Incidence and case-fatality rate of stroke in General Villegas, Buenos Aires, Argentina. The EstEPA population study.

OBJECTIVES: Stroke epidemiology varies among different populations. The burden of stroke is high in low- and middle-income countries. Reliable population data is needed to assess the impact of stroke and to develop policies aimed to improve stroke care in our region. EstEPA is a population-based project assessing prevalence, incidence, mortality and burden of stroke in General Villegas Department, Buenos Aires, Argentina (pop=30,864 inhabitants). We determined incidence of stroke (first-ever and recurrent stroke) and stroke case-fatality rate from 2017 to 2020. METHODS: First-ever strokes, recurrent strokes and transient ischemic attacks were ascertained and case-fatality rate was obtained. Diagnoses were based on standard AHA/WHO definitions. Study population included all persons residing in General Villegas during the three-year period. Hospitals, households, nursing homes, death certificates and several overlapping sources were surveyed. RESULTS: We assessed 92,592 person-years. There were 155 cerebrovascular events aged 70 years (SD ± 13 years), of which 115 were first-ever strokes (74%), 21 recurrent strokes (13.5%) and 19 transient ischemic attacks (12.5%). The crude overall incidence rate of first-ever strokes was 124.2 per 100,000 population (86.9 per 100,000 [95% CI 58.5-115.2] when standardized by WHO World population and 109.7 per 100,000 [95% CI 89.7-129.8] when standardized by Argentine population) and 317.0 per 100,000 population in subjects older than 40 years. Case fatality rate at 30 days of first-ever strokes was 27%. CONCLUSION: In this population-based comprehensive stroke epidemiological study in Argentina, first-ever stroke incidence in an urban population was 124.2 per 100,000 population (86.9 per 100,000 adjusted by the WHO World population). This is lower than the incidence in other countries in the region and similar to a recent incidence study in Argentina. It is also comparable to reported incidence in most middle- and high-income countries. Stroke case-fatality rate was comparable to other population-based Latin-American studies.

A Population-Based Survey of Stroke Knowledge in Argentina: The SIFHON Study.

BACKGROUND AND OBJECTIVES: Information about stroke awareness in Latin America is scant. We conducted a large population survey in Argentina to assess stroke knowledge. METHODS: We distributed 110,000 multiple-choice anonymous questionnaires using the house distribution system of a bottled water dispensing company. The survey assessed demographic characteristics and stroke knowledge. RESULTS: A total of 12,710 surveys were returned (12%). Even though 95% of the respondents reported some prior information about stroke, only 37% had adequate knowledge based on prespecified criteria. The Spanish acronym for accidente cerebrovascular, was the most frequently identified name for stroke. Sixty nine percent of respondents were able to identify stroke main risk factors and only 29% knew about transient ischemic attacks. If a hypothetical scenario of stroke was presented, 63% knew the existence of a time-dependent treatment, 25% would call an ambulance, and 50% would go to an emergency room by own means. A lower degree of knowledge was present in young, single, and nonuniversity men. CONCLUSIONS: This study represents the largest stroke awareness survey in a Spanish-speaking population. There was good recognition of some basic facts of stroke. However, the population had poor knowledge of prevalence and severity of the disease, transient ischemic attacks, and treatment availability.

Stroke Epidemiology in Argentina. Design of a Population-Based Study in General Villegas (EstEPA).

BACKGROUND: Epidemiological data on stroke is scarce in Latin America. Estudio Epidemiológico Poblacional sobre Accidente Cerebrovascular (EstEPA) is a population-based program planned to assess prevalence, incidence, mortality, and burden of disease for stroke in the Department of General Villegas, province of Buenos Aires, Argentina. METHODS AND DESIGN: Prevalence study will consist of a two-phase survey approach in the urban area of General Villegas. First, trained social workers with a structured questionnaire will collect data in 2000 randomly selected housing units. Those subjects screened positive for possible strokes will be interviewed and examined by stroke neurologists to confirm diagnosis. The incidence study will be performed according to the methodology of WHO STEPS stroke surveillance manual and will detect all new strokes in the department during a 5-year period. General and disease-specific mortality rates will be assessed monthly during a 5-year period, using different sources of information. To assess the overall burden of cerebrovascular disease, disability adjusted life years will be calculated. DISCUSSION: EstEPA will assess for the first time all aspects of stroke epidemiology in Argentina. Its results will help to implement population-based interventions and to properly allocate public health resources.

