Incidence Rate Of First-ever Stroke Research Articles

Incidence, subtypes, sex differences and trends of stroke in Taiwan.

Chinese populations have been reported higher incidence of all strokes and intracerebral hemorrhage. However, few large-scale studies have evaluated changes of stroke epidemiology in the 21st century. We explored the rates of incidence of all first-ever strokes, subtypes, and 1-month case fatality by using data from the Taiwan National Health Insurance Research Database since 2004. Also, we investigated sex differences in stroke. Time-trend analysis was performed for incidence and case fatality rates of all strokes and subtypes in both sexes. The age-adjusted incidence of all strokes per 100,000 person-years decreased by 16%, from 251 (95% confidence interval [CI] 249-253) in 2004 to 210 (95% CI 209-212) in 2011 (p<0.001); it was always higher in Chinese men than in women. Among pathological subtypes, the incidence of intracerebral hemorrhage markedly decreased by 26% over the years (p<0.001), while that of ischemic stroke slightly decreased by 8%. However, when stratified by sex, the incidence of ischemic stroke decreased significantly in only women, not in men (men: p = 0.399, women: p = 0.004). Regarding the incidence of subarachnoid hemorrhage, it remained unchanged. Furthermore, the rate of 1-month case fatality decreased significantly for all strokes in both sexes (p<0.001). In Taiwan, the incidence rate of first-ever stroke decreased in both Chinese men and women in the early 21st century. Men had a higher incidence rate than women. Furthermore, a marked decrease was noted in the incidence of intracerebral hemorrhage, while a slight decrease was noted in that of ischemic stroke; however, the decreased incidence of ischemic stroke was significant in only women.

Seasonal Variation in Incidence of Stroke in a General Population of 1.4 Million Japanese: The Shiga Stroke Registry

Introduction: The purpose of this study was to investigate seasonal variation in stroke incidence using data from a large-scale stroke registry of general population in current Japan. Methods: Shiga Stroke Registry (SSR) is an ongoing population-based registry of stroke that occurred in the Shiga Prefecture in central Honshu, Japan. A total 6,688 cases of first-ever stroke, with onset dates ranging from 1 January 2011 to 31 December in 2013 were included in this study. Incidence rates of first-ever stroke in each season were estimated using the person-year approach and adjusted for age and sex using the Poisson regression models. Results: From 2011 to 2013, we identified a total of 6,688 stroke cases (3,570 men, 3,118 women), of which 4,480 cases had ischemic stroke (2,518 men, 1,962 women), 1,588 had intracerebral hemorrhage (857 men, 731 women) and 563 had subarachnoid hemorrhage (166 men, 397 women). Age- and sex-adjusted incidence rates of total stroke were 151 (95% confidence interval [CI] 144–160, p = <0.001 vs. summer) in spring, 130 (95% CI 122–137) in summer, 141 (95% CI 133–149, p = 0.020 vs. summer) in autumn and 170 (95% CI 161–179, p = <0.001 vs. summer) in winter. Seasonal variation was more pronounced in intracerebral hemorrhage than in ischemic stroke. Conclusion: In the present large-scale stroke registry of general population, incidence rates of stroke were highest in winter and lowest in summer in current Japan.

Incidence, risk factors, prognosis, and health-related quality of life after stroke in a low-resource community in Chile (ÑANDU): a prospective population-based study

Stroke is a leading cause of disability and death worldwide. The best estimates of local, national, and global burden of stroke are derived from prospective population-based studies. We aimed to investigate the incidence, risk factors, long-term prognosis, care, and quality of life after stroke in the Ñuble region of Chile. We did a prospective community-based study with use of multiple overlapping sources of hospitalised, ambulatory, and deceased cases. Standardised diagnostic criteria were used to identify and follow up all cases occurring in the resident population of the Ñuble region, Chile (in a low-income rural-urban population including predominantly people of Indigenous-European heritage), for 1 year. Participants were included if they had a clinical diagnosis of stroke confirmed according to the study criteria. All cases were adjudicated by vascular neurologists. Incidence rates of first-ever stroke were calculated from the population of Ñuble according to the 2017 national census. From April 1, 2015, to March 31, 2016, we ascertained 1103 stroke cases, of which 890 (80·7%) were first-ever incident cases. The mean age of patients with first-ever stroke was 70·3 years (SD 14·1) and 443 (49·8%) were women. A CT scan was obtained in 801 (90%) of 890 patients (mean time from symptom onset to scan of 13·4 h (SD 29·8). The incidence of first-ever stroke age-adjusted to the world population was 121·7 (95% CI 113·7-130·1) per 100 000. The age-adjusted incidence rates, per 100 000 inhabitants, by main pathological subtypes were as follows: ischaemic stroke (101·5 [95% CI 90·9-113·0]); intracerebral haemorrhage (17·9 [13·5-23·4]), and subarachnoid haemorrhage (4·2 [2·1-7·3]). The 30-day case-fatality rate was 24·6% (21·9-27·6). At 6 months after the stroke, 55·9% (432 of 773) of cases had died or were disabled, which increased to 61·0% (456 of 747) at 12 months. Health-related quality of life in survivors was low at 6 months, improving slightly at 12 months after the stroke. The incidence of stroke in this low-resource population was higher than our previous finding in northern Chile and within the mid-range of most population-based stroke studies. This result was due mainly to a higher incidence of ischaemic stroke, probably associated with increasing age and a high prevalence of cardiometabolic risk factors in the population studied. Our findings suggest that more should be done for the prevention and care of stroke in communities like the Ñuble population. The National Agency for Research and Development and the Technology-Health Research Fund, Clínica Alemana de Santiago, Boehringer Ingelheim, Bristol Meyers Squibb, The Herminda Martin Clinical Hospital of Chillán, Universidad Mayor, and Universidad de Concepción.

