The mean (+/-SD) time from injury to randomization was 4.3+/-1.1 hours in the hypothermia group and 4.1+/-1.2 hours in the normothermia group, and the mean time from injury to the achievement of the target temperature of 33 degrees C in the hypothermia group was 8.4+/-3.0 hours. The outcome was poor (defined as severe disability, a vegetative state, or death) in 57 percent of the patients in both groups. Mortality was 28 percent in the hypothermia group and 27 percent in the normothermia group (P=0.79). The patients in the hypothermia group had more hospital days with complications than the patients in the normothermia group. Fewer patients in the hypothermia group had high intracranial pressure than in the normothermia group.

CONCLUSIONS

Treatment with hypothermia, with the body temperature reaching 33 degrees C within eight hours after injury, is not effective in improving outcomes in patients with severe brain injury.