Mary Tan

Validation of the Global Registry of Acute Coronary Event (GRACE) risk score for in-hospital mortality in patients with acute coronary syndrome in Canada

BACKGROUND The Global Registry of Acute Coronary Event (GRACE) risk score was developed in a large multinational registry to predict in-hospital mortality across the broad spectrum of acute coronary syndromes (ACS). Because of the substantial regional variation and temporal changes in patient characteristics and management patterns, we sought to validate this risk score in a contemporary Canadian population with ACS. METHODS The main GRACE and GRACE(2) registries are prospective, multicenter, observational studies of patients with ACS (June 1999 to December 2007). For each patient, we calculated the GRACE risk score and evaluated its discrimination and calibration by the c statistic and the Hosmer-Lemeshow goodness-of-fit test, respectively. To assess the impact of temporal changes in management on the GRACE risk score performance, we evaluated its discrimination and calibration after stratifying the study population into prespecified subgroups according to enrollment period, type of ACS, and whether the patient underwent coronary angiography or revascularization during index hospitalization. RESULTS A total of 12,242 Canadian patients with ACS were included; the median GRACE risk score was 127 (25th and 75th percentiles were 103 and 157, respectively). Overall, the GRACE risk score demonstrated excellent discrimination (c statistic 0.84, 95% CI 0.82-0.86, P < .001) for in-hospital mortality. Similar results were seen in all the subgroups (all c statistics >/=0.8). However, calibration was suboptimal overall (Hosmer-Lemeshow P = .06) and in various subgroups. CONCLUSIONS GRACE risk score is a valid and powerful predictor of adverse outcomes across the wide range of Canadian patients with ACS. Its excellent discrimination is maintained despite advances in management over time and is evident in all patient subgroups. However, the predicted probability of in-hospital mortality may require recalibration in the specific health care setting and with advancements in treatment.

Contemporary Trends in the Diagnosis and Management of Pulmonary Arterial Hypertension: An Initiative to Close the Care Gap

BACKGROUND The Pulmonary Arterial Hypertension-Quality Enhancement Research Initiative (PAHQuERI) was created to help clinicians to implement a guidelines-based approach to the diagnosis and management of pulmonary arterial hypertension (PAH). Patients with PAH represent a heterogeneous population, and physician evaluation and treatment paradigms may vary considerably. METHODS Using an electronic data management system, participating physicians recorded data on diagnostic workup, disease management, and outcomes of patients with PAH. Queries were generated automatically following each follow-up visit if the tests recommended by the American College of Chest Physicians (ACCP) were not performed at least once. RESULTS Of 791 patients enrolled in PAH-QuERI, 77% were women; 64% received a diagnosis . 3 months prior to enrollment; 9% were in New York Heart Association functional class I, 39% in II, 48% in III, and 5% in IV; and the median age was 55 years (interquartile range, 45-66 years). At enrollment, all ACCP-recommended tests had been performed in only 6% of patients. The automated program generated 1,530 reminders for 642 patients (81%) with validated enrollment data. The proportion of recommended tests performed was 91% for CBC count, 91% for liver function test, 50% for connective tissue disease screen, 29% for HIV screen, 88% for chest radiograph, 82% for ECG, 97% for two-dimensional echocardiogram, 83% for pulmonary function tests, 41% for oximetry, 57% for ventilation/perfusion scan, 79% for 6-min walk distance, and 90% for right-sided heart catheterization. Regarding management, 78% of patients were on disease specific therapy, and the use of these therapies tended to increase with the functional disability of the patient. One hundred seventy patients were taking calcium channel blockers, 91 specifically for PAH. Only six of 91 patients (7%) who received calcium channel blockers specifically for PAH had met the current guideline for acute vasoreactivity. CONCLUSIONS When comparing reported clinical practice with ACCP guidelines-recommended strategies, a diagnostic care gap is apparent such that certain essential and recommended diagnostic tests may be underused despite the availability of detailed guidelines and reminders.

Original ResearchPulmonary Vascular DiseaseContemporary Trends in the Diagnosis and Management of Pulmonary Arterial Hypertension: An Initiative to Close the Care Gap