Ischemic stroke in patients with atrial fibrillation receiving oral anticoagulation.

BACKGROUND: Atrial fibrillation is the most common cause of embolic stroke associated to heart disease. Oral anticoagulation with vitamin K antagonists substantially reduces this risk. AIMS: We assessed a group of patients with prior diagnosis of atrial fibrillation who sustained an ischemic stroke while receiving an adequate regime of oral anticoagulation. METHODS: We evaluated consecutive patients with ischemic stroke and prior diagnosis of atrial fibrillation. We determined demographics, clinical characteristics, TOAST stroke subtypes, CHADS2 scores, and prior or concomitant use of oral anticoagulants. RESULTS: We studied 112 patients. Thirty nine of them (35%) had received an adequate dose of a vitamin K antagonist during the 24-hour period preceding the stroke. There were no differences in demographics, vascular risk factors, CHADS2 scores, nor medications use between patients who were or were not receiving anticoagulation. Other potential etiologies for stroke occurrence were found in 8 (21%) anticoagulated patients, and in 3 (4%) non-anticoagulated subjects (p<0.01). Anticoagulated patients had a mean international normalized ratio (INR) of 2.3 ± 1.3 (median 2.05), and INR was within therapeutic ranges (i.e., ≥ 2) in 54% of these subjects. CONCLUSIONS: A substantial proportion of patients with atrial fibrillation who have an ischemic stroke are already receiving oral anticoagulation. Sub-optimal levels of anticoagulation and additional etiologies explain, only in part, this failure. Further research is needed to help find adequate therapeutic strategies in atrial fibrillation patients who sustain an ischemic stroke while receiving oral anticoagulation.

Ischemic stroke in patients receiving aspirin.

BACKGROUND: The widespread use of aspirin-driven vascular prevention strategies does not impede the occurrence of first and recurrent ischemic strokes in numerous subjects. It is not clear what factors are associated with aspirin failure beyond the functional diagnosis of aspirin resistance in selected subjects. Current management guidelines provide little or no recommendations on the proper strategy for subjects who had a stroke while receiving aspirin. We assessed clinical features of subjects who had a first or recurrent stroke while taking aspirin. METHODS: We studied demographic characteristics, vascular risk factors, stroke subtypes, and concomitant medication use in subjects with first or recurrent ischemic strokes. Patients receiving antiplatelet medications other than aspirin and/or oral anticoagulants were excluded from this analysis. RESULTS: Seven hundred and nine patients with first (n = 552) or recurrent (n = 157) ischemic stroke were evaluated. Aspirin was being taken by 29% of first and 48% of recurrent stroke subjects. There was a higher prevalence of hypertension, hypercholesterolemia, and smoking in aspirin users with first and recurrent stroke (P < .05). Diabetes and coronary artery disease were more frequent in aspirin users with first ischemic strokes (P < .003), but not in those who had recurrent ischemic strokes. Aspirin users were more likely to be also receiving statins and antihypertensive drugs (P < .001). CONCLUSIONS: Aspirin failure in ischemic stroke prevention may exceed functional resistance to aspirin and could be associated with a higher prevalence of lacunar stroke, comorbidities, and/or adverse interactions with other drugs. These patients may require a different approach regarding prevention strategies.

[Morbidity and mortality of carotid endarterectomy]. / Morbi-mortalidad de la endarterectomía carotídea.

