Improvement in Renal Function and Reduction in Serum Uric Acid with Intensive Statin Therapy in Older Patients: A Post Hoc Analysis of the SAGE Trial.

BackgroundImprovement in renal function and decreases in serum uric acid (SUA) have been reported following prolonged high-intensity statin (HMG-CoA reductase inhibitor) therapy. This post hoc analysis of the SAGE trial examined the effect of intensive versus less intensive statin therapy on renal function, safety, and laboratory parameters, including SUA, in elderly coronary artery disease (CAD) patients (65-85 years) with or without chronic kidney disease (CKD).MethodsPatients were randomized to atorvastatin 80 mg/day or pravastatin 40 mg/day and treated for 12 months. Patients were stratified using Modification of Diet in Renal Disease (MDRD) estimated glomerular filtration rates (eGFRs) in CKD (eGFR <60 mL/min/1.73 m(2)) and non-CKD populations.ResultsOf the 893 patients randomized, 858 had complete renal data and 418 of 858 (49%) had CKD (99% Stage 3). Over 12 months, eGFR increased with atorvastatin and remained stable with pravastatin (+2.38 vs. +0.18 mL/min/1.73 m(2), respectively; p < 0.0001). MDRD eGFR improved significantly in both CKD treatment arms; however, the increased eGFR in patients without CKD was significantly greater with atorvastatin (+2.08 mL/min/1.73 m(2)) than with pravastatin (-1.04 mL/min/1.73 m(2)). Modest reductions in SUA were observed in both treatment arms, but a greater fall occurred with atorvastatin than with pravastatin (-0.52 vs. -0.09 mg/dL, p < 0.0001). Change in SUA correlated negatively with changes in eGFR and positively with changes in low-density lipoprotein cholesterol. Reports of myalgia were rare (3.6% CKD; 5.7% non-CKD), and there were no episodes of rhabdomyolysis. Elevated serum alanine and aspartate transaminase to >3 times the upper limit of normal occurred in 4.4% of atorvastatin- and 0.2% of pravastatin-treated patients.ConclusionIntensive management of dyslipidemia in older patients with stable coronary heart disease may have beneficial effects on renal function and SUA

A study o f single and two-phase flows in devices with narrow flow passages

In many industries, the depressurisation of gas-saturated solutionseis controlled to regulate bubble formation. Carbonated drink dispensers need to depressurise solutions with minimum bubble formation, whereas dissolved air flotation nozzles need to produce the maximum number of micro-bubbles. Four commercial carbonated drink dispensers were tested. The dispenser predicted to retain the most dissolved carbon dioxide at the outlet had a narrow annular gap of 0.1mm at the narrowest point. The pressure drop across this device varied linearly with water flow rate. When tested with two-phase air and water flow, the pressure drop decreased with increasing air flow at given water flowrates. This unusual behaviour was thought to be due to the narrow flow path. Carbon dioxide-saturated water tests supported these results as the pressure drop was found to be lower than the single-phase water tests. Thus under similar conditions, devices that create less turbulence would retain more dissolved gas. Flow in coils was investigated, as they have flow characteristics that were potentially suitable for carbonated drink dispensing. Compared to straight pipes, flow in coils remained laminar until higher Reynolds numbers. The friction factors were also higher in coils than straight pipes. Coils made from 0.0025m internal diameter polyurethane tubing were tested, with coil diameters of 0.029m, 0.079m and 0.139m and lengths of 2, 3, 3.7, 5 and 7m. A method of estimating the friction factors in coils by treating them as a series of 90° bends was proposed. The calculated results agreed with the present small tube experiments and with data from published literature for a range of tube diameters. At a given pressure drop, the shortest coil with the smallest coil diameter had the greatest dissolved gas concentration at the outlet and the highest flowrate. Furthermore, the concentration of dissolved gas at the coil outlet was greater than at the nozzle outlet.Ph

Risk of Major Complications From Coronary Angioplasty Performed Immediately After Diagnostic Coronary Angiography: Results From the Registry of the Society for Cardiac Angiography and Interventions

