Rodrigo Salinas

Stroke epidemiology, prevention, and management strategies at a regional level: Latin America and the Caribbean

Stroke is a major health problem in Latin American and Caribbean countries. In this paper, we review the epidemiology, aetiology, and management of stroke in the region based on a systematic search of articles published in Spanish, Portuguese, and English. Stroke mortality is higher than in developed countries but rates are declining. Population-based studies show variations in incidence of strokes: lower rates of ischaemic stroke and similar rates of intracranial haemorrhages, compared with other regions. A significant proportion of strokes in these populations can be attributed to a few preventable risk factors. Some countries have published national clinical guidelines, although much needs to be done in the organisation of care and rehabilitation. Even though the burden of stroke is high, there is a paucity of information for implementing evidence-based management. The Global Stroke Initiative, the WHO STEPS Stroke surveillance, and WHO-PREMISE projects provide opportunities for surveillance at institutional and community levels.

Incidence, case-fatality rate, and prognosis of ischaemic stroke subtypes in a predominantly Hispanic-Mestizo population in Iquique, Chile (PISCIS project): a community-based incidence study

BACKGROUND Incidence of ischaemic stroke subtypes, classified by cause, seems to vary between communities. We aimed to prospectively ascertain the incidence of first-ever ischaemic stroke in a predominantly Hispanic-Mestizo population in the northern desertic region of Chile. METHODS Between July, 2000, and June, 2002, all patients with possible stroke or transient ischaemic attacks were identified from multiple overlapping sources and were rapidly assessed by two field neurologists. All identified patients were diagnosed by at least two stroke neurologists according to Trial of Org 10172 in Acute Stroke Treatment (TOAST) definitions and were followed up at 6 months. Annual incidence rates were age adjusted to WHO, European, and US populations by the direct method to allow comparisons. FINDINGS A total of 239 ischaemic strokes were identified, of which 185 (77%) were first-ever cases. 151 (82%) patients were hospitalised, of whom only 70 (38%) were assessed within 6 h of symptom onset. The mean age of patients was 66.4 years (SD 14.9) and 56% were men. The crude annual incidence rates (per 100 000) according to stroke subtype were: cardioembolic, 9.3; large-artery disease, 2.0; small-vessel disease, 15.8; other determined cause, 0.2; and undetermined cause, 17.4. Hypertension was the most common cardiovascular risk factor in all subtypes and atrial fibrillation was the most common cause of cardioembolic stroke. Case fatality at 30 days was highest in cardioembolic strokes (28%) and lowest in small-vessel disease (0%). Dependency or death at 6 months was also highest in cardioembolic strokes (62%) and lowest in small-vessel disease (21%). INTERPRETATION Incidence and prognosis of small vessel and cardioembolic infarction was similar to that in other populations and incidence of large-artery atherothrombotic infarction was lower than in most previous reports. Hypertension and atrial fibrillation were the most common risk factor and cause, respectively, of ischemic stroke in this population. These findings should help the national stroke programme in the prevention of cardioembolic stroke, increase access to specialists and acute brain imaging and vascular studies, and improve stroke care.

Incidence of Lobar and Non-Lobar Spontaneous Intracerebral Haemorrhage in a Predominantly Hispanic-Mestizo Population – The PISCIS Stroke Project: A Community-Based Prospective Study in Iquique, Chile

Background: The incidence of intracerebral haemorrhage (ICH) in Hispanics is high, especially of non-lobar ICH. Our aim was to ascertain prospectively the incidence of first-ever spontaneous ICH (SICH) stratified by localisation in a Hispanic-Mestizo population of the north of Chile. Methods: Between July 2000 and June 2002 all possible cases of ICH were ascertained from multiple overlapping sources. The cases were allocated according to localisation. Those with vascular malformations or non-identifiable localisations were excluded. Results: We identified a total of 69 cases of first-ever ICH. Of these, 64 (92.7%) had SICH, of which we allocated 58 cases (84%) to non-lobar or lobar localisation. The mean age was 57.3 ± 17 years, and 62.3% of the subjects were male. The age-adjusted incidence rates were 13.8 (non-lobar) and 4.9 (lobar) per 100,000 person-years. Non-lobar SICH was more frequent in young males and lobar SICH in older women. The non-lobar-to-lobar ratio was similar to previous findings in Hispanics. Hypertension was more frequent in non-lobar SICH and in diabetes, heavy drinking and antithrombotic use in lobar SICH, but in none significantly. There was no association between localisation and prognosis. Conclusions: The incidence of non-lobar SICH was high, but lower than in most non-white populations. This lower incidence could be due to a lower population prevalence of risk factors, a higher socioeconomic level in this population, or chance.