BACKGROUND The Pulmonary Arterial Hypertension-Quality Enhancement Research Initiative (PAHQuERI) was created to help clinicians to implement a guidelines-based approach to the diagnosis and management of pulmonary arterial hypertension (PAH). Patients with PAH represent a heterogeneous population, and physician evaluation and treatment paradigms may vary considerably. METHODS Using an electronic data management system, participating physicians recorded data on diagnostic workup, disease management, and outcomes of patients with PAH. Queries were generated automatically following each follow-up visit if the tests recommended by the American College of Chest Physicians (ACCP) were not performed at least once. RESULTS Of 791 patients enrolled in PAH-QuERI, 77% were women; 64% received a diagnosis . 3 months prior to enrollment; 9% were in New York Heart Association functional class I, 39% in II, 48% in III, and 5% in IV; and the median age was 55 years (interquartile range, 45-66 years). At enrollment, all ACCP-recommended tests had been performed in only 6% of patients. The automated program generated 1,530 reminders for 642 patients (81%) with validated enrollment data. The proportion of recommended tests performed was 91% for CBC count, 91% for liver function test, 50% for connective tissue disease screen, 29% for HIV screen, 88% for chest radiograph, 82% for ECG, 97% for two-dimensional echocardiogram, 83% for pulmonary function tests, 41% for oximetry, 57% for ventilation/perfusion scan, 79% for 6-min walk distance, and 90% for right-sided heart catheterization. Regarding management, 78% of patients were on disease specific therapy, and the use of these therapies tended to increase with the functional disability of the patient. One hundred seventy patients were taking calcium channel blockers, 91 specifically for PAH. Only six of 91 patients (7%) who received calcium channel blockers specifically for PAH had met the current guideline for acute vasoreactivity. CONCLUSIONS When comparing reported clinical practice with ACCP guidelines-recommended strategies, a diagnostic care gap is apparent such that certain essential and recommended diagnostic tests may be underused despite the availability of detailed guidelines and reminders.

Optimal Medical Therapy for Non–ST-Segment–Elevation Acute Coronary Syndromes Exploring Why Physicians Do Not Prescribe Evidence-Based Treatment and Why Patients Discontinue Medications After Discharge

Background—Acute coronary syndrome (ACS) patients in the highest risk categories are least likely to receive evidence-based treatments (EBTs). We sought to determine why physicians do not prescribe EBTs for patients with non–ST-segment–elevation ACSs and the factors determining use of these treatments after 1 year. Methods and Results—One thousand nine hundred fifty-six non–ST-segment-elevation ACS patients were enrolled in the prospective, multicenter Canadian ACS registry II between October 2002 and December 2003. Each patients physician gave reasons why guideline-indicated medication(s) was not prescribed during hospitalization. Medication use and reason(s) for discontinuation after 1 year were obtained by telephone interview of the patients. The commonest reason for not prescribing EBTs was “not high-enough risk” or “no evidence/guidelines to support use.” However, Global Registry of Acute Coronary Events scores of patients not treated for this reason were often similar to or higher than those of patients prescribed such treatment. After 1 year, 77% of patients not on optimal ACS treatment at discharge remained without optimal treatment, and overall antiplatelet, &bgr;-blocker, and angiotensin-converting enzyme inhibitor use declined. Approximately one third of patients not taking EBTs had stopped their medication without instruction from their doctor. Conclusions—Nonprovision of EBTs may be due to subjective underestimation of patient risk and hence, likely treatment benefit. Oversights in care delivery were also apparent. Objective risk stratification, combined with efforts to ensure provision and adherence to EBTs, should be encouraged.

Paradoxical use of invasive cardiac procedures for patients with non-ST segment elevation myocardial infarction: An international perspective from the CRUSADE Initiative and the Canadian ACS Registries I and II

BACKGROUND Practice guidelines support an early invasive strategy in patients with non-ST segment elevation acute coronary syndromes, particularly in those at higher risk. OBJECTIVES To compare North American rates of invasive cardiac procedure use stratified by risk. METHODS Use of invasive cardiac procedures and other care patterns in patients with non-ST segment elevation acute coronary syndromes from the United States (US) Can Rapid risk stratification of Unstable angina patients Suppress ADverse outcomes with Early implementation of the ACC/AHA guidelines (CRUSADE) National Quality Improvement Initiative (n=88,097; 465 hospitals) and Canadian ACS Registries I (n=1270; 51 hospitals) and II (n=1473; 36 hospitals) were compared after dividing patients into different risk categories based on predicted risk of in-hospital mortality. RESULTS While the overall use of invasive procedures was higher in the US, high-risk patients were least likely to undergo coronary angiography (41% versus 64% in Canada [P<0.0001] and 53% versus 76% in the United States [P<0.0001]) and percutaneous coronary intervention (14% versus 32% in Canada [P<0.0001] and 28% versus 51% in the US [P<0.0001]) compared with low-risk patients in both countries, and had longer median waiting times for these procedures (120 h versus 96 h in Canada [P<0.0001] and 34 h versus 23 h in the US [P<0.0001] for coronary angiography). CONCLUSIONS The inverse relationship between risk level and the use of invasive cardiac procedures for patients in the US and Canada suggests that a risk stratification-guided approach for triaging patients to an early invasive management strategy is paradoxically used. This incongruous relationship holds true regardless of resource availability or overall rates of cardiac catheterization.

