Joanna M. Young

Betaine and Trimethylamine-N-Oxide as Predictors of Cardiovascular Outcomes Show Different Patterns in Diabetes Mellitus: An Observational Study

Background Betaine is a major osmolyte, also important in methyl group metabolism. Concentrations of betaine, its metabolite dimethylglycine and analog trimethylamine-N-oxide (TMAO) in blood are cardiovascular risk markers. Diabetes disturbs betaine: does diabetes alter associations between betaine-related measures and cardiovascular risk? Methods Plasma samples were collected from 475 subjects four months after discharge following an acute coronary admission. Death (n = 81), secondary acute MI (n = 87), admission for heart failure (n = 85), unstable angina (n = 72) and all cardiovascular events (n = 283) were recorded (median follow-up: 1804 days). Results High and low metabolite concentrations were defined as top or bottom quintile of the total cohort. In subjects with diabetes (n = 79), high plasma betaine was associated with increased frequencies of events; significantly for heart failure, hazard ratio 3.1 (1.2–8.2) and all cardiovascular events, HR 2.8 (1.4–5.5). In subjects without diabetes (n = 396), low plasma betaine was associated with events; significantly for secondary myocardial infarction, HR 2.1 (1.2–3.6), unstable angina, HR 2.3 (1.3–4.0), and all cardiovascular events, HR 1.4 (1.0–1.9). In diabetes, high TMAO was a marker of all outcomes, HR 2.7 (1.1–7.1) for death, 4.0 (1.6–9.8) for myocardial infarction, 4.6 (2.0–10.7) for heart failure, 9.1 (2.8–29.7) for unstable angina and 2.0 (1.1–3.6) for all cardiovascular events. In subjects without diabetes TMAO was only significant for death, HR 2.7 (1.6–4.8) and heart failure, HR 1.9 (1.1–3.4). Adding the estimated glomerular filtration rate to Cox regression models tended to increase the apparent risks associated with low betaine. Conclusions Elevated plasma betaine concentration is a marker of cardiovascular risk in diabetes; conversely low plasma betaine concentrations indicate increased risk in the absence of diabetes. We speculate that the difference reflects control of osmolyte retention in tissues. Elevated plasma TMAO is a strong risk marker in diabetes.

Improved cognitive performance after dietary supplementation with a Pinus radiata bark extract formulation.

Dietary interventions may have the potential to counter age‐related cognitive decline. Studies have demonstrated an improvement in age‐related cognitive impairment in animals after supplementation with plant extracts containing flavonoids but there are few human studies. This double‐blind, controlled study examined the effects on cognitive performance of a 5 week supplementation with Enzogenol® Pinus radiata bark extract containing flavonoids, in 42 males aged 50–65 years, with a body mass index >25. Participants were supplemented for 5 weeks either with Enzogenol® plus vitamin C, or with vitamin C only. A battery of computerized cognitive tests was administered, and cardiovascular and haematological parameters were assessed prior to and following supplementation. The speed of response for the spatial working memory and immediate recognition tasks improved after supplementation with Enzogenol® plus vitamin C, whereas vitamin C alone showed no improvements. A trend in a reduction of systolic blood pressure was observed with Enzogenol® plus vitamin C, but not with vitamin C alone. The blood safety parameters were unchanged. The findings suggest a beneficial effect of supplementation with Enzogenol® on cognition in older individuals. Larger studies are needed to ascertain its potential as a preventive treatment for age‐related cognitive decline. Copyright

Short-term statin treatment improves endothelial function and neurohormonal imbalance in normocholesterolaemic patients with non-ischaemic heart failure

