Christian Janssen

Chronic kidney injury in patients after cardiac catheterisation or percutaneous coronary intervention: a comparison of radial and femoral approaches (from the British Columbia Cardiac and Renal Registries)

Background Acute kidney injury (AKI) is a well-recognised complication of cardiac catheterisation and percutaneous coronary intervention (PCI). However, the incidence of chronic kidney disease (CKD) after catheterisation and PCI has not been fully evaluated. A number of risk factors have been implicated in the development of AKI following cardiac catheterisation. Transradial access could lead to a lower incidence of CKD after catheterisation or PCI because of less catheter contact with aortic atheroma, and reduced potential for atheroembolism. Objective To determine the incidence of CKD onset and its association with arterial access in patients after cardiac catheterisation or PCI. Methods and results Linkages between the British Columbia (BC) Cardiac Registry (N=69 214) patients who underwent catheterisation or PCI between 1999 and 2005 and the BC Renal Database were determined. Within 6 months after the cardiac procedure 0.4% of patients developed dialysis dependency, 0.2% in the transradial versus 0.4% in the transfemoral group (p<0.0001); 0.3% of patients developed stage 4 or 5 CKD, 0.1% in the transradial versus 0.4% in the transfemoral group (p<0.0001); 0.9% of patients developed new CKD, 0.2% in the transradial versus 1.2% in the transfemoral group (p<0.0001). After adjusting for baseline characteristics the femoral access site had an OR of 4.36 (95% CI 2.48 to 7.66) for the development of the composite end point of new dialysis, new stage 4 or 5 CKD or new CKD. Conclusions In this large database of current practice coronary catheterisation and PCI, the incidence of CKD onset within 6 months of the procedure was 0.9%. The transradial access site is associated with less CKD than the femoral approach.

Red blood cell storage duration and mortality in patients undergoing percutaneous coronary intervention.

BACKGROUND Blood transfusion has been associated with an increased mortality in patients undergoing percutaneous coronary intervention (PCI). Although the reasons for this remain unclear, it may be related to the structural and functional changes occurring within red blood cells (RBCs) during storage. We investigated whether RBC storage duration was associated with mortality in patients requiring transfusion after PCI. METHODS We collected data on all RBC transfusions occurring within 10 days of PCI (excluding those related to cardiac surgery) using the British Columbia Cardiac Registry and Central Transfusion Registry. Transfusion details were analyzed according to 30-day survival. RESULTS From a total of 32,580 patients undergoing PCI, 909 (2.8%) patients received RBCs with a mean storage duration of 25 +/- 10 days. In these 909 patients, mean transfusion volumes were lower in survivors (2.8 +/- 2.1 vs 3.8 +/- 2.9 U, P = .002) than those who died within 30 days. In a multivariate analysis to adjust for baseline risk, mean RBC storage age (HR 1.02 [95% CI 1.01-1.04], P = .002) and transfusion volume (HR 1.26 [95% CI 1.18-1.34], P < .001) both predicted 30-day mortality. Transfused patients who received only older blood (RBC min age >28 days) appeared to be at greater risk of death (HR 2.49 [95% CI 1.45-4.25], P = .001). CONCLUSION Red blood cell transfusion is associated with increased 30-day mortality in patients undergoing PCI. Although current transfusion practice permits RBC storage for up to 42 days, the use of older red cells may pose an additional hazard to this patient group.

Real estate price prediction under asymmetric loss

This paper deals with the problem of how to adjust a predictive mean in a practical situation of prediction where there is asymmetry in the loss function. A standard linear model is considered for predicting the price of real estate using a normal-gamma conjugate prior for the parameters. The prior of a subject real estate agent is elicited but, for comparison, a diffuse prior is also considered. Three loss functions are used: asymmetric linear, asymmetric quadratic and LINEX, and the parameters under each of these postulated forms are elicited. Theoretical developments for prediction under each loss function in the presence of normal errors are presented and useful tables of adjustment factor values given. Predictions of the dependent price variable for two properties with differing characteristics are made under each loss function and the results compared.

TARGET SELECTION IN PROCESS CONTROL UNDER ASYMMETRIC COSTS

Many production processes require specific control variables to be kept at preset values. The variables are often subject to random influences and being off-target is generally associated with costs. The great majority of papers in this area have consid..