AbstractObjectives. This study was designed to determine the risk of performing percutaneous transluminal coronary angioplasty (PTCA) at the time of diagnostic catheterization (“combined procedures”).Background. Health care providers are under increasing pressure to combine diagnostic and interventional coronary procedures to reduce costs. However, the risk associated with combined procedures has not been rigorously assessed.Methods. A multicenter cohort study of 35,700 patients undergoing elective PTCA from 1992 through 1995 was performed to determine the risk of major complications (myocardial infarction, emergency coronary artery bypass graft surgery or death) from combined relative to staged procedures (i.e., performing PTCA at a session subsequent to diagnostic catheterization).Results. The risks of major complications from combined and staged procedures were 2.0% and 1.6%, respectively (unadjusted odds ratio [OR] 1.28, 95% confidence interval [CI] 1.05 to 1.57). After adjusting for clinical and angiographic differences and clustering by laboratory, the risk from combined procedures was not significantly elevated (multivariable OR 1.18, 95% CI 0.89 to 1.55). However, several subgroups of patients did have an increased risk from combined procedures: patients with multivessel disease (multivariable OR 1.64, 95% CI 1.13 to 2.39); women (multivariable OR 1.64, 95% CI 1.05 to 2.55); patients >65 years old (multivariable OR 1.40, 95% CI 1.02 to 1.93); and patients undergoing multilesion PTCA (multivariable OR 1.53, 95% CI 1.06 to 2.21). The risk of combined relative to staged procedures decreased over the 4-year period (multivariable p = 0.029).Conclusions. Combining PTCA with diagnostic catheterization appears to be safe in many patients. However, several subgroups of patients may be at increased risk. Careful patient selection will most likely remain critical to ensuring the safety of combined procedures.(J Am Coll Cardiol 1997;30:193–200

Visit-to-visit variability of lipid measurements as predictors of cardiovascular events.

BACKGROUND:Higher visit-to-visit variability in risk factors such as blood pressure and low-density lipoprotein (LDL)-cholesterol are associated with an increase in cardiovascular (CV) events. OBJECTIVE:The purpose of this study was to determine whether variability in high-density lipoprotein cholesterol (HDL-C) and triglyceride levels predicted coronary and CV events in a clinical trial population with known coronary disease. METHODS:We assessed intraindividual variability in fasting high-density lipoprotein (HDL)-cholesterol, triglyceride, and LDL-cholesterol measurements among 9572 patients in the Treating to New Targets trial and correlated the results with coronary events over a median follow-up of 4.9 years. RESULTS:In the fully adjusted Cox model, 1 standard deviation of average successive variability, defined as the average absolute difference between successive values, was associated with an increased risk of a coronary event for HDL-cholesterol (hazard ratio [HR] 1.16, 95% confidence interval [CI] 1.11-1.21, P < .0001), for triglycerides (HR 1.09, 95% CI 1.04-1.15, P = .0005), and for LDL-cholesterol (HR 1.14, 95% CI 1.09-1.19, P < .0001). Similar results were found for the 3 other measures of variability, standard deviation, coefficient of variability, and variability independent of the mean. Similar results were seen for CV events, stroke, and nonfatal myocardial infarction. Higher variability in triglyceride and LDL-cholesterol, but not HDL-cholesterol, was predictive of incident diabetes. The correlation among the variability of the 3 lipid measurements was weak. CONCLUSION:Visit-to-visit variability in fasting measurements of HDL-cholesterol, triglycerides, and LDL-cholesterol are predictive of coronary events, CV events, and for triglyceride and low-density lipoprotein cholesterol variability, incident diabetes. The mechanisms accounting for these associations remain to be determined

An Estimate of Avian Mortality at Communication Towers in the United States and Canada

Avian mortality at communication towers in the continental United States and Canada is an issue of pressing conservation concern. Previous estimates of this mortality have been based on limited data and have not included Canada. We compiled a database of communication towers in the continental United States and Canada and estimated avian mortality by tower with a regression relating avian mortality to tower height. This equation was derived from 38 tower studies for which mortality data were available and corrected for sampling effort, search efficiency, and scavenging where appropriate. Although most studies document mortality at guyed towers with steady-burning lights, we accounted for lower mortality at towers without guy wires or steady-burning lights by adjusting estimates based on published studies. The resulting estimate of mortality at towers is 6.8 million birds per year in the United States and Canada. Bootstrapped subsampling indicated that the regression was robust to the choice of studies included and a comparison of multiple regression models showed that incorporating sampling, scavenging, and search efficiency adjustments improved model fit. Estimating total avian mortality is only a first step in developing an assessment of the biological significance of mortality at communication towers for individual species or groups of species. Nevertheless, our estimate can be used to evaluate this source of mortality, develop subsequent per-species mortality estimates, and motivate policy action