The pulmonary arterial hypertension quality enhancement research initiative: comparison of patients with idiopathic PAH to patients with systemic sclerosis-associated PAH

Objective The objective of this report is to compare baseline, management and survival characteristics in idiopathic pulmonary arterial hypertension (IPAH) with systemic sclerosis-associated pulmonary arterial hypertension (SSc-APAH) using data from the prospectively enrolled PAH Quality Enhancement Research Initiative. Methods Between August 2005 and July 2007, patients with IPAH and SSc-APAH were enrolled across 60 US sites and followed up for 3 years. Data on diagnostic tests, clinical variables, pulmonary arterial hypertension (PAH) medication and outcomes were recorded. Results With some exceptions, baseline clinical and laboratory characteristics were similar between the 279 patients with IPAH and the 228 with SSc-APAH. Patients with SSc-APAH were older at the time of PAH diagnosis, were more likely to be female and were antinuclear antibody positive. Patients with SSc-APAH had poorer spirometric results. During the 3-year follow-up, both groups were managed with prostacyclin and prostacyclin analogue treatment, endothelin receptor antagonists and phosphodiesterase type 5 inhibitors (PDE5i) singly or in combination. At 3 years, patients with SSc-APAH were more likely to be treated with PDE5i alone or with an endothelin receptor antagonist. Patients with SSc-APAH had a significantly lower survival rate compared to patients with IPAH (60% vs 77%, p<0.0001). Conclusions The cohort with SSc-APAH was older, was more severely ill, was more likely to be female, was managed with PDE5i and had reduced 3-year survival compared with the cohort with IPAH.

Relationship between risk stratification at admission and treatment effects of early invasive management following fibrinolysis: insights from the Trial of Routine ANgioplasty and Stenting After Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction (TRANSFER-AMI)

AIMS We sought to determine the effectiveness of early routine percutaneous coronary intervention (PCI) post-fibrinolysis for ST-elevation myocardial infarction (STEMI) in relation to baseline risk status. METHODS AND RESULTS In this post hoc subgroup analysis of Trial of Routine Angioplasty and Stenting after Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction (TRANSFER-AMI), we stratified 1059 STEMI patients receiving tenecteplase into low-intermediate [Global Registry of Acute Coronary Events (GRACE) risk score<155; n=889] vs. high-risk (GRACE risk score ≥155; n=170) groups, based on the GRACE risk score for in-hospital mortality. There was a significant interaction between treatment assignment and risk status for the composite endpoint of death/re-MI at 30 days (P for interaction<0.001). Compared with the standard treatment, pharmacoinvasive therapy (early routine PCI) was associated with a lower rate of death/re-MI at 30 days in the low-intermediate risk stratum (8.1 vs. 2.9%, P<0.001), but a higher rate of death/re-MI in the high-risk group (13.8 vs. 27.8%, P=0.025). We found similar heterogeneity in the treatment effects on 30-day mortality and death/re-MI at 1 year (P for interaction=0.008 and 0.001, respectively), when the GRACE risk score was analysed as a continuous variable (P for interaction<0.001) and when patients were stratified by the Thrombolysis In Myocardial Infarction (TIMI) risk score (P for interaction=0.001). CONCLUSION We observed a strong heterogeneity in the treatment effects of a pharmacoinvasive strategy after fibrinolysis for STEMI, which is associated with improved outcomes only among patients with a low-intermediate GRACE risk score. Conversely, the early invasive strategy is associated with worse outcomes in high-risk patients. These novel findings should be considered exploratory only and require confirmation in other trials and meta-analyses. CLINICAL TRIAL REGISTRATION INFORMATION http://www.clinicaltrials.gov/ct2/show/NCT00164190 ClinicalTrials.gov number, NCT00164190.

Treatment and one-year outcome of patients with renal dysfunction across the broad spectrum of acute coronary syndromes.