Non-red blood cell transfusion as a risk factor for mortality following percutaneous coronary intervention

BACKGROUND Bleeding following percutaneous coronary intervention (PCI) is common and may lead to transfusion and death. Although previous work has examined the effect of red blood cell (RBC) transfusion in patients with coronary disease, no study had investigated whether transfusion of non-RBC components was associated with mortality following PCI. METHODS All subjects transfused in the 10 days following PCI were identified using the British Columbia Cardiac and Central Transfusion Registries. Patients undergoing cardiac surgery following PCI were excluded as transfusion was assumed to be due to surgical related bleeding. Transfusion products were categorised as RBC and non-RBC comprising platelets, plasma and cryoprecipitate. Blood product use was compared according to thirty day mortality using multivariate regression and propensity adjustment for confounding variables. RESULTS From a total of 32,580 patients who underwent PCI, 952 patients received at least 1 blood product within 10 days of PCI. Non-RBC transfusion occurred more commonly in the cohort of transfused patients dying within 30 days (p<0.001). After adjustment for baseline risk, transfusion of plasma/cryoprecipitate (HR 5.17; 95% C.I. 2.87-9.32, p<0.001) and platelets (HR 2.13; 95% C.I. 1.10-4.13, p=0.03) was associated with increased 30 day mortality. In a propensity risk adjusted model, transfusion of plasma/cryoprecipitate and RBC transfusion volume remained as significant predictors of 30-day mortality (p<0.001). CONCLUSIONS Transfusion following PCI appears to be associated with an increased risk of death within 30 days. We now report that transfusion with plasma rich non-RBC products may confer an additional mortality risk to patients undergoing PCI.

Delay in Filling First Clopidogrel Prescription After Coronary Stenting Is Associated With an Increased Risk of Death and Myocardial Infarction

Background Patients frequently experience difficulties with medication compliance after hospital discharge. We investigated the effect of a delay in filling a first clopidogrel prescription after hospital discharge on clinical outcomes subsequent to coronary stenting. Methods and Results Hospital administrative, community pharmacy, and cardiac revascularization data were determined for all patients receiving a coronary stent in British Columbia 2004–2006 with follow‐up out to 2 years. Coxs proportional hazard regression analysis, adjusting for baseline demographics and procedural variables, was performed to examine the effects of delay in filling a clopidogrel prescription after hospital discharge on clinical outcomes. Of 15 629 patients treated with coronary stents, 3599 received at least 1 drug‐eluting stent (DES), whereas 12 030 received bare metal stents (BMS) alone. In total, 1064 (30%) and 3758 (31%) patients in the DES and BMS groups, respectively, failed to fill a prescription within 3 days of discharge (median, 1 day; interquartile range [IQR], 1 to 3). After regression analysis, a delay of >3 days was predictive of mortality and recurrent myocardial infarction (MI) irrespective of stent type (DES: hazard ratio [HR], 2.4; 95% confidence interval [CI], 1.7 to 3.4; and HR, 2.0; 95% CI, 1.5 to 2.7, respectively, and BMS: HR, 2.2; 95% CI, 1.9 to 2.6; and HR, 1.8; 95% CI, 1.5 to 2.1, respectively). This excess hazard was greatest in the 30‐day period immediately after hospital discharge (mortality: HR, 5.5; 95% CI, 3.5 to 8.6; and MI: HR, 3.1; 95% CI, 2.4 to 4.0, for all patients). Conclusions Delays in patients filling their first prescription for clopidogrel after coronary stenting are common and associated with adverse clinical outcomes, irrespective of stent type. Strategies to reduce delays have the potential to improve clinical outcomes.

NON-ADHERENCE WITH CLOPIDOGREL AFTER CORONARY STENTING IS ASSOCIATED WITH INCREASED MORTALITY AND MYOCARDIAL INFARCTION

Non-adherence with clopidogrel after coronary stenting may be associated with an adverse outcome. We analysed province-wide data to establish if non-adherence with clopidogrel was associated with death or MI. We linked provincial registries to determine clopidogrel use and outcomes for patients