Richard J. Woodman

EFFECT OF EICOSAPENTAENOIC ACID AND DOCOSAHEXAENOIC ACID ON OXIDATIVE STRESS AND INFLAMMATORY MARKERS IN TREATED- HYPERTENSIVE TYPE 2 DIABETIC SUBJECTS

n-3 fatty acids reduce the risk of cardiovascular disease via a number of possible mechanisms. Despite this, there has been concern that these fatty acids may increase lipid peroxidation. The data in vivo are inconclusive, due in part to limitations in the methodologies. In this regard, the measurement of F2-isoprostanes provides a reliable assessment of in vivo lipid peroxidation and oxidant stress. This study aimed to assess the effects of supplementation with purified eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA), the two major n-3 fatty acids, on urinary F2-isoprostanes and markers of inflammation, in type 2 diabetic patients. In a double-blind, placebo controlled trial of parallel design, 59 nonsmoking, treated-hypertensive, type 2 diabetic subjects, were randomized to 4 g daily of purified EPA, DHA, or olive oil for 6 weeks, while maintaining their usual diet. F2-isoprostanes, measured using gas chromatography-mass spectrometry in 24 h urines and C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha), were measured before and after intervention. Thirty-nine men and 12 women aged 61.2 +/- 1.2 years, with body mass index (BMI), 29.5 +/- 0.5 kg/m2; 24 h blood pressure, 138/73 mmHg; HbA1c, 7.3 +/- 0.1% and fasting glucose, 7.9 +/- 0.2 mmol/l completed the intervention. Baseline urinary F2-isoprostanes were positively associated with HbA1c (p=.011) and fasting glucose (p=.032). Relative to the olive oil group, postintervention urinary F2-isoprostanes were decreased 19% by EPA (p=.017) and 20% by DHA (p=.014). There were no significant changes in CRP, IL-6, and TNF-alpha following EPA or DHA supplementation. In regression analysis, Delta F2-isoprostanes were positively associated with Delta HbA1c (p=.007) independent of treatment group; and with Delta TNF-alpha (p=.034) independent of age, gender, BMI, and treatment group. There were no associations with Delta CRP or Delta IL-6. This study is the first report demonstrating that either EPA or DHA reduce in vivo oxidant stress without changing markers of inflammation, in treated hypertensive, type 2 diabetic subjects.

THE INDEPENDENT EFFECTS OF EICOSAPENTAENOIC ACID AND DOCOSAHEXAENOIC ACID ON CARDIOVASCULAR RISK FACTORS IN HUMANS

Purpose of reviewThis review details the independent effects of purified eicosapentaenoic acid and docosahexaenoic acid on cardiovascular risk factors in humans. We report data from the recent literature and our own controlled clinical trials which compared the independent effects of these fatty acids in individuals at increased risk of cardiovascular disease, namely overweight hyperlipidaemic men and treated-hypertensive, type 2 diabetic men and women. We discuss the biological effects of these fatty acids and the potential mechanisms through which they may affect cardiovascular disease risk factors. Recent findingsA cardioprotective effect for ω3 fatty acids is supported by prospective studies demonstrating an inverse association between fish intake and coronary heart disease mortality. Data from secondary prevention trials support a reduction in ventricular fibrillation as a primary mechanism for the decreased incidence of myocardial infarction. Clinical trials and experimental studies have shown that ω3 fatty acids have many other potentially important antiatherogenic and antithrombotic effects. Omega-3 fatty acids lower blood pressure and heart rate, improve dyslipidaemia, reduce inflammation, and improve vascular and platelet function. These favourable effects have until recently been primarily attributed to the ω3 fatty acid eicosapentaenoic acid, which is present in large amounts in fish oil. Controlled studies in humans now demonstrate that docosahexaenoic acid, although often present in lower quantities, has equally important anti-arrhythmic, anti-thrombotic and anti-atherogenic effects. SummaryAvailable evidence strongly suggests that eicosapentaenoic acid and docosahexaenoic acid have differing haemodynamic and anti-atherogenic properties. The effects of the two fatty acids may also differ depending on the target population.