Population-Based Incidence Rates of First-Ever Stroke in Central Vietnam.

IntroductionStroke incidence data with methodologically acceptable design in Southeast Asia countries is limited. This study aimed to determine incidence of age-, sex- and subtype-specific first-ever stroke (FES) in Vietnam.MethodsWe conducted a hospital-based retrospective study, targeting all stroke cases hospitalized at a solo-provider hospital in our study site of Nha Trang from January 2009 to December 2011 with International Classification of Diseases, 10th revision (ICD-10) codes I60-69. We calculated positive predictive values (PPVs) of each ICD-10-coded stroke by conducting a detailed case review of 190 randomly selected admissions with ICD-10 codes of I60-I69. These PPVs were then used to estimate annual incident stroke cases from the computerized database. National census data in 2009 was used as a denominator.Results2,693 eligible admissions were recorded during the study period. The crude annual incidence rate of total FES was 90.2 per 100,000 population (95% CI 81.1–100.2). The age-adjusted incidence of FES was 115.7 (95% CI 95.9–139.1) when adjusted to the WHO world populations. Importantly, age-adjusted intracerebral hemorrhage was as much as one third of total FES: 36.9 (95% CI 26.1–51.0).ConclusionsWe found a considerable proportion of FES in Vietnam to be attributable to intracerebral hemorrhage, which is as high or exceeding levels seen in high-income countries. A high prevalence of improperly treated hypertension in Vietnam may underlie the high prevalence of intracerebral hemorrhagic stroke in this population.

Stroke surveillance: population‐based estimates and projections for New Zealand

To estimate the incidence, prevalence and mortality of stroke in New Zealand (NZ) in 2001, projected to 2011. Multistate lifetable models were constructed using smoothed rates of first-ever stroke incidence and relative risks of mortality estimated from the most recent Auckland Regional Community Stroke (ARCOS) Study. Estimates of the burden of stroke in NZ were calculated by applying rates output by the model to the 2001 population. Stroke incidence, prevalence and mortality were then projected to 2011, assuming similar trends in stroke incidence and case fatality to those estimated between the 1991/92 and 2002/03 studies. A total of 5,200 first-ever strokes were estimated to have occurred in NZ in 2001. Rates of stroke rose exponentially with increasing age and were 20% higher among males than females at most ages. Nevertheless, the lifetable risk of stroke was lower for males (16%) than females (18%). On average, males survived a year longer than females after a first-ever stroke (9.0 vs. 8.2 years). The incidence rates of first-ever stroke declined by approximately 1% per year between 1991 and 2003. The lifetable risk of stroke remained stable for females but increased for males (from 14% to 16%) over this period. Stroke prevalence also increased by approximately 1% per year, whereas stroke-related mortality fell by 4% per year. If these trends continue, approximately 6,000 first-ever strokes (2% annual increase), 45,000 stroke survivors (2% annual increase) and 2,000 stroke-related deaths (1% annual decline) are expected in 2011. Stroke mortality is falling faster than stroke incidence. This, together with population growth and ageing, will lead to a rising burden of stroke-related disability over the next decade.

