Moira K. Kapral

Relation between age and cardiovascular disease in men and women with diabetes compared with non-diabetic people: a population-based retrospective cohort study

BACKGROUND Adults with diabetes are thought to have a high risk of cardiovascular disease (CVD), irrespective of their age. The main aim of this study was to find out the age at which people with diabetes develop a high risk of CVD, as defined by: an event rate equivalent to a 10-year risk of 20% or more; or an event rate equivalent to that associated with previous myocardial infarction. METHODS We did a population-based retrospective cohort study using provincial health claims to identify all adults with (n=379,003) and (n=9,018,082) without diabetes mellitus living in Ontario, Canada, on April 1, 1994. Individuals were followed up to record CVD events until March 31, 2000. FINDINGS The transition to a high-risk category occurred at a younger age for men and women with diabetes than for those without diabetes (mean difference 14.6 years). For the outcome of acute myocardial infarction (AMI), stroke, or death from any cause, diabetic men and women entered the high-risk category at ages 47.9 and 54.3 years respectively. When we used a broader definition of CVD that also included coronary or carotid revascularisation, the ages were 41.3 and 47.7 years for men and women with diabetes respectively. INTERPRETATION Diabetes confers an equivalent risk to ageing 15 years. However, in general, younger people with diabetes (age 40 or younger) do not seem to be at high risk of CVD. Age should be taken into account in targeting of risk reduction in people with diabetes.

Atrial Fibrillation in Patients with Cryptogenic Stroke

BACKGROUND Atrial fibrillation is a leading preventable cause of recurrent stroke for which early detection and treatment are critical. However, paroxysmal atrial fibrillation is often asymptomatic and likely to go undetected and untreated in the routine care of patients with ischemic stroke or transient ischemic attack (TIA). METHODS We randomly assigned 572 patients 55 years of age or older, without known atrial fibrillation, who had had a cryptogenic ischemic stroke or TIA within the previous 6 months (cause undetermined after standard tests, including 24-hour electrocardiography [ECG]), to undergo additional noninvasive ambulatory ECG monitoring with either a 30-day event-triggered recorder (intervention group) or a conventional 24-hour monitor (control group). The primary outcome was newly detected atrial fibrillation lasting 30 seconds or longer within 90 days after randomization. Secondary outcomes included episodes of atrial fibrillation lasting 2.5 minutes or longer and anticoagulation status at 90 days. RESULTS Atrial fibrillation lasting 30 seconds or longer was detected in 45 of 280 patients (16.1%) in the intervention group, as compared with 9 of 277 (3.2%) in the control group (absolute difference, 12.9 percentage points; 95% confidence interval [CI], 8.0 to 17.6; P<0.001; number needed to screen, 8). Atrial fibrillation lasting 2.5 minutes or longer was present in 28 of 284 patients (9.9%) in the intervention group, as compared with 7 of 277 (2.5%) in the control group (absolute difference, 7.4 percentage points; 95% CI, 3.4 to 11.3; P<0.001). By 90 days, oral anticoagulant therapy had been prescribed for more patients in the intervention group than in the control group (52 of 280 patients [18.6%] vs. 31 of 279 [11.1%]; absolute difference, 7.5 percentage points; 95% CI, 1.6 to 13.3; P=0.01). CONCLUSIONS Among patients with a recent cryptogenic stroke or TIA who were 55 years of age or older, paroxysmal atrial fibrillation was common. Noninvasive ambulatory ECG monitoring for a target of 30 days significantly improved the detection of atrial fibrillation by a factor of more than five and nearly doubled the rate of anticoagulant treatment, as compared with the standard practice of short-duration ECG monitoring. (Funded by the Canadian Stroke Network and others; EMBRACE ClinicalTrials.gov number, NCT00846924.).

Potentially Preventable Strokes in High-Risk Patients With Atrial Fibrillation Who Are Not Adequately Anticoagulated