A comparative analysis of biomedical research ethics regulation systems in Europe and Latin America with regard to the protection of human subjects

The European project European and Latin American Systems of Ethics Regulation of Biomedical Research Project (EULABOR) has carried out the first comparative analysis of ethics regulation systems for biomedical research in seven countries in Europe and Latin America, evaluating their roles in the protection of human subjects. We developed a conceptual and methodological framework defining ‘ethics regulation system for biomedical research’ as a set of actors, institutions, codes and laws involved in overseeing the ethics of biomedical research on humans. This framework allowed us to develop comprehensive national reports by conducting semi-structured interviews to key informants. These reports were summarised and analysed in a comparative analysis. The study showed that the regulatory framework for clinical research in these countries differ in scope. It showed that despite the different political contexts, actors involved and motivations for creating the regulation, in most of the studied countries it was the government who took the lead in setting up the system. The study also showed that Europe and Latin America are similar regarding national bodies and research ethics committees, but the Brazilian system has strong and noteworthy specificities.

Government programs for treating stroke in Chile

In most Latin America countries and throughout the Caribbean, stroke is a major public health problem. The age-adjusted stroke mortality rates in this region are more than double the rates in the United States or other industrialized nations (1); Chile is no exception. In 2003, 9 6% of all deaths were due to stroke, which represented the second overall cause of mortality (2) with a standardized mortality rate of 55 per 100 000 (3). That year, 19 000 patients were discharged with a diagnosis of stroke, corresponding to 1% of all hospital discharges (4). A study of the burden of disease in Chile showed that in 1993, cerebrovascular disease ranked fifth among the diseases with most DALY’s lost per 1000 (5). In the past decade, several local efforts have been made to attempt to manage this increasing public health problem. In 2002, a second edition of an original study was made public through the Internet; the Cerebrovascular Study Group of the Chilean Society of Neurology, Psychiatry and Neurosurgery (SONEPSYN) coordinated an evidence-based publication on management clinical guidelines (6). These guidelines were reviewed by an officially appointed commission working together with the Non Communicable Diseases Program of the Ministry of Health (7). In 2005, the results were published of a population-based study undertaken in the northern city of Iquique, Chile (8). The study showed that the age-adjusted incidence of total stroke was 1 7 per 1000 and 1 4 per 1000 of first ever stroke. The 30-day case fatality rate was 23%, and 32% had died or were permanently disabled 6 months after the incidence of stroke (8). If we make a projection based on the study of the burden of stroke on the total Chilean population of 16 million, each year, 25 000 persons would suffer a stroke, of whom 70% would be hospitalized, 9000 would die and 6000 would be disabled or dead after 6 months. The study also showed that the prevalence of cardiovascular risk factors such as hypertension and diabetes was high in this cohort, and that the incidence and distribution of pathological subtypes of strokes were similar to other population-based studies, with a slightly lower risk of ischemic stroke and a higher proportion of intracerebral hemorrhage. Differences in the prevalence or mean population levels of cardiovascular risk factors compared with other populations probably account for differences in pathological subtypes of strokes, especially a lower risk of ischemic strokes. Chile has a long tradition of public health initiatives and a very strong public health system, where roughly 80% of the population receives adequate health care. Notwithstanding, a very significant change has come from Ministry of Public Health in recent years. In 2003, the National Health Reform (9) voted and approved in Congress, among other laws, the Explicit Health Guarantees (GES in Spanish). This reform is aimed at addressing inequities in the access to health care, particularly for the 56 conditions that are responsible for the largest proportion of burden of disease affecting the Chilean population. Also considered when the government priorities were defined were the social stigmas attached to these conditions and the availability of effective interventions for treating or preventing them. Stroke was considered as a part of these priorities after a stepwise process that included the measurement of the burden of disease attributable to this condition. A systematic review externally commissioned by the Ministry of Health was coordinated to address the effectiveness of available interventions, and to evaluate the preparedness to respond to the challenge of treating all patients suffering stroke. In the case of stroke, the process began in 2004 with the commission of a systematic review of world literature and consequent report by an academic panel of experts, who then made recommendations on prevention, management, rehabilitation and organization of stroke care based on the best available published evidence. It continued with the publication by the Ministry of Health of clinical guidelines for the management of ischemic stroke in January 2006 (10). The process was complete by July 2006, with the enactment of a number of legal measures attempting to entitle all patients suffering from an ischemic stroke better access to timely treatment and to a set of predefined interventions (11) including the following: Correspondence: Pablo M. Lavados , Neurology Service, Department of Medicine, Clı́nica Alemana de Santiago-UDD. Av. Manquehue Norte 1410, 6th floor, Vitacura. 7650567 Santiago, Chile. Tel: 56 221 010 61; Fax: 56 221 010 60; e-mail: pablolavados@yahoo.com Servicio de Neurologı́a, Departamento de Medicina, Clı́nica Alemana de Santiago-UDD Department of Neurological Sciences, School of Medicine, University of Chile Escuela de Salud Pública, Faculty of Medicine, University of Chile Department of Neurological Sciences, School of Medicine, University of Chile. Ministerio de Salud, Chile Dipreca Hospital, President Cerebrovascular Diseases Study Group, Chilean Society of Neurology, Psychiatry and Neurosurgery

