Sex Differences in Outcomes after Stroke in Patients with Diabetes in Ontario, Canada.

BACKGROUND: Outcomes after stroke in those with diabetes are not well characterized, especially by sex and age. We sought to calculate the sex- and age-specific risk of cardiovascular outcomes after ischemic stroke among those with diabetes. METHODS: Using population-based demographic and administrative health-care databases in Ontario, Canada, all patients with diabetes hospitalized with index ischemic stroke between April 1, 2002, and March 31, 2012, were followed for death, stroke, and myocardial infarction (MI). The Kaplan-Meier survival analysis and Fine-Gray competing risk models estimated hazards of outcomes by sex and age, unadjusted and adjusted for demographics and vascular risk factors. RESULTS: Among 25,495 diabetic patients with index ischemic stroke, the incidence of death was higher in women than in men (14.08 per 100 person-years [95% confidence interval [CI], 13.73-14.44] versus 11.89 [11.60-12.19]) but was lower after adjustment for age and other risk factors (adjusted hazard ratio [HR], .95 [.92-.99]). Recurrent stroke incidence was similar by sex, but men were more likely to be readmitted for MI (1.99 per 100 person-years [1.89-2.10] versus 1.58 [1.49-1.68] among females). In multivariable models, females had a lower risk of readmission for any event (HR, .96 [95% CI, .93-.99]). CONCLUSIONS: In this large, population-based, retrospective study among diabetic patients with index stroke, women had a higher unadjusted death rate but lower unadjusted incidence of MI. In adjusted models, females had a lower death rate compared with males, although the increased risk of MI among males persisted. These findings confirm and quantify sex differences in outcomes after stroke in patients with diabetes.

Sex Differences in the Presentation, Care, and Outcomes of Transient Ischemic Attack: Results From the Ontario Stroke Registry.

BACKGROUND AND PURPOSE: Little is known about whether sex differences exist in the presentation, management, and outcomes of transient ischemic attack. METHODS: We conducted a cohort study of 5991 consecutive patients with transient ischemic attack admitted to 11 stroke centers in Ontario, Canada, between July 1, 2003, and March 31, 2008 and compared presenting symptoms, processes of care, and outcomes in women and men. We used linkages to administrative databases to evaluate mortality and recurrent vascular events within 30 days and 1 year of the initial presentation, with multivariable analyses to assess whether sex differences persisted after adjustment for age and comorbid conditions. RESULTS: The most common presenting symptoms for both sexes were weakness, speech impairment, and sensory deficit, with headache being slightly more frequent in women. Women were less likely than men to undergo carotid imaging, carotid endarterectomy, or receive lipid-lowering therapy. One-year mortality was slightly lower in women than in men (adjusted hazard ratio, 0.77; 95% confidence interval, 0.63-0.94). CONCLUSIONS: We found only minor sex differences in the presentation and management of transient ischemic attack, suggesting that current public awareness campaigns focusing on classic warning signs are appropriate for both women and men. Future work should focus on evaluating whether lower rates of carotid imaging, endarterectomy, and lipid-lowering therapy in women reflect undertreatment of women or are appropriate based on patient eligibility.

Low Use of Oral Anticoagulant Prescribing for Secondary Stroke Prevention: Results From the Ontario Stroke Registry.

BACKGROUND: Oral anticoagulation reduces the risk of stroke in atrial fibrillation but is often underused. OBJECTIVES: To identify factors associated with oral anticoagulant prescribing and adherence after stroke or transient ischemic attack (TIA). RESEARCH DESIGN: Retrospective cohort study using linked Ontario Stroke Registry and prescription claims data. SUBJECTS: Consecutive patients with atrial fibrillation and ischemic stroke/TIA admitted to 11 stroke centers in Ontario, Canada between 2003 and 2011. MEASURES: We used modified Poisson regression models to determine predictors of anticoagulant prescribing and multiple logistic regression to determine predictors of 1-year adherence. RESULTS: Of the 5781 patients in the study cohort, 4235 (73%) were prescribed oral anticoagulants at discharge. Older patients were less likely to receive anticoagulation [adjusted relative risk (aRR) for each additional year=0.997; 95% confidence interval (CI), 0.995-0.998], as were those with TIA compared with ischemic stroke (aRR=0.904; 95% CI, 0.865-0.945), prior gastrointestinal bleed (aRR=0.778; 95% CI, 0.693-0.873), dementia (aRR=0.912; 95% CI, 0.856-0.973), and those from a long-term care facility (aRR=0.810; 95% CI, 0.737-0.891). After limiting the sample to those without obvious contraindications to anticoagulation, age, dementia, and long-term care residence continued to be associated with lower prescription of oral anticoagulants. One-year adherence to therapy was similar across most patient groups. CONCLUSIONS: Age, dementia, and long-term care residence are predictors of lower oral anticoagulant use for secondary stroke prevention and represent key target areas for quality improvement initiatives.