Background and Purpose— Warfarin is the most effective stroke prevention medication for high-risk individuals with atrial fibrillation, yet it is often underused. This study examined the magnitude of this problem in a large contemporary, prospective stroke registry. Methods— We analyzed data from the Registry of the Canadian Stroke Network, a prospective database of consecutive patients with stroke admitted to 12 designated stroke centers in Ontario (2003 to 2007). We included patients admitted with an acute ischemic stroke who (1) had a known history of atrial fibrillation; (2) were classified as high risk for systemic emboli according to published guidelines; and (3) had no known contraindications to anticoagulation. Primary end points were the use of prestroke antithrombotic medications and admission international normalized ratio. Results— Among patients admitted with a first ischemic stroke who had known atrial fibrillation (n=597), strokes were disabling in 60% and fatal in 20%. Preadmission medications were warfarin (40%), antiplatelet therapy (30%), and no antithrombotics (29%). Of those taking warfarin, three fourths had a subtherapeutic international normalized ratio (<2.0) at the time of stroke admission. Overall, only 10% of patients with acute stroke with known atrial fibrillation were therapeutically anticoagulated (international normalized ratio ≥2.0) at admission. In stroke patients with a history of atrial fibrillation and a previous transient ischemic attack or ischemic stroke (n=323), only 18% were taking warfarin with therapeutic international normalized ratio at the time of admission for stroke, 39% were taking warfarin with subtherapeutic international normalized ratio, and 15% were on no antithrombotic therapy. Conclusions— In high-risk patients with atrial fibrillation admitted with a stroke, and who were candidates for anticoagulation, most were either not taking warfarin or were subtherapeutic at the time of ischemic stroke. Many were on no antithrombotic therapy. These findings should encourage greater efforts to prescribe and monitor appropriate antithrombotic therapy to prevent stroke in individuals with atrial fibrillation.

Sex Differences in Stroke Care and Outcomes Results From the Registry of the Canadian Stroke Network

Background— Stroke is an important cause of death and disability in women as well as men. However, little is known about sex differences in stroke care and outcomes. Methods— The Registry of the Canadian Stroke Network (RCSN) captured data on patients with stroke seen at acute care hospitals across Canada. We used data from phase 1 (July 2001 to February 2002) and phase 2 (June to December 2002) of the RCSN to compare stroke presentation, management, and 6-month outcomes in women and men using multivariable regression techniques to adjust for age and other factors. Results— The study sample included 3323 patients, with 1527 women. Stroke symptoms at presentation were similar in women and men, except that women were more likely to present with headaches and were less likely to have brain stem or cerebellar symptoms. There were no sex differences in the use of neuroimaging, thrombolysis, antithrombotic therapy, or consultations. Women were less likely than men to receive care on an acute stroke unit, but this difference was no longer significant after adjustment for age and other factors. Women were more likely than men to be discharged to long-term care and had greater disability at 6 months. Mortality and quality of life at 6 months were similar in women and men. Conclusions— Among patients participating in the RCSN, there were no major sex differences in stroke presentation or management. Compared with men, women were more often institutionalized and had a slightly worse functional status at 6 months after stroke.

Sex Differences and Similarities in the Management and Outcome of Stroke Patients

BACKGROUND AND PURPOSE Previous studies have documented sex differences in the management and outcome of patients with cardiovascular disease. However, little data exist on whether similar sex differences exist in stroke patients. We conducted a study to determine whether sex differences exist in patients with acute stroke admitted to Ontario hospitals. METHODS Using linked administrative databases, we performed a population-based cohort study. The databases contained information on all 44 832 patients discharged from acute-care hospitals in Ontario between April 1993 and March 1996 with a most responsible diagnosis of acute stroke. The main outcomes measured consisted of sex differences in comorbidities, the use of rehabilitative services, the use of antiplatelet therapy and anticoagulants (in elderly stroke survivors aged > or =65 years only), discharge destination, and mortality. RESULTS Male stroke patients were more likely than female stroke patients to have a history of ischemic heart disease (18.1% versus 15.3%, respectively; P<0.001) and diabetes mellitus (20.1% versus 18. 7%, respectively; P<0.001), whereas female patients were more likely than male patients to have hypertension (33.8% versus 30.0%, respectively; P<0.001) and atrial fibrillation (12.9% versus 10.2%, respectively; P<0.001). There were no sex differences in the usage of in-hospital rehabilitative services. The overall 90-day postdischarge use of aspirin and ticlopidine was similar in stroke survivors aged 65 to 84 years. However, among stroke survivors aged > or =85 years, men were more likely than women to receive aspirin (36. 0% versus 30.7%, respectively; P<0.001) and ticlopidine (9.2% versus 6.8%, respectively; P=0.007). Use of warfarin was similar for the two sexes. Men were more likely than women to be discharged home (50. 6% versus 40.9%, respectively; P<0.001) and less likely to be discharged to chronic care facilities (16.8% versus 25.2%, respectively; P<0.001). The risk of death 1 year after stroke was somewhat lower in women than men (adjusted odds ratio 0.939, 95% CI 0.899 to 0.980; P=0.004). The mortality differences were greatest among elderly stroke patients. CONCLUSIONS Elderly men are more likely than elderly women to receive aspirin and ticlopidine and equally like to receive warfarin after a stroke. Despite these differences, elderly women have a better 1-year survival after a stroke.