Evidence for Age-Dependent Education-Related Differences in Men and Women with First-Ever Stroke

Several studies have shown a relationship between low socioeconomic status, age and stroke mortality. However, there is lack of similar studies in relation to stroke incidence. All cases of first-ever stroke occurring in a population aged 35–85 years from the city of Umeå were collected from hospital-based registers during a 2-year study period (2000–2002), from death certificates and also from nursing homes during a 6-month period. The WHO definition of stroke was used. Register data served to analyze educational level. A total of 457 first-ever strokes (244 women and 213 men) were registered, corresponding to an overall annual incidence rate of first-ever stroke of 413.4 per 100,000. The incidence of first-ever stroke was significantly higher among low-educated compared to high-educated men and women. The highest stroke incidence was found among low-educated women aged 75–85 years. The educational-related differences in stroke incidence persisted in the oldest age group (75–85 years), also after controlling for sex and age. This is one of the first studies that analyzes first-ever stroke incidence also among elderly men and women (75–85 years) in relation to socioeconomic status. More community-based studies are needed in order to confirm the results.

Incidence, 30-day case-fatality rate, and prognosis of stroke in Iquique, Chile: a 2-year community-based prospective study (PISCIS project)

The epidemiology of stroke in Latin-American populations and variation of subtypes between communities are unclear. Our aim was to ascertain prospectively the incidence of first-ever stroke in the predominantly Hispanic-Mestizo population of Iquique, a city in the northern desert region of Chile. We prospectively identified all possible cases of stroke and transient ischaemic attacks between July 1, 2000, and June 30, 2002, from several overlapping sources. Patients were rapidly assessed by two field neurologists. Standard definitions for incident cases, stroke, transient ischaemic attack, pathological type, and infarction subtype were used. All cases identified were adjudicated by at least two stroke neurologists and followed up at 6 months. Incidence rates of first-ever strokes were calculated from the population of Iquique (214 526) according to the national census of 2002. Of 380 cases of stroke identified, 292 were incident. CT scans were done in 267 (91%) patients and the mean time to scan was 2.2 days. The hospital admission rate was 71% (207/292). The overall age-adjusted incidence rate of first-ever stroke was 140.1 per 100,000 (95% CI 124.0-156.2). The incidence rates per 100,000 according to pathological type were: infarcts 87.3, intracerebral haemorrhage 27.6, and subarachnoid haemorrhage 6.2. The 30 day and 6-month case-fatality rates were 23.3% and 33.0%, respectively. Our results show incidence rates of stroke similar to those reported in other community studies. Although the proportion of intracerebral haemorrhages was higher than reported in previous studies, the overall incidence was not, which could indicate a slightly lower incidence of ischaemic strokes in this population than in other countries. The prognosis was similar to that found in other population-based studies.

Incidence, risk factors and short-term mortality of stroke in Vittoria, southern Italy.

We determined the incidence, risk factors, and short-term mortality of stroke in a well-defined area of southern Italy, i. e. the city of Vittoria, Sicily (58 833 inhabitants). The medical recores of the local hospitals and the outpatient files of the local neurologist referring to the calendar year 1991 were retrospectively investigated. Stroke was defined according to standard criteria and classified as first-ever (FE) and recurrent (R). Risk factors for stroke were diagnosed from medical history, laboratory and instrumental findings, and in the presence of specific treatments. Short-term mortality was assessed as 30-day case-fatality rate. The sample included 120 cases (61 men) aged 34-94 years, 89 of whom (48 men) had a FE stroke. The overall annual crude incidence rate of FE stroke was 165.3 per 100 000 (men, 178.4; women 152.2); for FE and R stroke together it was 222.9 (men, 226.8; women 219.1). The standardized rates were 245.3 (FE stroke) and 321.9 (FE and R stroke). The age-specific rates for FE stroke were 9.4 (<55 years), 262.2 (55-64 years), 645.2 (65-74 years), 2019.7 (75-84 years), and 3246.8 (> or =85 years). The corresponding values for FE and R stroke were 11.7, 412.0, 887.1, 2565.5, and 4220.8. In patients with FE stroke, cerebral infarction was the main type. Hypertension, diabetes and cardiac disorders were the commonest risk factors, with similar distribution among FE and R stroke. The 30-day case-fatality rate was 28% for FE and R stroke and 38% for FE stroke. Compared to other reports, the incidence of stroke in Vittoria was lower in the youngest but higher in the oldest age groups. Although the small sample size and possibility of misdiagnoses may partly explain our findings, the roles of different dietary, social, and genetic factors in the local population warrant investigation.