Temporal Trends in the Use of Investigations After Stroke or Transient Ischemic Attack.

BACKGROUND: Guidelines recommend that patients with stroke or transient ischemic attack (TIA) undergo neuroimaging and cardiac investigations to determine etiology and guide treatment. It is not known how the use of these investigations has changed over time and whether there have been associated changes in management. OBJECTIVES: To evaluate temporal trends in the use of brain and vascular imaging, echocardiography, and antithrombotic and surgical therapy after stroke or TIA. RESEARCH DESIGN: We analyzed 42,738 patients with stroke or TIA presenting to any of the 11 regional stroke centers in Ontario, Canada between 2003 and 2012 using the Ontario Stroke Registry database. The study period was divided into 1-year intervals and we used the Cochran-Armitage test to determine trends over time. RESULTS: Between 2003/2004 and 2011/2012, the proportion of patients undergoing brain imaging increased from 96% to 99%, as did the proportion receiving ≥3 brain scans (21%-39%), magnetic resonance imaging (13%-50%), vascular imaging (62%-88%), or echocardiography (52%-70%) (P<0.0001 for all comparisons). There was an increase in the proportion receiving any antithrombotic therapy (83%-91%, P<0.0001) but no change in use of anticoagulation (25% overall and 68% in subgroup with atrial fibrillation) or carotid revascularization (1.4%-1.5%, P=0.49). CONCLUSIONS: The use of investigations after stroke has increased over time without concomitant changes in medical or surgical management. Although initial neurovascular imaging is in accordance with practice guidelines, the use of multiple imaging procedures and routine echocardiography are of uncertain clinical effectiveness.

Predictors of Hospitalization in Patients With Transient Ischemic Attack or Minor Ischemic Stroke.

BACKGROUND: Transient ischemic attack (TIA) and minor stroke are associated with a substantial risk of subsequent stroke; however, there is uncertainty about whether such patients require admission to hospital for their initial management. We used data from a clinical stroke registry to determine the frequency and predictors of hospitalization for TIA or minor stroke across the province of Ontario, Canada. METHODS: The Ontario Stroke Registry collects information on a population-based sample of all patients seen in the emergency department with acute stroke or TIA in Ontario. We identified patients with minor ischemic stroke or TIA included in the registry between April 1, 2008, and March 31, 2011, and used multivariable analyses to evaluate predictors of hospitalization. RESULTS: Our study sample included 8540 patients with minor ischemic stroke or TIA, 47.2% of whom were admitted to hospital, with a range of 37.6% to 70.3% across Ontario's 14 local health integration network regions. Key predictors of admission were preadmission disability, vascular risk factors, presentation with weakness, speech disturbance or prolonged/persistent symptoms, arrival by ambulance, and presentation on a weekend or during periods of emergency department overcrowding. CONCLUSIONS: More than one-half of patients with minor stroke or TIA were not admitted to the hospital, and there were wide regional variations in admission patterns. Additional work is needed to provide guidance to health care workers around when to admit such patients and to determine whether discharged patients are receiving appropriate follow-up care.

Impact of living alone on the care and outcomes of patients with acute stroke.