IScore A Risk Score to Predict Death Early After Hospitalization for an Acute Ischemic Stroke

Background— A predictive model of stroke mortality may be useful for clinicians to improve communication with and care of hospitalized patients. Our aim was to identify predictors of mortality and to develop and validate a risk score model using information available at hospital presentation. Methods and Results— This retrospective study included 12 262 community-based patients presenting with an acute ischemic stroke at multiple hospitals in Ontario, Canada, between 2003 and 2008 who had been identified from the Registry of the Canadian Stroke Network (8223 patients in the derivation cohort, 4039 in the internal validation cohort) and the Ontario Stroke Audit (3720 for the external validation cohort). The mortality rates for the derivation and internal validation cohorts were 12.2% and 12.6%, respectively, at 30 days and 22.5% and 22.9% at 1 year. Multivariable predictors of 30-day and 1-year mortality included older age, male sex, severe stroke, nonlacunar stroke subtype, glucose ≥7.5 mmol/L (135 mg/dL), history of atrial fibrillation, coronary artery disease, congestive heart failure, cancer, dementia, kidney disease on dialysis, and dependency before the stroke. A risk score index stratified the risk of death and identified low- and high- risk individuals. The c statistic was 0.850 for 30-day mortality and 0.823 for 1-year mortality for the derivation cohort, 0.851 for the 30-day model and 0.840 for the 1-year mortality model in the internal validation set, and 0.790 for the 30-day model and 0.782 for the 1-year model in the external validation set. Conclusion— Among patients with ischemic stroke, factors identifiable within hours of hospital presentation predicted mortality risk at 30 days and 1 year. The predictive score may assist clinicians in estimating stroke mortality risk and policymakers in providing a quantitative tool to compare facilities.

Management and outcomes of transient ischemic attacks in Ontario

Background: Canadian data on the characteristics, management and outcomes of patients with transient ischemic attack (TIA) are lacking. We studied prospectively a cohort of consecutive patients presenting with TIA to the emergency department of 4 regional stroke centres in Ontario. Methods: Using data from the Ontario Stroke Registry linked with provincial administrative databases, we determined the short-term outcomes after TIA and assessed patient management in the emergency department and within 30 days after the index TIA. We compared the TIA patients with a cohort of patients who had ischemic stroke. Results: Three-quarters of the TIA patients were discharged from the emergency department. After discharge, the 30-day stroke risk was 5% (13/265) overall and 8% (13/167) among those with a first-ever TIA; the 30-day risk of stroke or death was 9% (11/127) among the TIA patients with a speech deficit and 12% (9/76) among those with a motor deficit. Half of the cases of stroke occurred within the first 2 days after the TIA. Diagnostic investigations were underused in hospital and on an outpatient basis within 30 days after the index TIA, the rates being as follows: CT scanning, 58% (211/364); carotid Doppler ultrasonography, 44% (162/364); echocardiography, 19% (70/364); cerebral angiography, 5% (19/364); and MRI, 3% (11/364). Antithrombotic therapy was not prescribed for more than one-third of the patients at discharge. Carotid endarterectomy was performed in 2% within 90 days. Interpretation: Patients in whom TIA is diagnosed in the emergency department have high immediate and short-term risks of stroke. However, their condition is underinvestigated and undertreated compared with stroke: many do not receive the minimum recommended diagnostic tests within 30 days. We need greater efforts to improve the timely delivery of care for TIA patients, along with investigation of treatments administered early after TIA to prevent stroke.

The effect of English language proficiency on length of stay and in-hospital mortality

AbstractBACKGROUND: In ambulatory care settings, patients with limited English proficiency receive lower quality of care. Limited information is available describing outcomes for inpatients. OBJECTIVE: To investigate the effect of English proficiency on length of stay (LOS) and in-hospital mortality. DESIGN: Retrospective analysis of administrative data at 3 tertiary care teaching hospitals (University Health Network) in Toronto, Canada. PARTICIPANTS: Consecutive inpatient admissions from April 1993 to December 1999 were analyzed for LOS differences first by looking at 23 medical and surgical conditions (59,547 records) and then by a meta-analysis of 220 case mix groups (189,119 records). We performed a similar analysis for in-hospital mortality. MEASUREMENTS: LOS and odds of in-hospital death for limited English-proficient (LEP) patients relative to English-proficient (EP) patients. RESULTS: LEP patients stayed in hospital longer for 7 of 23 conditions (unstable coronary syndromes and chest pain, coronary artery bypass grafting, stroke, craniotomy procedures, diabetes mellitus, major intestinal and rectal procedures, and elective hip replacement), with LOS differences ranging from approximately 0.7 to 4.3 days. A meta-analysis using all admission data demonstrated that LEP patients stayed 6% (approximately 0.5 days) longer overall than EP patients (95% confidence interval, 0.04 to 0.07). LEP patients were not at increased risk of in-hospital death (relative odds, 1.0; 95% confidence interval, 0.9 to 1.1). CONCLUSIONS: Patients with limited English proficiency have longer hospital stays for some medical and surgical conditions. Limited English proficiency does not affect in-hospital mortality. The effect of communication barriers on outcomes of care in the inpatient setting requires further exploration, particularly for selected conditions in which length of stay is significantly prolonged.