Objectives: To investigate the effect of short-term statin treatment on impaired endothelium-dependent vasodilatation and haemodynamic abnormalities typically occurring in chronic heart failure (CHF). Methods: In a double-blind, crossover study endothelium-dependent vasodilatation was measured in conduit and resistance vessels of 23 patients with non-ischaemic CHF after 6 weeks of placebo and 40 mg atorvastatin. The haemodynamic impact was assessed by cardioendocrine hormones, echocardiography and clinical indicators of CHF. Results: Cholesterol concentrations were population average (low density lipoprotein 3.56 (SEM 0.16) mmol/l, triglycerides 1.70 (0.20) mmol/l and high density lipoprotein 1.17 (0.07) mmol/l). In resistance vessels, the area under the curve ratio during acetylcholine infusion increased from 9.2 (1.9) with placebo to 12.2 (2.1) with statin (p < 0.01). This improvement was reversed during co-infusion with the nitric oxide antagonist NG-monomethyl-l-arginine. In conduit arteries, flow-mediated dilatation increased from 5.64 (SEM 0.88)% with placebo to 6.83 (0.97)% with statin (p < 0.05). Endothelium-independent vasodilatation did not change (p  =  0.68 for conduit and p  =  0.45 for resistance vessels). Endothelin 1 and atrial natriuretic peptide (ANP) decreased from 1.57 (0.08) and 51.3 (1.0) with placebo to 1.42 (0.09) pg/ml (p < 0.05) and 42.1 (7.5) pmol/l (p < 0.05), respectively, with statin. Conclusions: In patients with non-ischaemic CHF and population-average cholesterol concentrations, short-term statin treatment improves endothelial function in conduit and resistance vessels and lowers plasma endothelin 1 and ANP concentrations.

Effectiveness of EDACS Versus ADAPT Accelerated Diagnostic Pathways for Chest Pain: A Pragmatic Randomized Controlled Trial Embedded Within Practice.

STUDY OBJECTIVE A 2-hour accelerated diagnostic pathway based on the Thrombolysis in Myocardial Infarction score, ECG, and troponin measures (ADAPT-ADP) increased early discharge of patients with suspected acute myocardial infarction presenting to the emergency department compared with standard care (from 11% to 19.3%). Observational studies suggest that an accelerated diagnostic pathway using the Emergency Department Assessment of Chest Pain Score (EDACS-ADP) may further increase this proportion. This trial tests for the existence and size of any beneficial effect of using the EDACS-ADP in routine clinical care. METHODS This was a pragmatic randomized controlled trial of adults with suspected acute myocardial infarction, comparing the ADAPT-ADP and the EDACS-ADP. The primary outcome was the proportion of patients discharged to outpatient care within 6 hours of attendance, without subsequent major adverse cardiac event within 30 days. RESULTS Five hundred fifty-eight patients were recruited, 279 in each arm. Sixty-six patients (11.8%) had a major adverse cardiac event within 30 days (ADAPT-ADP 29; EDACS-ADP 37); 11.1% more patients (95% confidence interval 2.8% to 19.4%) were identified as low risk in EDACS-ADP (41.6%) than in ADAPT-ADP (30.5%). No low-risk patients had a major adverse cardiac event within 30 days (0.0% [0.0% to 1.9%]). There was no difference in the primary outcome of proportion discharged within 6 hours (EDACS-ADP 32.3%; ADAPT-ADP 34.4%; difference -2.1% [-10.3% to 6.0%], P=.65). CONCLUSION There was no difference in the proportion of patients discharged early despite more patients being classified as low risk by the EDACS-ADP than the ADAPT-ADP. Both accelerated diagnostic pathways are effective strategies for chest pain assessment and resulted in an increased rate of early discharges compared with previously reported rates.

Effect of atorvastatin on plasma levels of asymmetric dimethylarginine in patients with non-ischaemic heart failure

Elevated plasma levels of asymmetric dimethylarginine (ADMA), an endothelial nitric oxide synthase (eNOS) inhibitor, may contribute to endothelial dysfunction in chronic heart failure (CHF). Since statins upregulate eNOS and ameliorate endothelial dysfunction in non‐ischaemic CHF, we hypothesized that this may be in part through modification of ADMA.