BACKGROUND AND PURPOSE: Outcomes among patients living alone at stroke onset could be directly affected by reduced access to acute therapies or indirectly through the effects of social isolation. We examined the associations between living alone at home and acute stroke care and outcomes in the Registry of the Canadian Stroke Network. METHODS: Between 2003 and 2008, 10 048 patients with acute stroke (87% ischemic, 13% hemorrhagic) who were living at home were admitted to 11 Ontario hospitals. Outcomes included arrival≤2.5 hours of onset, thrombolytic treatment, discharge home, 30-day and 1-year mortality, and 1-year readmission. The effects of living alone versus living with others were determined using multivariable logistic regression. RESULTS: Overall, 22.8% (n=2288) of patients were living alone at home before stroke. Subjects living alone were significantly older (mean, 74.6 versus 71.5 years), more likely to be women (61.5% versus 41.4%), widowed (53.7% versus 12.3%), or single (21.5% versus 3.8%). Patients living alone were less likely to arrive within 2.5 hours (28.3% versus 40.0%; adjusted odds ratio, 0.54; 95% confidence interval, 0.48-0.60), to receive thrombolysis (8.0% versus 14.0%; adjusted odds ratio, 0.52; 95% confidence interval, 0.43-0.63), or to be discharged home (46.0% versus 54.7%; adjusted odds ratio, 0.65; 95% confidence interval, 0.58-0.73). There were no significant associations between living alone and mortality or readmission. CONCLUSIONS: Patients living alone had delayed hospital arrival, less thrombolytic therapy, and were less likely to return home. Greater understanding of the inter-relationships among living alone, social isolation, access to stroke care, and outcomes is needed.

Effect of a provincial system of stroke care delivery on stroke care and outcomes.

BACKGROUND: Systems of stroke care delivery have been promoted as a means of improving the quality of stroke care, but little is known about their effectiveness. We assessed the effect of the Ontario Stroke System, a province-wide strategy of regionalized stroke care delivery, on stroke care and outcomes in Ontario, Canada. METHODS: We used population-based provincial administrative databases to identify all emergency department visits and hospital admissions for acute stroke and transient ischemic attack from Jan. 1, 2001, to Dec. 31, 2010. Using piecewise regression analyses, we assessed the effect of the full implementation of the Ontario Stroke System in 2005 on the proportion of patients who received care at stroke centres, and on rates of discharge to long-term care facilities and 30-day mortality after stroke. RESULTS: We included 243 287 visits by patients with acute stroke or transient ischemic attack. The full implementation of the Ontario Stroke System in 2005 was associated with an increase in rates of care at stroke centres (before implementation: 40.0%; after implementation: 46.5%), decreased rates of discharge to long-term care facilities (before implementation: 16.9%; after implementation: 14.8%) and decreased 30-day mortality for hemorrhagic (before implementation: 38.3%; after implementation: 34.4%) and ischemic stroke (before implementation: 16.3%; after implementation: 15.7%). The system's implementation was also associated with marked increases in the proportion of patients who received neuroimaging, thrombolytic therapy, care in a stroke unit and antithrombotic therapy. INTERPRETATION: The implementation of an organized system of stroke care delivery was associated with improved processes of care and outcomes after stroke.

Higher incidence of in-hospital complications in patients with clipped versus coiled ruptured intracranial aneurysms.

BACKGROUND AND PURPOSE: After aneurysmal subarachnoid hemorrhage (SAH), patients with clipped aneurysms have a higher incidence of neurocognitive deficits and seizures compared with patients with coiled aneurysms. It remains unknown if patients with clipped aneurysms also have a higher incidence of other in-hospital complications. METHODS: We used data from the Registry of the Canadian Stroke Network on consecutive patients admitted to hospital with aneurysmal SAH. Patients who died within 2 days after admission were excluded. Baseline characteristics, incidence of various in-hospital complications within 30 days after admission, length of stay, poor functional outcome (modified Rankin Scale score at discharge of ≥3), and mortality were compared between patients with clipped versus coiled aneurysms. RESULTS: Of the 931 patients, 548 (59%) were clipped and 383 (41%) coiled. Baseline characteristics were similar. Compared with patients with coiled aneurysms, patients with clipped aneurysms had a higher incidence of in-hospital complications (37.2% versus 24.5% of patients; P<0.0001), poor functional outcome at discharge (69.4% versus 51.4%; P<0.0001), mortality (at discharge: 14.6% versus 9.1%; P=0.01), and a longer length of stay (17 [interquartile range, 11 to 29] versus 13 [interquartile range, 7 to 22] days; P<0.0001). Higher incidences were observed for urinary tract infection (P=0.02), pneumonia (P=0.01), cardiac/respiratory arrest (P=0.007), seizure (P=0.01), and decubitus ulcer (P=0.02). Urinary tract infection, pneumonia, cardiac/respiratory arrest, and seizure were independent predictors of poor functional outcome. CONCLUSIONS: Patients with clipped aneurysms have a higher incidence of in-hospital complications than patients with coiled aneurysms, which attributes to a higher risk of poor functional outcome and death and an increased length of stay.