Effects of purified eicosapentaenoic acid and docosahexaenoic acid on platelet, fibrinolytic and vascular function in hypertensive type 2 diabetic patients

BACKGROUND Type 2 diabetes and hypertension are both associated with an increased risk of atherothrombosis. We assessed whether purified eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from fish oil have differential effects on platelet, fibrinolytic and vascular function in patients with both conditions. METHODS In a double-blind placebo-controlled trial of parallel design, 59 treated-hypertensive Type 2 diabetic men and postmenopausal women, were randomised to 4 g/day of EPA, DHA or olive oil (placebo) for 6 weeks. Collagen and PAF-stimulated platelet aggregation, collagen-stimulated thromboxane release (TXB2), plasma tPA and PAI-1 antigens, von Willebrand factor, p-selectin, and flow-mediated and glyceryl-trinitrate-mediated dilatation of the brachial artery, were examined before and at the end of intervention. RESULTS Thirty-nine men and 12 women aged 61.2+/-1.2 year completed the study. Relative to placebo, DHA but not EPA supplementation significantly reduced collagen aggregation (16.9%, P=0.05) and TXB2 (18.8%, P=0.03). There were no significant changes in either PAF-stimulated platelet aggregation, fibrinolytic function or vascular function in either the EPA or DHA group relative to placebo. CONCLUSION Highly purified DHA may be a more effective anti-thrombotic agent than EPA. However, longer-term studies assessing morbidity and mortality are needed in order to establish if DHA contributes to reducing CHD amongst Type 2 diabetic patients with treated hypertension.

Late-life anemia is associated with increased risk of recurrent falls

Objectives: To examine whether anemia is associated with a higher incidence of recurrent falls.

The omega-3 fatty acids EPA and DHA decrease plasma F2-isoprostanes: Results from two placebo-controlled interventions

Abstract Omega-3 (ω3) fatty acids, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), protect against cardiovascular disease. Despite these benefits, concern remains that ω3 fatty acids may increase lipid peroxidation. It has previously been shown that urinary F2-isoprostanes (F2-IsoPs) were reduced following ω3 fatty acid supplementation in humans. It is now determined whether EPA or DHA supplementation affects plasma F2-IsoPs. In two 6-week placebo-controlled interventions, Study A: overweight, dyslipidaemic men; and Study B: treated-hypertensive Type 2 diabetic, patients were randomized to 4 g daily EPA, DHA. Post-intervention plasma F2-IsoPs were significantly reduced by EPA (24% in Study A, 19% in Study B) and by DHA (14% in Study A, 23% in Study B) relative to the olive oil group. The fall in plasma F2-IsoPs was not altered in analyses that corrected for changes in plasma arachidonic acid, which was reduced with EPA and DHA supplementation. Neither F3- nor F4-IsoPs were observed in plasma in both studies. These results show that in humans, EPA and DHA reduce in vivo oxidant stress as measured in human plasma and urine.

Mechanisms, significance and treatment of vascular dysfunction in type 2 diabetes mellitus: focus on lipid-regulating therapy.

Endothelial dysfunction and increased arterial stiffness occur early in the pathogenesis of diabetic vasculopathy. They are both powerful independent predictors of cardiovascular risk. Advances in non-invasive methodologies have led to widespread clinical investigation of these abnormalities in diabetes mellitus, generating a wealth of new knowledge concerning the mechanisms of vascular dysfunction, risk factor associations and potential treatment targets.Endothelial dysfunction primarily reflects decreased availability of nitric oxide (NO), a critical endothelium-derived vasoactive factor with vasodilatory and anti-atherosclerotic properties. Techniques for assessing endothelial dysfunction include ultrasonographic measurement of flow-mediated vasodilatation of the brachial artery and plethysmography measurement of forearm blood flow responses to vasoactive agents. Arterial stiffness may be assessed using pulse wave analysis to generate measures of pulse wave velocity, arterial compliance and wave reflection.The pathogenesis of endothelial dysfunction in type 2 diabetes is multifactorial, with principal contributors being oxidative stress, dyslipidaemia and hyperglycaemia. Elevated blood glucose levels drive production of reactive oxidant species (ROS) via multiple pathways, resulting in uncoupling of mitochondrial oxidative phosphorylation and endothelial NO synthase (eNOS) activity, reducing NO availability and generating further ROS. Hyperglycaemia also contributes to accelerated arterial stiffening by increasing formation of advanced glycation end-products (AGEs), which alter vessel wall structure and function. Diabetic dyslipidaemia is characterised by accumulation of triglyceride-rich lipoproteins, small dense low-density lipoprotein (LDL) particles, reduced high-density lipoprotein (HDL)-cholesterol and increased postprandial free fatty acid flux. These lipid abnormalities contribute to increasing oxidative stress and may directly inhibit eNOS activity.Although lipid-regulating agents such as HMG-CoA reductase inhibitors (statins), fibric acid derivatives (fibrates) and fish oils are used to treat diabetic dyslipidaemia, their impact on vascular function is less clear. Studies in type 2 diabetes have yielded inconsistent results, but this may reflect sampling variation and the potential over-riding influence of oxidative stress, dysglycaemia and insulin resistance on endothelial dysfunction. Results of positive intervention trials suggest that improvement in vascular function is mediated by both lipid and non-lipid mechanisms, including anti-inflammatory, anti-oxidative and direct effects on the arterial wall. Other treatments, such as renin-angiotensin-aldosterone system antagonists, insulin sensitisers and lifestyle-based interventions, have shown beneficial effects on vascular function in type 2 diabetes. Novel approaches, targeting eNOS and AGEs, are under development, as are new lipid-regulating therapies that more effectively lower LDL-cholesterol and raise HDL-cholesterol. Combination therapy may potentially increase therapeutic efficacy and permit use of lower doses, thereby reducing the risk of adverse drug effects and interactions. Concomitant treatments that specifically target oxidative stress may also improve endothelial dysfunction in diabetes. Vascular function studies can be used to explore the therapeutic potential and mechanisms of action of new and established interventions, and provide useful surrogate measures for cardiovascular endpoints in clinical trials.