Preadmission antithrombotic treatment and stroke severity in patients with atrial fibrillation and acute ischaemic stroke: an observational study

BACKGROUND Vitamin K antagonists (eg, warfarin) substantially reduce the risk of ischaemic stroke in patients with atrial fibrillation. Additionally, therapeutic anticoagulation at time of acute stroke admission might reduce in-hospital mortality and disability. We assessed the association between preadmission antithrombotic treatment and initial stroke severity, neurological deterioration, major vascular events during hospital stay, and death or disability at discharge in patients with acute ischaemic stroke and atrial fibrillation. METHODS We identified consecutive patients with acute ischaemic stroke and atrial fibrillation, admitted to 11 hospitals in Ontario, Canada, from the Registry of the Canadian Stroke Network (2003-05). Logistic regression was used to assess the association between antiplatelet treatment, subtherapeutic warfarin treatment (admission international normalised ratio [INR] < 2), therapeutic warfarin treatment (admission INR > or = 2), and clinical outcome. Stroke severity was measured using the Canadian neurological scale (CNS) and was categorised into mild (CNS > 7) and severe stroke (CNS < or = 7). Disability was measured with the modified-Rankin scale (mRS) and was categorised into strokes associated with no or mild-moderate dependency (mRS 0-3) and with severe dependency or death (mRS 4-6). RESULTS Of 948 patients, 306 (32%) were not on antithrombotic treatment, 292 (31%) were receiving antiplatelet treatment, 238 (25%) were receiving warfarin with a subtherapeutic INR, and 112 (12%) were receiving warfarin with a therapeutic INR on admission. Compared with those not receiving antithrombotic therapy, antiplatelet therapy (odds ratio 0.7; 95% CI 0.5-0.995) and therapeutic warfarin (0.4; 0.2-0.6) were associated with a reduction in severe stroke at admission. Therapeutic warfarin was also associated with a reduction in the odds of severe disability or death at discharge (0.5; 0.3-0.9). INTERPRETATION Therapeutic warfarin is associated with reduced severity of ischaemic stroke at presentation and reduced disability or death at discharge in patients with atrial fibrillation. Antiplatelet treatment is associated with a more modest reduction than warfarin in baseline stroke severity.

Variables Associated With 7-Day, 30-Day, and 1-Year Fatality After Ischemic Stroke

Background and Purpose— Seven-day, 30-day, and 1-year case-fatality indicators have been used to compare stroke care among hospitals, provinces, and countries and to implement quality improvement strategies. However, limited information is available concerning variables associated with stroke case fatality at these different points in time. We sought to identify and compare variables associated with 7-day, 30-day, and 1-year stroke fatality. Methods— This was a cohort study of consecutive patients with acute ischemic stroke admitted to 11 stroke centers in Ontario, Canada, between July 2003 and March 2005 and captured in the Registry of the Canadian Stroke Network (RCSN). The RCSN database was linked to administrative databases to capture all deaths occurring within 7, 30, and 365 days of hospital admission for ischemic stroke. Logistic regression was used to determine variables associated with stroke fatality at each time point. Outcome measures were all-location mortality within 7 days, 30 days, and 1 year of hospital admission. Results— Our cohort included 3631 patients admitted with ischemic stroke. Seven-day case fatality was 6.9% (249/3631), 30-day case fatality was 12.6% (457/3631), and 1-year case fatality was 23.6% (856/3631). In the multivariable analyses, stroke severity, neurologic deterioration during hospitalization, nonuse of antithrombotics during hospital admission, and lack of assessment by a stroke team were the most consistent predictors of case fatality at 7 days, 30 days, and 1 year after stroke. Physician experience in stroke management was inversely associated with 7-day and 30-day mortality, whereas age, comorbid illness, and pneumonia during hospital admission were associated with 30-day and 1-year mortality. Conclusions— Stroke severity and certain processes of care were associated with case fatality at 7days, 30 days, and 1 year after stroke. This information may be useful for comparing risk-adjusted case-fatality rates among hospitals and for implementing strategies to improve the processes and quality of care in the acute phase of stroke.