14 research outputs found
Perspectives in Global Helioseismology, and the Road Ahead
We review the impact of global helioseismology on key questions concerning
the internal structure and dynamics of the Sun, and consider the exciting
challenges the field faces as it enters a fourth decade of science
exploitation. We do so with an eye on the past, looking at the perspectives
global helioseismology offered in its earlier phases, in particular the
mid-to-late 1970s and the 1980s. We look at how modern, higher-quality, longer
datasets coupled with new developments in analysis, have altered, refined, and
changed some of those perspectives, and opened others that were not previously
available for study. We finish by discussing outstanding challenges and
questions for the field.Comment: Invited review; to appear in Solar Physics (24 pages, 6 figures
The Gaia-ESO Survey: The most metal-poor stars in the Galactic bulge
We present the first results of the EMBLA survey (Extremely Metal-poor BuLge stars with AAOmega), aimed at finding metal-poor stars in the Milky Way bulge, where the oldest stars should now preferentially reside. EMBLA utilizes SkyMapper photometry to pre-select metal-poor candidates, which are subsequently confirmed using AAOmega spectroscopy. We describe the discovery and analysis of four bulge giants with -2.72 = [Fe/H] = -2.48, the lowest metallicity bulge stars studied with high-resolution spectroscopy to date. Using FLAMES/UVES spectra through the Gaia-ESO Survey we have derived abundances of twelve elements. Given the uncertainties, we find a chemical similarity between these bulge stars and halo stars of the same metallicity, although the abundance scatter may be larger, with some of the stars showing unusual [a/Fe] ratios
Alirocumab Reduces Total Nonfatal Cardiovascular and Fatal Events The ODYSSEY OUTCOMES Trial
The authors thank the
patients, study coordinators, and investigators who
participated in this trial; and Sophie Rushton-Smith,
PhD (MedLink Healthcare Communications, London),
for providing editorial assistance in the preparation
of the manuscript (limited to editing for style,
referencing, and figure and table editing).BACKGROUND The ODYSSEY OUTCOMES (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome
During Treatment With Alirocumab) trial compared alirocumab with placebo, added to high-intensity or
maximum-tolerated statin treatment, after acute coronary syndrome (ACS) in 18,924 patients. Alirocumab reduced the
first occurrence of the primary composite endpoint and was associated with fewer all-cause deaths.
OBJECTIVES This pre-specified analysis determined the extent to which alirocumab reduced total (first and
subsequent) nonfatal cardiovascular events and all-cause deaths in ODYSSEY OUTCOMES.
METHODS Hazard functions for total nonfatal cardiovascular events (myocardial infarction, stroke, ischemia-driven
coronary revascularization, and hospitalization for unstable angina or heart failure) and death were jointly estimated,
linked by a shared frailty accounting for patient risk heterogeneity and correlated within-patient nonfatal events. An
association parameter also quantified the strength of the linkage between risk of nonfatal events and death. The model
provides accurate relative estimates of nonfatal event risk if nonfatal events are associated with increased risk for death.
RESULTS With 3,064 first and 5,425 total events, 190 fewer first and 385 fewer total nonfatal cardiovascular events or
deaths were observed with alirocumab compared with placebo. Alirocumab reduced total nonfatal cardiovascular events
(hazard ratio: 0.87; 95% confidence interval: 0.82 to 0.93) and death (hazard ratio: 0.83; 95% confidence interval:
0.71 to 0.97) in the presence of a strong association between nonfatal and fatal event risk.