Drugs with anticholinergic effects and cognitive impairment, falls and all‐cause mortality in older adults: A systematic review and meta‐analysis

AIM The aim was to investigate associations between drugs with anticholinergic effects (DACEs) and cognitive impairment, falls and all-cause mortality in older adults. METHODS A literature search using CINAHL, Cochrane Library, Embase and PubMed databases was conducted for randomized controlled trials, prospective and retrospective cohort and case-control studies examining the use of DACEs in subjects ≥65 years with outcomes on falls, cognitive impairment and all-cause mortality. Retrieved articles were published on or before June 2013. Anticholinergic exposure was investigated using drug class, DACE scoring systems (anticholinergic cognitive burden scale, ACB; anticholinergic drug scale, ADS; anticholinergic risk scale, ARS; anticholinergic component of the drug burden index, DBIAC ) or assessment of individual DACEs. Meta-analyses were performed to pool the results from individual studies. RESULTS Eighteen studies fulfilled the inclusion criteria (total 124 286 participants). Exposure to DACEs as a class was associated with increased odds of cognitive impairment (OR 1.45, 95% CI 1.16, 1.73). Olanzapine and trazodone were associated with increased odds and risk of falls (OR 2.16, 95% CI 1.05, 4.44; RR 1.79, 95% CI 1.60, 1.97, respectively), but amitriptyline, paroxetine and risperidone were not (RR 1.73, 95% CI 0.81, 2.65; RR 1.80, 95% CI 0.81, 2.79; RR 1.39, 95% CI 0.59, 3.26, respectively). A unit increase in the ACB scale was associated with a doubling in odds of all-cause mortality (OR 2.06, 95% CI 1.82, 2.33) but there were no associations with the DBIAC (OR 0.88, 95% CI 0.55, 1.42) or the ARS (OR 3.56, 95% CI 0.29, 43.27). CONCLUSIONS Certain individual DACEs or increased overall DACE exposure may increase the risks of cognitive impairment, falls and all-cause mortality in older adults.

Efficacy of a Chronic Disease Management Model for Patients With Chronic Liver Failure

BACKGROUND & AIMS Despite the economic impacts of chronic liver failure (CLF) and the success of chronic disease management (CDM) programs in routine clinical practice, there have been no randomized controlled trials of CDM for CLF. We investigated the efficacy of CDM programs for CLF patients in a prospective, controlled trial. METHODS Sixty consecutive patients with cirrhosis and complications from CLF were assigned randomly to groups given intervention (n = 40) or usual care (n = 20), from 2009 to 2010. The 12-month intervention comprised 4 CDM components: delivery system redesign, self-management support, decision support, and clinical information systems. The primary outcome was the number of days spent in a hospital bed for liver-related reasons. Secondary outcomes were rates of other hospital use measures, rate of attendance at planned outpatient care, disease severity, quality of life, and quality of care. RESULTS The intervention did not reduce the number of days patients spent in hospital beds for liver-related reasons, compared with usual care (17.8 vs 11.0 bed days/person/y, respectively; incidence rate ratio, 1.6; 95% confidence interval, 0.5-4.8; P = .39), or affect other measures of hospitalization. Patients given the intervention had a 30% higher rate of attendance at outpatient care (incidence rate ratio, 1.3; 95% confidence interval, 1.1-1.5; P = .004) and significant increases in quality of care, based on adherence to hepatoma screening, osteoporosis and vaccination guidelines, and referral to transplant centers (P < .05 for all). CONCLUSIONS In a pilot study to determine the efficacy of CDM for patients with CLF, patients receiving CDM had significant increases in attendance at outpatient centers and quality of care, compared with patients who did not receive CDM. However, CDM did not appear to reduce hospital admission rates or disease severity or improve patient quality of life. Larger trials with longer follow-up periods are required to confirm these findings and assess cost effectiveness.