Proportion of Older People in the Community as a Predictor of Increasing Stroke Incidence

Objectives: To compare stroke incidence rates among comparable registries and to make correlations with aging of the resident populations. Methods: This correlation study included all comparable stroke registries maintained in industrialized countries (Italy, France, United Kingdom, Denmark, Norway, United States, and Australia). Eleven community-based stroke registries with similar high proportions of radiologically confirmed diagnoses based on standard definitions were identified. Incidence rates of first-ever stroke from the prospective L’Aquila registry and from the other registries were compared after age and sex standardization to the 1996 European population. The rates were then correlated with the proportion of individuals aged 65 and over in the corresponding resident populations by means of the Poisson regression analysis. Results: In the L’Aquila registry, the crude annual incidence of first-ever stroke was 281/100,000 (95% confidence interval 271–293) based on 2,515 patients included during a 3-year period. The rate standardized to the European population was 249/100,000. Standardized incidence ratios indicated a significant excess of first-ever strokes in the L’Aquila registry up to 51% with respect to most of the compared studies. A significant correlation was also found between crude (p < 0.0001) and standardized (p = 0.0012) stroke incidence rates and proportions of individuals aged 65 and over in the different populations. Conclusions: The L’Aquila experience suggests that any further aging of a population will increase the stroke occurrence for both the reasons of a direct and predictable effect of the growing proportion of elderly individuals within that population and a disproportionately increased stroke risk in the older age groups.

Incidence of Stroke on Kinmen, Taiwan

This study aims to assess the incidence, case-fatality rate and risk factors of stroke on Kinmen Island, Taiwan, from 1993 to 1996. A population-based stroke survey was carried out in 1993 and 1996 to collect data on all subjects in the population aged 50 years and older residing on Kinmen. There were 63 stroke events (53 first ever and 10 recurrent) identified in this period. The average annual incidence rate of first-ever stroke for people aged 50 years or older was 527 per 100,000 population (95% confidence interval, CI, 297–757). The 28-day case-fatality rate was 24.5% (95% CI 12.9–36.1%) for first-ever stroke and 60% (95% CI 29.6–90.4%) for recurrent stroke. Multivariate analyses performed with the Cox proportional hazard model revealed the following risk factors to be independent predictors of stroke: hypertension, diabetes and alcohol use. The incidence and case- fatality rate of stroke on Kinmen is similar to that of several other countries. Hypertension is the most common risk factor in this population. Due to a relatively small number of outcome events, these findings require confirmation.

Epidemiology of stroke in Innherred, Norway, 1994 to 1996. Incidence and 30-day case-fatality rate.

In Norway, as well as other industrialized countries, mortality from stroke has declined over the past decades. Data on stroke morbidity are lacking. This study was conducted to determine the incidence, case fatality, and risk factors of stroke in a defined Norwegian population. During the period 1994 to 1996, a population-based stroke registry collected uniform information about all cases of first-ever and recurrent stroke occurring in people aged > or = 15 years in the region of Innherred in the central part of Norway (target population 70,000), where the prevalence of cardiovascular risk factors was screened in 1984 to 1986 and 1995 to 1997. During the 2 years of registration (September 1, 1994, to August 31, 1996), 432 first-ever (72.8%) and 161 recurrent (27.2%) strokes were registered. The crude annual incidence rate was 3.12/1000 (2.85/1000 for males and 3.38/1000 for females). Adjusted to the European population, the annual incidence rate of first-ever stroke was 2.21/1000. The annual incidence rate of cerebral infarction was 2.32/1000, intracerebral hemorrhage 0.32/1000, subarachnoid hemorrhage 0.19/1000, and unspecified stroke 0.38/1000. The 30-day case-fatality rate was 10.9% for cerebral infarction, 37.8% for intracerebral hemorrhage, and 50.0% for unspecified stroke. Fourteen percent of the patients were found outside the hospital, and only 50% of the suspected stroke cases in the hospital (at admission or reviewed discharge diagnosis of ICD-9 codes 430 to 438) fitted the final inclusion criteria. This first population-based stroke register in Norway revealed incidence rates of stroke similar to other Scandinavian countries, and comparison between other European countries did not indicate regional variations within Western Europe.

Stroke epidemiology in Novosibirsk, Russia: a population-based study.

To determine first-ever stroke incidence, 30-day case-fatality rates, and frequency of various risk factors among patients with stroke in Novosibirsk, Russia, during 1992. A population-based study of an administratively defined district of Novosibirsk was conducted to identify residents with a first-ever stroke that occurred between Jan. 1, 1992, and Dec. 31, 1992. For case ascertainment, mortality statistics, death certificates, hospital registrations, outpatient clinical data, and all ambulance calls for the study area were reviewed. Patients with stroke or suspected stroke were examined and interviewed by a cerebrovascular neurologist, and the type of stroke was determined. During the 12-month study period, 366 patients with first-ever stroke were registered. A diagnosis of cerebral infarction or intracerebral hemorrhage was confirmed by computed tomography or autopsy in 42% of cases. The diagnosis of subarachnoid hemorrhage was established by cerebrospinal fluid examination in all 14 cases. The age- and sex-adjusted annual incidence rate for stroke was 232 per 100,000. The distribution of incidence cases by diagnostic category was as follows: cerebral infarction, 87.7%; intracerebral hemorrhage, 8.5%; and subarachnoid hemorrhage, 3.8%. The overall 30-day case-fatality rate for stroke was 22.4%. Hypertension, angina pectoris, and cigarette smoking were the most frequent risk factors in patients with stroke in Novosibirsk. The incidence rate of first-ever stroke in Novosibirsk, Russia, is one of the highest in the world, but the 30-day case-fatality rates are similar to those in other populations.