Análisis del cumplimiento de la Guía Clínica del AUGE en pacientes con accidente cerebrovascular isquémico: la utilización de tecnología sanitaria de diagnóstico para prevención secundaria en un hospital público

Background: Acute ischemic stroke in adults was given an Explicit Guarantee of diagnosis and treatment (GES) with Clinical Guidelines in 2007 as part of the on-going Chilean National Health Reform. Aim: To evaluate the adherence to official guidelines with regard to the use of diagnostic methods for patients with acute ischemic stroke during their stay in a public hospital. Patients and Methods: The study included a review of the medical records of 101 patients aged 70 ±13 years (49 males and 52 females) diagnosed with acute ischemic stroke and discharged within August and September of 2008 and 2009 from a public hospital. Three trained ob-servers independently determined the degree of dependency of patients at discharge using the Modified Rankin score. The completion of recommended diagnostic tests (electrocardiogram, carotid Doppler ultrasound and echocardiogram) as well as their overuse was evaluated. Results: Ten patients died before discharge, 38% were discharged with and 52% were discharged without disabilities. Nineteen percent of patients with a Modified Rankin score of two or less (corresponding to a slight disability) had a complete diagnostic workup, compared with 87% of patients with a score of 3 to 5 (moderate to severe disability). In 27% of the patients, there was an overuse of diagnostic tests. No association between the diagnostic test use adequacy and year of discharge was observed. Conclusions: There exists a disparity between the recommended diagnostic testing and the actual tests completed among patients with acute ischemic stroke.

Cerebral ring enhancing lesion with diffusion restriction in a South American patient

The differential diagnosis of cerebral ring enhancing lesions is usually challenging and involves the use of multiple paraclinical tools such as central nervous system (CNS) imaging and cerebrospinal fluid (CSF) studies [1,2]. These lesions can be the manifestation of a variety of pathologies, including infection, primary or secondary neoplastic processes and demyelinating diseases, amongst others. By using conventional magnetic resonance imaging (MRI), an accurate diagnosis of ring enhancing lesions is often difficult. Therefore, the use of novel imaging techniques plays a crucial role in fully characterizing and identifying the underlying pathology of such ring enhancing lesions. A 23-year-old man from the south of Chile was admitted to our Department of Neurology in Santiago, with a history of 2 weeks of multiple self-limiting episodes of involuntary clonic movements of his right face and arm, and one single episode of generalized tonic–clonic seizure. On admission, his vital signs and general examination were unremarkable. Initial neurological examination revealed mild right hemiparesis (MCR score 4) with symmetrical tendon reflexes and an ipsilateral up-going plantar reflex. Cranial nerves and sensory function were normal. Complete blood count, erythrocyte sedimentation rate and C-reactive protein were normal, together with negative antibody testing for HIV, Hepatitis B and C, and VDRL. CSF analysis showed 4.8 leukocytes per microliter, protein of 0.27 g/L, normal glucose levels, and a negative Gram stain and culture. The brain MRI showed one cortico-subcortical lesion in the left precentral frontal region (Fig. 1), mildly hyperintense to CSF on T1-weighted image, hyperintense on T2-weighted image and fluid-attenuated inversion recovery (FLAIR) image,

Contents Vol. 34, 2010

270 Regional North American Annual Meeting of the World Federation of Neurology – Research Group on Neuroepidemiology Editors: Marras, C. (Toronto); Louis, E. (New York, N.Y.); Leimpeter, A.; Van Den Eeden, S.K. (Oakland, Calif.) (only available online) 279 Author Index Vol. 34, 2010 280 Subject Index Vol. 34, 2010