A Randomized, Double-Blind, Placebo-Controlled Crossover Study of Coenzyme Q10 Therapy in Hypertensive Patients With the Metabolic Syndrome

BACKGROUND Our aim was to examine the effects of adjunctive coenzyme Q(10) therapy on 24-h ambulatory blood pressure (BP) in subjects with the metabolic syndrome and inadequate BP control. METHODS In a randomized, double-blind, placebo-controlled 12-week crossover trial, coenzyme Q(10) (100 mg twice daily) or placebo was administrated to 30 subjects with the metabolic syndrome, and inadequate BP control (an average clinic BP of ≥140 systolic mm Hg or ≥130 mm Hg for patients with type 2 diabetes) while taking an unchanged, conventional antihypertensive regimen. Clinic and 24-h ambulatory BP were assessed pre- and post-treatment phases. The primary outcomes were the changes in 24-h systolic and diastolic BP during adjunctive therapy with coenzyme Q(10) vs. placebo and prespecified secondary outcomes included changes in BP loads. RESULTS Compared with placebo, treatment with coenzyme Q(10) was not associated with statistically significant reductions in systolic (P = 0.60) or diastolic 24-h ambulatory BP (P = 0.12) or heart rate (P = 0.10), although daytime diastolic BP loads, were significantly lower during coenzyme Q(10) administration with thresholds set at >90 mm Hg (P = 0.007) and ≥85 mm Hg (P = 0.03). Coenzyme Q(10) was well tolerated and was not associated with any clinically relevant changes in safety parameters. CONCLUSIONS Although it is possible that coenzyme Q(10) may improve BP control under some circumstances, any effects are likely to be smaller than reported in previous meta-analyses. Furthermore, our data suggest that coenzyme Q(10) is not currently indicated as adjunctive antihypertensive treatment for patients with the metabolic syndrome whose BP control is inadequate, despite regular antihypertensive therapy.

Comparative effects of enzogenol® and vitamin C supplementation versus vitamin C alone on endothelial function and biochemical markers of oxidative stress and inflammation in chronic smokers

Chronic smoking is associated with endothelial dysfunction and inflammation, with oxidative stress contributing to both these processes. In this study, we investigated the effect of combined antioxidant treatment with Enzogenol®, a flavonoid extract from the bark of Pinus radiata and vitamin C, over and above vitamin C alone, on endothelial function, plasma markers of inflammation and oxidative stress, blood pressure (BP) and anthropometrics. Forty-four chronic smokers without established cardiovascular disease were assigned randomly to receive either 480 mg Enzogenol® and 60 mg vitamin C, or 60 mg vitamin C alone daily for 12 weeks. Endothelial function in the brachial artery was assessed by flow-mediated vasodilation (FMD). FMD improved in both treatment groups (p < 0.001), with no significant difference between the two groups (p = 0.84). In the group receiving Enzogenol® and vitamin C, protein carbonyl levels were significantly reduced compared to the group taking vitamin C alone (p = 0.03). Enzogenol® and vitamin C resulted in a significant reduction in fibrinogen levels in heavy smokers compared with vitamin C alone (p < 0.009). These findings demonstrated that co-supplementation with Enzogenol® and vitamin C in smokers conferred no additional beneficial effect on macrovascular endothelial function over and above that seen in the vitamin C alone group. However, Enzogenol® did demonstrate additional favourable effects on protein oxidative damage and fibrinogen levels.

Relationship between plasma coenzyme Q10, asymmetric dimethylarginine and arterial stiffness in patients with phenotypic or genotypic familial hypercholesterolemia on long-term statin therapy