Incidence of stroke among inpatients in a large Italian hospital.

The incidence of stroke among inpatients is not known. The aim of our study was to investigate the incidence of stroke not preceded by evident iatrogenic factors such as surgical or medical procedures in a cohort of inpatients in a large Italian general hospital. From January 1, 1992, to December 31, 1992, we evaluated patients referred to our neurology department with a suspected diagnosis of stroke that occurred during hospitalization. Patients presenting with stroke as a complication of iatrogenic causes were excluded. We calculated the incidence rate of first-ever stroke in our cohort (crude and among patients aged older than 50 years), thereafter adjusting these rates for age to the general population of the city district of Bologna (Italy). In 1992, 22 inpatients had a first-ever stroke with no evidence of iatrogenic factors. The crude stroke incidence rate was 11.08/1000 per year (95% confidence interval, 6.95 to 16.73). The age-adjusted rate was 5.46 (95% confidence interval 3.42 to 8.24). The incidence rate of first-ever stroke among hospitalized patients is higher than those reported in community-based studies. Higher frequency of coronary artery disease among our patients could explain our findings. Further studies are needed to identify possible predisposing factors (individual or environmental) for stroke among inpatients.

Stroke incidence rates were unchanged, while fatality rates declined, during 1971-1987 in Göteborg, Sweden.

Stroke risk factors have been shown to change with time in several places; simultaneously, stroke incidence rates have increased in some and decreased in other places. In Göteborg, Sweden, cardiovascular epidemiological research has included stroke registration since 1971. From these data on stroke, incidence and fatality rates from a 17-year period are given. During the period 1971-1987 all cases of stroke occurring in people aged 15-65 years in the city of Göteborg were uniformly recorded, with an estimated case detection rate of 90% or more. Age-adjusted incidence rates of first-ever stroke by sex did not change during the period. Age-specific rates and rates for individual types of stroke (subarachnoid hemorrhage, intracerebral hemorrhage, and cerebral infarction-unspecified stroke combined) were also largely unchanged. A slight increase in the incidence rate of intracerebral hemorrhage may be due to better detection after computed tomography came into use in 1976. Stroke fatality rates declined through the whole period in both sexes and all age groups, markedly so for intracerebral hemorrhage and subarachnoid hemorrhage. This conforms with vital statistics for Göteborg and for Sweden of declining stroke mortality during the period. The decline in stroke fatality rates may be related to decreases in smoking habits and blood pressure together with an increase in the percentage of people on antihypertensive treatment among middle-aged men, and to some extent even middle-aged women, reported from the same population. Why stroke incidence rates did not decline concomitantly is unexplained.

Incidence of stroke in Taiwan.

Few epidemiological studies concerning the incidence of stroke have been conducted in Taiwan. In an attempt to investigate this common disease, we studied the incidence of stroke in Taiwan in a prospective incidence study. A cohort of 8,562 stroke-free people were followed up for 4 years to observe new stroke occurrence. The methods of sampling the study population have been reported elsewhere. In addition to the help of local doctors, who reported the new stroke cases, we also sent public nurses to visit the study population annually to screen the new cases of stroke. There were 104 (61 men and 43 women) first-ever stroke cases identified by a neurologist in a period between October 1, 1986 and December 31, 1990. The average annual incidence rate of first-ever stroke for people aged 36 years or older in this study was 330 per 100,000. Incidence rate was higher in eastern Taiwan and in rural communities. Percentages of the major types of stroke were as follows: cerebral infarction, 71%; cerebral hemorrhage, 22%; subarachnoid hemorrhage, 1%; and unclassified, 6%. The significant risk factors for stroke were hypertension and intake of food with a high sodium content. The age-specific incidence rates in this study are higher than those reported from the United Kingdom and the United States. The rates are close to those in a report from Japan and a report from a city in mainland China at the same latitude. Cerebral hemorrhages are more common among people in Taiwan than among Occidental people.