CONCLUSIONS In patients with ACS, the total number of nonfatal cardiovascular events and deaths prevented
with alirocumab was twice the number of first events prevented. Consequently, total event reduction is a
more comprehensive metric to capture the totality of alirocumab clinical efficacy after ACS
Effect of Alirocumab on Mortality After Acute Coronary Syndromes An Analysis of the ODYSSEY OUTCOMES Randomized Clinical Trial
Background: Previous trials of PCSK9 (proprotein convertase subtilisin-kexin type 9) inhibitors demonstrated reductions in major adverse cardiovascular events, but not death. We assessed the effects of alirocumab on death after index acute coronary syndrome. Methods: ODYSSEY OUTCOMES (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) was a double-blind, randomized comparison of alirocumab or placebo in 18 924 patients who had an ACS 1 to 12 months previously and elevated atherogenic lipoproteins despite intensive statin therapy. Alirocumab dose was blindly titrated to target achieved low-density lipoprotein cholesterol (LDL-C) between 25 and 50 mg/dL. We examined the effects of treatment on all-cause death and its components, cardiovascular and noncardiovascular death, with log-rank testing. Joint semiparametric models tested associations between nonfatal cardiovascular events and cardiovascular or noncardiovascular death. Results: Median follow-up was 2.8 years. Death occurred in 334 (3.5%) and 392 (4.1%) patients, respectively, in the alirocumab and placebo groups (hazard ratio [HR], 0.85; 95% CI, 0.73 to 0.98; P=0.03, nominal P value). This resulted from nonsignificantly fewer cardiovascular (240 [2.5%] vs 271 [2.9%]; HR, 0.88; 95% CI, 0.74 to 1.05; P=0.15) and noncardiovascular (94 [1.0%] vs 121 [1.3%]; HR, 0.77; 95% CI, 0.59 to 1.01; P=0.06) deaths with alirocumab. In a prespecified analysis of 8242 patients eligible for >= 3 years follow-up, alirocumab reduced death (HR, 0.78; 95% CI, 0.65 to 0.94; P=0.01). Patients with nonfatal cardiovascular events were at increased risk for cardiovascular and noncardiovascular deaths (P= 100 mg/dL (2.59 mmol/L) had a greater absolute risk of death and a larger mortality benefit from alirocumab (HR, 0.71; 95% CI, 0.56 to 0.90; P-interaction=0.007). In the alirocumab group, all-cause death declined with achieved LDL-C at 4 months of treatment, to a level of approximately 30 mg/dL (adjusted P=0.017 for linear trend). Conclusions: Alirocumab added to intensive statin therapy has the potential to reduce death after acute coronary syndrome, particularly if treatment is maintained for >= 3 years, if baseline LDL-C is >= 100 mg/dL, or if achieved LDL-C is low.Cardiolog
Effects of alirocumab on cardiovascular and metabolic outcomes after acute coronary syndrome in patients with or without diabetes: a prespecified analysis of the ODYSSEY OUTCOMES randomised controlled trial
Background After acute coronary syndrome, diabetes conveys an excess risk of ischaemic cardiovascular events. A reduction in mean LDL cholesterol to 1.4-1.8 mmol/L with ezetimibe or statins reduces cardiovascular events in patients with an acute coronary syndrome and diabetes. However, the efficacy and safety of further reduction in LDL cholesterol with an inhibitor of proprotein convertase subtilisin/kexin type 9 (PCSK9) after acute coronary syndrome is unknown. We aimed to explore this issue in a prespecified analysis of the ODYSSEY OUTCOMES trial of the PCSK9 inhibitor alirocumab, assessing its effects on cardiovascular outcomes by baseline glycaemic status, while also assessing its effects on glycaemic measures including risk of new-onset diabetes.Methods ODYSSEY OUTCOMES was a randomised, double-blind, placebo-controlled trial, done at 1315 sites in 57 countries, that compared alirocumab with placebo in patients who had been admitted to hospital with an acute coronary syndrome (myocardial infarction or unstable angina) 1-12 months before randomisation and who had raised concentrations of atherogenic lipoproteins despite use of high-intensity statins. Patients were randomly assigned (1: 1) to receive alirocumab or placebo every 2 weeks; randomisation was stratified by country and was done centrally with an interactive voice-response or web-response system. Alirocumab was titrated to target LDL cholesterol concentrations of 0.65-1.30 mmol/L. In this prespecified analysis, we investigated the effect of alirocumab on cardiovascular events by glycaemic status at baseline (diabetes, prediabetes, or normoglycaemia)-defined on the basis