Clinical trials in academic centers with high selected surgeons have demonstrated the effectiveness of carotid endarterectomy (CE) in addition to best medical treatment in symptomatic and asymptomatic patients with moderate to severe stenosis. International guidelines recommend that the procedure should be done in centers with morbidity and mortality rates of less than 6% for symptomatic and 3% for asymptomatic patients. We evaluated the morbidity and mortality of CE in our institution. This was defined by the presence of stroke, myocardial infarction and/or death within 30 days of surgery. Surgery was indicated in symptomatic patients with stenosis greater than 50%. For asymptomatic or symptomatic patients with stenosis = 50% treatment was decided on a case-by-case basis. All patients were examined by a neurologist with and a cardiologist before and after the procedure. Intraoperative monitoring with transcranial Doppler was routinely used in patients with adequate ultrasonic window. We evaluated 306 procedures. No deaths occurred. Perioperative morbidity was 2.6% for both, symptomatic and asymptomatic subjects. These numbers compared favorably with those reported by other centers in Latin America and Europe. In conclusion, CE can be performed in routine clinical practice with morbidity and mortality results within those recommended by international guidelines.

Morbi-mortalidad de la endarterectomía carotídea / Morbidity and mortality of carotid endarterectomy

La endarterectomía carotídea (EC) en adición al mejor tratamiento médico mostró reducción del riesgo de eventos cerebrovasculares en pacientes sintomáticos y asintomáticos con estenosis moderada-grave del vaso en ensayos clínicos en centros académicos con cirujanos altamente seleccionados. Las principales guías internacionales recomiendan que el procedimiento se realice en centros con morbi-mortalidad auditada menor al 6% para pacientes sintomáticos y 3% para asintomáticos. Evaluamos la morbi-mortalidad peri-procedimiento en nuestro centro. Esta fue definida como la presencia de accidente cerebrovascular, infarto de miocardio y/o muerte dentro de los 30 días de la cirugía. Se indicó el procedimiento en pacientes sintomáticos con estenosis > 50%. En pacientes asintomáticos o sintomáticos con estenosis ≤ 50% se decidió el tratamiento sobre una base caso por caso. Todos los pacientes fueron examinados por un neurólogo y un cardiólogo antes y después de la EC. Se utilizó en forma rutinaria monitoreo intraoperatorio con Doppler transcraneano en los pacientes con adecuada ventana ultrasónica. Se evaluaron 306 endarterectomías carotídeas. No se registraron muertes. La morbilidad perioperatoria fue de 2.6% tanto para individuos sintomáticos como asintomáticos. Estos índices se compararon favorablemente con informes de otros centros de Latinoamérica y Europa. En conclusión, este informe muestra que la EC puede realizarse en la práctica clínica cotidiana con morbi-mortalidad peri-procedimiento dentro de los niveles recomendados por las guías internacionales.

Clinical trials in academic centers with high selected surgeons have demonstrated the effectiveness of carotid endarterectomy (CE) in addition to best medical treatment in symptomatic and asymptomatic patients with moderate to severe stenosis. International guidelines recommend that the procedure should be done in centers with morbidity and mortality rates of less than 6% for symptomatic and 3% for asymptomatic patients. We evaluated the morbidity and mortality of CE in our institution. This was defined by the presence of stroke, myocardial infarction and/or death within 30 days of surgery. Surgery was indicated in symptomatic patients with stenosis greater than 50%. For asymptomatic or symptomatic patients with stenosis ≤ 50% treatment was decided on a case-by-case basis. All patients were examined by a neurologist with and a cardiologist before and after the procedure. Intraoperative monitoring with transcranial Doppler was routinely used in patients with adequate ultrasonic window. We evaluated 306 procedures. No deaths occurred. Perioperative morbidity was 2.6% for both, symptomatic and asymptomatic subjects. These numbers compared favorably with those reported by other centers in Latin America and Europe. In conclusion, CE can be performed in routine clinical practice with morbidity and mortality results within those recommended by international guidelines.