The Impact of Traditional Cardiovascular Risk Factors on Cardiovascular Outcomes in Patients with Rheumatoid Arthritis: A Systematic Review and Meta-Analysis

Background Rheumatoid arthritis (RA) is known to increase the risk of cardiovascular (CV) disease. However, the individual impact of traditional CV risk factors in RA is unknown. Objective To assess the strength of the association between individual CV risk factors and rate of either myocardial infarction (MI), combined CV morbidity (MI, angina pectoris, heart failure, stroke, and peripheral arterial disease (PAD)) or CV mortality in RA patients. Methods RA studies reporting traditional CV risk factors [hypertension, type 2 diabetes (T2D), smoking, hypercholesterolaemia, obesity, and physical inactivity] as exposures and MI, CV morbidity (MI, angina, heart failure, stroke, and PAD combined) or CV mortality alone as outcomes were searched until March 2013 using MEDLINE, Scopus and Cochrane. Meta-analyses combined relative risk (RR) estimates from each study where either the RR and 95% confidence intervals or where raw counts were available. Results Ten studies reporting sufficient data for inclusion into meta-analyses were identified. Relevant data was available for each risk factor and MI and CV morbidity but no studies reported on CV mortality. Risk of MI increased in RA patients with hypertension (RR 1.84, 95% CI 1.38, 2.46) and T2D (RR 1.89, 95% CI 1.36, 2.63). CV morbidity increased with hypertension (RR 2.24, 95% CI 1.42, 3.06), T2D (RR 1.94, 95% CI 1.58, 2.30), smoking (RR 1.50, 95% CI 1.15, 1.84), hypercholesterolaemia (RR 1.73, 95% CI 1.03, 2.44) and obesity (RR 1.16, 95% CI 1.03, 1.29) but not with physical inactivity (RR 1.00, 95% CI 0.71, 1.29). Conclusion Hypertension, T2D, smoking, hypercholesterolaemia and obesity increased CV risk in patients with RA. These results highlight the importance of managing CV risk factors in RA, similarly to non-RA patients.

Randomized clinical trial of immunogenicity and safety of a recombinant H1N1/2009 pandemic influenza vaccine containing Advax™ polysaccharide adjuvant.

BACKGROUND Timely vaccine supply is critical during influenza pandemics. A recombinant hemagglutinin (rHA)-based vaccine could overcome production hurdles of egg-based vaccines but has never previously been tested in a real-life pandemic setting. The primary aim was to determine the efficacy of a recombinant pandemic vaccine and whether its immunogenicity could be enhanced by a novel polysaccharide adjuvant (Advax™). METHODS 281 adults aged 18-70 years were recruited in a randomized, subject and observer blinded, parallel-group study of rHA H1N1/2009 vaccine with or without adjuvant. Immunizations were at 0 and 3 weeks with rHA 3, 11 or 45 μg. Serology and safety was followed for 6 months. RESULTS At baseline, only 9.1% of subjects (95% CI: 6.0-13.2) had seroprotective H1N1/2009 titers. Seroconversion rates varied by rHA dose, presence of adjuvant, subject age and number of immunizations. Eighty percent (95% CI: 52-96) of 18-49 year olds who received rHA 45 μg with adjuvant were seroprotected at week 3, representing a 11.1-fold increase in antibody titers from baseline. Advax™ adjuvant increased seroprotection rates by 1.9 times after the first, and 2.5 times after the second, immunization when compared to rHA alone. Seroprotection was sustained at 26 weeks and the vaccine was well tolerated with no safety issues. CONCLUSIONS The study confirmed the ability to design, manufacture, and release a recombinant vaccine within a short time from the start of an actual influenza pandemic. Advax™ adjuvant significantly enhanced rHA immunogenicity.