BACKGROUND There are limited data on the treatment and long-term outcome of patients with renal dysfunction across the broad spectrum of acute coronary syndromes (ACS) in Canada. OBJECTIVES To examine the treatment patterns and outcome of ACS patients with renal dysfunction. METHODS In the prospective, multicentre, Canadian ACS Registry, 3510 patients hospitalized for ACS (including unstable angina, ST and non-ST elevation myocardial infarction) were categorized into four groups: normal renal function (creatinine clearance [CrCl] 90 mL/min or greater; n=1152), mild renal dysfunction (CrCl 60 mL/min to 89 mL/min; n=1253), moderate renal dysfunction (CrCl 30 mL/min to 59 mL/min; n=944) and severe renal dysfunction (CrCl less than 30 mL/min; n=161). Multivariable logistic regression analysis was performed to examine the independent prognostic value of renal dysfunction, and the association of various therapies with one-year survival. RESULTS All-cause mortality at one year was 2.8%, 6.4%, 14.5% and 40.9% in patients with normal renal function, and mild, moderate and severe renal dysfunction, respectively (P for trend<0.001). After adjusting for other prognosticators, moderate (OR 1.82, 95% CI 1.08 to 3.08) and severe (OR 6.29, 95% CI 3.37 to 11.77) renal dysfunction remained independent predictors of one-year death. Patients with renal dysfunction were less likely to receive fibrinolytic therapy, to undergo coronary angiography and revascularization in hospital, and to be treated with acetylsalicylic acid, beta-blockers and lipid-lowering therapy at discharge and at one-year follow-up. The association of in-hospital revascularization, and discharge use of acetylsalicylic acid and beta-blockers with better one-year survival was similar among patients with normal and impaired renal function. CONCLUSIONS Renal dysfunction is prevalent and independently predicts higher mortality in patients with ACS. The current underutilization of effective therapies may contribute to the poor outcome. There remains an important opportunity to improve care in this high-risk population.

Relation Between Obesity and the Attainment of Optimal Blood Pressure and Lipid Targets in High Vascular Risk Outpatients

Obesity is associated with hypertension, dyslipidemia, and diabetes, but it is also an independent cardiovascular risk factor. We sought to evaluate the differences in treatment patterns and attainment of guideline-recommended targets among high-risk vascular outpatients in relation to their body mass index (BMI). The prospective Vascular Protection and Guideline Orientated Approach to Lipid Lowering Registries recruited 7,357 high-risk vascular outpatients in Canada from 2001 to 2004. We stratified the patient population into 3 groups according to their BMI: normal weight (BMI <24.9 kg/m²), overweight (BMI 25 to 29.9 kg/m²), and obese (BMI >30 kg/m²). We evaluated the rates of attainment for contemporary guideline targets of blood pressure (<140/90 or <130/80 mm Hg in the presence of diabetes) and lipids (low-density lipoprotein [LDL] <2.5 mmol/L [96.7 mg/dl] and total cholesterol [TC]/high-density lipoprotein [HDL] ratio <4.0). Of the 7,357 patients, 1,305 (17.7%) were normal weight, 2,791 (37.9%) overweight, and 3,261 (44.4%) obese, as determined by the BMI. Obese patients were younger and more likely to have hypertension and diabetes (all p <0.001 for trend). Obese patients had higher baseline blood pressure, TC, LDL cholesterol, triglyceride levels and TC/HDL ratio, and lower HDL cholesterol. Obese patients were more likely to be treated with antihypertensive agents (p = 0.002), angiotensin-converting enzyme inhibitors (p = 0.024), angiotensin receptor blockers (p <0.001), and high-dose statin therapy (p = 0.001). On multivariable analyses, obese patients were less likely to attain the blood pressure (odds ratio 0.77, 95% confidence interval 0.66 to 0.90, p = 0.001) and TC/HDL ratio (odds ratio 0.48, 95% confidence interval 0.42 to 0.55, p <0.001) targets but not the LDL targets (odds ratio 0.89, 95% confidence interval 0.78 to 1.03, p = 0.11). In conclusion, only a minority ambulatory patients at high cardiovascular risk achieved both guideline-recommended blood pressure and lipid targets, and this significant treatment gap was more pronounced among obese patients. Our findings underscore the opportunity to optimize the treatment of these high-risk patients.

Treatment-resistant depression in primary care across Canada.

Objective: Treatment-resistant depression (TRD) represents a considerable global health concern. The goal of the InSight study was to investigate the prevalence of TRD and to evaluate its clinical characterization and management, compared with nonresistant depression, in primary care centres. Methods: Physicians completed a case report on a consecutive series of patients with major depressive disorder (n = 1212), which captured patient demographics and comorbidity, as well as current and past medication. Results: Using failure to respond to at least 2 antidepressants (ADs) from different classes as the definition of TRD, the overall prevalence was 21.7%. There were no differences in prevalence between men and women or among ethnicities. Patients with TRD had longer episode duration, were more likely to receive polypharmacy (for example, psychotropic, lipid-lowering, and antiinflammatory agents), and reported more AD related side effects. Higher rates of disability and comorbidity (axes I to III) were associated with treatment resistance. Obesity and being overweight were also associated with treatment resistance. While the selection and sequencing of pharmacotherapy by family physicians in this sample was in line with recommendations from evidence-based treatment guidelines, the wait time to make a change in treatment was 6 to 8 weeks in both groups, which exceeds guideline recommendations. Conclusions: These real-world data demonstrate the high prevalence of TRD in primary care settings, and underscore the substantial burden of illness associated with TRD.