Subtherapeutic warfarin is not associated with increased hemorrhage rates in ischemic strokes treated with tissue plasminogen activator.

BACKGROUND AND PURPOSE: Concern exists that preadmission warfarin use may be associated with an increased risk of intracerebral hemorrhage in patients with ischemic stroke receiving intravenous tissue plasminogen activator, even in those with an international normalized ratio <1.7. However, evidence to date has been derived from a small single-center cohort of patients. METHODS: We used data from Phase 3 of the Registry of the Canadian Stroke Network. We compared the rates of post-tissue plasminogen activator hemorrhage, including any intracerebral hemorrhage, symptomatic intracerebral hemorrhage, and gastrointestinal hemorrhage in patients with and without preadmission warfarin use. For those receiving warfarin, we restricted the analysis to patients with an international normalized ratio <1.7 on presentation. Secondary outcomes included functional status and mortality. Multivariate analyses were performed to adjust for other prognostic factors. RESULTS: Our cohort included 1739 patients with acute ischemic stroke treated with intravenous tissue plasminogen activator of whom 125 (7.2%) were receiving warfarin before admission and had an international normalized ratio <1.7. Preadmission warfarin use was not associated with any secondary intracerebral hemorrhage (OR, 1.2; 95% CI, 0.7 to 2.2), symptomatic intracerebral hemorrhage (OR, 1.1; 95% CI, 0.5 to 2.3), or gastrointestinal hemorrhage (OR, 1.1; 95% CI, 0.2 to 5.6). Multivariate analysis showed that preadmission warfarin use was independently associated with a reduced risk of poor functional outcome (OR, 0.6; 95 CI, 0.3 to 0.9), but not with in-hospital mortality (OR, 0.6; 95% CI, 0.3 to 1.0). CONCLUSIONS: The results from the present study suggest that tissue plasminogen activator treatment appears to be safe in patients with acute ischemic stroke taking warfarin with an international normalized ratio <1.7 and may reduce the risk of poor functional outcome.

The Registry of Canadian Stroke Network : an evolving methodology.

Stroke registries can provide information on evidence-based practices and interventions, which are critical for us to understand how stroke care is delivered and how outcomes are achieved. The Registry of Canadian Stroke Network (RCSN) was initiated in 2001 and has evolved over the past decade. In the first two years, we found it extremely difficult to obtain informed consent from the patient or surrogate which led to selection biases in the registry. Subsequently (2003 onwards), under the new health privacy legislation in Ontario, Canada, the RCSN was granted special status as a "prescribed registry" which allowed us to collect data on all consecutive patients at the regional stroke centres without consent. The stroke data was encrypted and all personal contact information had been removed, therefore we could no longer conduct follow- up interviews. To obtain patient outcomes after discharge, we linked the non-consent-based registry database to population-based administrative databases to obtain information on patient mortality, readmissions, socioeconomic status, medication use and other clinical information of interest. In addition, the registry methodology was modified to include a periodic population-based audit on a sample of all stroke patients from over 150 acute hospitals across the province, in addition to continuous data collection at the 12 registry hospitals in the province. The changes in the data collection methodology developed by the RCSN can be applied to other provinces and countries.

Risk of fractures after stroke: Results from the Ontario Stroke Registry.