OBJECTIVE We investigated whether statin-treated heterozygous familial hypercholesterolemic (FH) patients have lower plasma coenzyme Q(10) (CoQ(10)) levels than low-density lipoprotein receptor (LDLR) mutation negative FH patients on equivalent statin doses, and whether lower CoQ(10) concentrations are associated with increased arterial stiffness. METHODS Thirty LDLR mutation negative patients with clinical FH and 30 mutation positive FH patients matched for gender, statin duration and dose, and a further 30 controls were studied. Plasma CoQ(10) and asymmetric dimethylarginine (ADMA) levels were measured by HPLC and the augmentation index by pulse wave analysis. RESULTS Plasma CoQ(10) levels, and the ratios of CoQ(10) to total cholesterol and LDL-cholesterol were similar in treated FH patients with identified LDLR mutations to mutation negative patients on equivalent doses of statin therapy (p>0.05). CoQ(10) and lipid levels were also comparable to controls not using any lipid modifying treatment. Arterial stiffness was higher in mutation negative patients (p=0.04) and there was a trend for an increase in mutation positive patients (p=0.09). ADMA was higher in the mutation positive group (p<0.01). The augmentation index corrected for age, blood pressure, and heart rate, was negatively correlated with plasma CoQ(10) within FH patients (p<0.05). CONCLUSION Long-term, high-dose statin therapy does not lead to subnormal CoQ(10) concentrations in patients with phenotypic or genotypic FH. Arterial stiffness is elevated in FH patients compared to untreated controls, and low CoQ(10) levels are associated with increased arterial stiffness. CoQ(10) supplementation trials are warranted in FH patients.

The utility of presentation and 4-hour high sensitivity troponin I to rule-out acute myocardial infarction in the emergency department

OBJECTIVES International guidance recommends that early serial sampling of high sensitivity troponin be used to accurately identify acute myocardial infarction (AMI) in chest pain patients. The background evidence for this approach is limited. We evaluated whether on presentation and 4-hour high-sensitivity troponin I (hs-cTnI) could be used to accurately rule-out AMI. DESIGN AND METHODS hs-cTnI was measured on presentation and at 4-hours in adult patients attending an emergency department with possible acute coronary syndrome. We determined the sensitivity for AMI for at least one hs-cTnI above the 99th percentile for a healthy population or alone or in combination with new ischemic ECG changes. Both overall and sex-specific 99th percentiles were assessed. Patients with negative tests were designated low-risk. RESULTS 63 (17.1%) of 368 patients had AMI. The median (interquartile range) time from symptom onset to first blood sampling was 4.8h (2.8-8.6). The sensitivity of the presentation and 4h hs-cTnI using the overall 99th percentile was 92.1% (95% CI 82.4% to 97.4%) and negative predictive value 95.4% (92.3% to 97.4%) with 78.3% low-risk. Applying the sex-specific 99th percentile did not change the sensitivity. The addition of ECG did not change the sensitivity. CONCLUSION Hs-cTnI >99th percentile thresholds measured on presentation and at 4-hours was not a safe strategy to rule-out AMI in this clinical setting irrespective of whether sex-specific 99th percentiles were used, or whether hs-cTnI was combined with ECG results.

Pharmacokinetic Comparison of a Generic Coenzyme Q10 Solubilizate and a Formulation with Soybean Phytosterols

Coenzyme Q10 (CoQ10) is essential for all cells, and deficiency has been implicated in cardiovascular disease. Plant phytosterols inhibit cholesterol absorption, and may thereby also reduce cardiovascular risk. This study compared the relative bioavailability of CoQ10 solubilized in low‐dose soybean phytosterols (SterolQ10) with a generic CoQ10 solubilizate. In a randomized, cross‐over design, 36 healthy males received a single 100 mg dose of CoQ10, as SterolQ10 or generic CoQ10, with a two‐week washout between treatments. Plasma CoQ10 was analysed at baseline, and at 2, 4, 6, 8 and 10 h after supplement ingestion. Subjects were then administered either 100 mg/day of generic CoQ10 or SterolQ10 for 4 weeks. Fasting plasma CoQ10 levels were measured at baseline and following supplementation. The two preparations were bioequivalent in regard to the area under the curve (AUC0–10h) and maximum increase in concentration (Cmax), with geometric mean ratios of 0.89 (CI 0.81–0.98) and 0.88 (CI 0.80–0.96), respectively. Four‐weeks of CoQ10 resulted in a comparable twofold increase in CoQ10 levels for both formulations (p < 0.001), which was similar between preparations (p = 0.74). The combined CoQ10 and phytosterol formulation, SterolQ10, showed bioequivalence to the generic CoQ10 following a single CoQ10 dose, and demonstrated comparable bioavailability following multiple dose administration. Copyright