of patient history, review of medical records, or baseline HbA(1c) or fasting serum glucose-and risk of new-onset diabetes among those without diabetes at baseline. The primary endpoint was a composite of death from coronary heart disease, non-fatal myocardial infarction, fatal or non-fatal ischaemic stroke, or unstable angina requiring hospital admission. ODYSSEY OUTCOMES is registered with ClinicalTrials. gov, number NCT01663402.Findings At study baseline, 5444 patients (28.8%) had diabetes, 8246 (43.6%) had prediabetes, and 5234 (27.7%) had normoglycaemia. There were no significant differences across glycaemic categories in median LDL cholesterol at baseline (2.20-2.28 mmol/L), after 4 months' treatment with alirocumab (0.80 mmol/L), or after 4 months' treatment with placebo (2.25-2.28 mmol/L). In the placebo group, the incidence of the primary endpoint over a median of 2.8 years was greater in patients with diabetes (16.4%) than in those with prediabetes (9.2%) or normoglycaemia (8.5%); hazard ratio (HR) for diabetes versus normoglycaemia 2.09 (95% CI 1.78-2.46, p<0.0001) and for diabetes versus prediabetes 1.90 (1.65-2.17, p<0.0001). Alirocumab resulted in similar relative reductions in the incidence of the primary endpoint in each glycaemic category, but a greater absolute reduction in the incidence of the primary endpoint in patients with diabetes (2.3%, 95% CI 0.4 to 4.2) than in those with prediabetes (1.2%, 0.0 to 2.4) or normoglycaemia (1.2%, -0.3 to 2.7; absolute risk reduction p(interaction) = 0.0019). Among patients without diabetes at baseline, 676 (10.1%) developed diabetes in the placebo group, compared with 648 (9.6%) in the alirocumab group; alirocumab did not increase the risk of new-onset diabetes (HR 1.00, 95% CI 0.89-1.11). HRs were 0.97 (95% CI 0.87-1.09) for patients with prediabetes and 1.30 (95% CI 0.93-1.81) for those with normoglycaemia (p(interaction) = 0.11).Interpretation After a recent acute coronary syndrome, alirocumab treatment targeting an LDL cholesterol concentration of 0.65-1.30 mmol/L produced about twice the absolute reduction in cardiovascular events among patients with diabetes as in those without diabetes. Alirocumab treatment did not increase the risk of new-onset diabetes. Copyright (C) 2019 Elsevier Ltd. All rights reserved.Cardiolog
Effect of Alirocumab on Lipoprotein(a) and Cardiovascular Risk After Acute Coronary Syndrome
BACKGROUND Lipoprotein(a) concentration is associated with cardiovascular events. Alirocumab, a proprotein convertase subtilisin/kexin type 9 inhibitor, lowers lipoprotein(a) and low-density lipoprotein cholesterol (LDL-C).OBJECTIVES A pre-specified analysis of the placebo-controlled ODYSSEY Outcomes trial in patients with recent acute coronary syndrome (ACS) determined whether alirocumab-induced changes in lipoprotein(a) and LDL-C independently predicted major adverse cardiovascular events (MACE).METHODS One to 12 months after ACS, 18,924 patients on high-intensity statin therapy were randomized to alirocumab or placebo and followed for 2.8 years (median). Lipoprotein(a) was measured at randomization and 4 and 12 months thereafter. The primary MACE outcome was coronary heart disease death, nonfatal myocardial infarction, ischemic stroke, or hospitalization for unstable angina.RESULTS Baseline lipoprotein(a) levels (median: 21.2 mg/dl; interquartile range [IQR]: 6.7 to 59.6 mg/dl) and LDL-C [corrected for cholesterol content in lipoprotein(a)] predicted MACE. Alirocumab reduced lipoprotein(a) by 5.0 mg/dl (IQR: 0 to 13.5 mg/dl), corrected LDL-C by 51.1 mg/dl (IQR: 33.7 to 67.2 mg/dl), and reduced the risk of MACE (hazard ratio [HR]: 0.85; 95% confidence interval [CI]: 0.78 to 0.93). Alirocumab-induced reductions of lipoprotein(a) and corrected LDL-C independently predicted lower risk of MACE, after adjustment for baseline concentrations of both lipoproteins and demographic and clinical characteristics. A 1-mg/dl reduction in lipoprotein(a) with alirocumab was associated with a HR of 0.994 (95% CI: 0.990 to 0.999; p = 0.0081).CONCLUSIONS Baseline lipoprotein(a) and corrected LDL-C levels and their reductions by alirocumab predicted the risk of MACE after recent ACS. Lipoprotein(a) lowering by alirocumab is an independent contributor to MACE reduction, which suggests that lipoprotein(a) should be an independent treatment target after ACS. (ODYSSEY Outcomes: Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab; NCT01663402) (C) 2020 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation.Cardiolog