OBJECTIVE: To determine the risk of fractures after stroke. METHODS: Using the Ontario Stroke Registry, we identified a population-based sample of consecutive patients seen in the emergency department or hospitalized with stroke (n = 23,751) or TIA (n = 11,240) at any of 11 stroke centers in Ontario, Canada, and discharged alive between July 1, 2003, and March 31, 2012. We compared the risk of low-trauma fractures in patients with stroke vs those with TIA using propensity score methods to adjust for differences in baseline factors. Secondary analyses compared fracture risk poststroke with that in age-/sex-matched controls without stroke or TIA (n = 23,751) identified from the Ontario Registered Persons Database. RESULTS: The 2-year rate of fracture was 5.7% in those with stroke compared to 4.8% in those with TIA (adjusted cause-specific hazard ratio [aHR] for those with stroke vs TIA 1.32; 95% confidence interval [CI] 1.19-1.46) and 4.1% in age-/sex-matched controls (aHR for those with stroke vs controls 1.47; 95% CI 1.35-1.60). In the cohort with stroke, factors associated with fractures were older age, female sex, moderate stroke severity, prior fractures or falls, and preexisting osteoporosis, rheumatoid arthritis, hyperparathyroidism, and atrial fibrillation. CONCLUSIONS: Stroke is associated with an increased risk of low-trauma fractures. Individuals with stroke and additional risk factors for fractures may benefit from targeted screening for low bone mineral density and initiation of treatment for fracture prevention.

Stroke recurrence among South Asians with diabetes in Ontario, Canada.

Background South Asians have more vascular risk factors, earlier cardiovascular disease onset, and higher stroke mortality than non-South Asians. However, ethnic differences in long-term outcomes post-stroke in diabetics are unclear. Aims We compared cardiovascular outcome risk after first ischemic stroke between South Asian and non-South Asian diabetics. Methods Using population-based health care databases in Ontario, Canada, we selected all patients with diabetes hospitalized with first ischemic stroke between 1 April 2002 and 31 March 2012, and assigned South Asian versus non-South Asian ethnicity using a validated surname algorithm. Kaplan-Meier survival analysis estimated survival functions, and competing risk models estimated hazards of death, stroke, and myocardial infarction. The primary predictor was ethnicity, and models were adjusted for demographics and vascular risk factors. Sensitivity analysis including adjustment for medication use was performed in those aged ≥65 years. Results There were 25,495 diabetics with first ischemic stroke; 840 were South Asian. South Asians were younger, more often male, had lower income, and had shorter Ontario residency compared to non-South Asians. South Asians had higher incidence and cumulative risk of recurrent stroke. In fully adjusted competing risk models, recurrent stroke rate was increased among South Asians compared to non-South Asians (HR 1.17 [95% CI 1.00-1.38]) in the whole cohort and in those aged ≥65 years, both with adjustment for medication use (HR 1.23 [1.01-1.50]) and without (1.27 [1.04-1.54]). Conclusions In this large population-based study, South Asian diabetic stroke patients had higher recurrent stroke rates compared to non-South Asians, despite a younger age profile. Further research is needed to reduce stroke burden in South Asians.

The association between rural residence and stroke care and outcomes.

BACKGROUND: Little is known about stroke care and outcomes in those residing in rural compared to urban areas. METHODS: We conducted a cohort study on a population-based sample of patients with stroke or transient ischemic attack seen at 153 acute care hospitals in the province of Ontario, Canada, between April 1, 2008 and March 31, 2011. Based on their primary residence, patients were categorized as residing in a rural (population<10,000), medium urban (population 10,000-99,999) or large urban (population≥100,000) area. In the study sample of 15,713, we compared processes of stroke care (use of thrombolysis, stroke unit care, investigations, consultations and treatments) and outcomes (30-day mortality, disability at discharge) in those from rural and urban areas, with multivariable models constructed to evaluate the association between rural residence and outcomes after adjustment for potential confounders. RESULTS: Patients from rural areas were less likely than those from urban areas to receive stroke unit care, brain imaging within 24 h, carotid imaging, and consultations from neurologists, physiotherapists, occupational therapists and speech language pathologists, and were less likely to be transferred to inpatient rehabilitation facilities. Use of antithrombotic agents and lipid lowering therapy was similar in rural and urban residents, as was disability at discharge. There was a trend toward higher 30-day mortality in rural compared to urban residents (adjusted hazard ratio 1.14; 95% confidence interval 0.99-1.32). CONCLUSION: Rural residence is associated with lower use of key stroke care interventions after stroke. Future work should focus on developing interventions to address gaps in stroke care in rural areas.

Association between hospitalization and care after transient ischemic attack or minor stroke.

OBJECTIVE: To evaluate the care and outcomes of patients with TIA or minor stroke admitted to the hospital vs discharged from the emergency department (ED). METHODS: We used the Ontario Stroke Registry to create a cohort of patients with minor ischemic stroke/TIA who presented to the hospital April 1, 2008, to March 31, 2009, or April 1, 2010, to March 31, 2011, in the province of Ontario, Canada. We compared processes of care and outcomes (death or recurrent stroke/TIA) in patients admitted to the hospital and discharged with and without stroke prevention clinic follow-up. RESULTS: In our sample of 8,540 patients, the use of recommended interventions was highest in admitted patients, followed by discharged patients referred to prevention clinics, followed by those discharged without clinic referral. Eight percent of nonadmitted patients returned to the hospital with recurrent stroke/TIA within 1 week of the index event. One-year stroke case-fatality was similar in admitted and discharged patients (adjusted hazard ratio 1.11; 95% confidence interval 0.92-1.34). Among patients discharged from EDs, referral to a stroke prevention clinic was associated with a markedly lower risk of mortality (adjusted hazard ratio 0.49; 95% confidence interval 0.38-0.64). CONCLUSIONS: Patients with minor ischemic stroke or TIA discharged from the ED are less likely than admitted patients to receive timely stroke care interventions. Among discharged patients, referral to a stroke prevention clinic is associated with improved processes of care and lower mortality. Additional strategies are needed to improve access to high-quality outpatient TIA care.

Care and Outcomes of Patients With In-Hospital Stroke.

IMPORTANCE: A sizeable minority of strokes occur in hospitalized patients. However, little is known about the presentation, care, and outcomes of stroke in this subgroup of patients. OBJECTIVE: To examine stroke care delivery and outcomes for patients with in-hospital vs community-onset stroke. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study of all patients older than 18 years with acute stroke seen in the emergency department or admitted to the hospital at participating centers (all regional stroke centers in Ontario, Canada) between July 1, 2003, and March 31, 2012, including those with stroke onset during hospitalization for another cause. MAIN OUTCOMES AND MEASURES: We compared processes of stroke care delivery, including time to neuroimaging and rates of thrombolysis, as well as outcomes, including death and disability, in those with in-hospital vs community-onset stroke. We used multiple logistic regression models to adjust for age, sex, comorbid conditions, and stroke type and severity. RESULTS: The study sample included 973 patients with in-hospital stroke and 28 837 with community-onset stroke. Patients with in-hospital stroke compared with those with community-onset stroke had significantly longer waiting times from symptom recognition to neuroimaging (median, 4.5 vs 1.2 hours; P < .001; for <2 hours, 32% vs 63%; adjusted odds ratio [AOR] = 0.21; 95% CI, 0.18-0.24), lower use of thrombolysis (12% vs 19% of those with ischemic stroke; AOR = 0.54; 95% CI, 0.43-0.67; P < .001), and longer time from stroke recognition to administration of thrombolysis (median, 2.0 vs 1.2 hours; P < .001). After adjustment for age, stroke severity, and other factors, mortality rates at 30 days and 1 year after stroke were similar in those with in-hospital stroke and community-onset stroke; however, those with in-hospital stroke had a longer median length of stay following stroke onset (17 vs 8 days; P < .001), were more likely to be dead or disabled at discharge (77% vs 65% with modified Rankin Scale score of 3-6; AOR = 1.64; 95% CI, 1.38-1.96; P < .001), and were less likely to be discharged home from the hospital (35% vs 44%; AOR = 0.76; 95% CI, 0.64-0.90; P < .001). CONCLUSIONS AND RELEVANCE: Compared with those with community-onset stroke, patients with in-hospital stroke had delays in investigations and treatment, suggesting a need for a standardized approach to the recognition and management of in-hospital stroke, with the aim of ensuring access to rapid acute stroke care.