Community-based stroke incidence in a Scottish population: the Scottish Borders Stroke Study

Incidence, case fatality, and functional outcome of intracerebral haemorrhage over time, according to age, sex, and ethnic origin: a systematic review and meta-analysis

BACKGROUND

Since the early 1980s, imaging techniques have enabled population-based studies of intracerebral haemorrhage. We aimed to assess the incidence, case fatality, and functional outcome of intracerebral haemorrhage in relation to age, sex, ethnic origin, and time period in studies published since 1980.

METHODS

From PubMed and Embase searches with predefined inclusion criteria, we identified population-based studies published between January, 1980, and November, 2008. We calculated incidence and case fatality. Incidences for multiple studies were pooled in a random-effects binomial meta-analysis. Time trends of case fatality were assessed with weighted linear-regression analysis.

FINDINGS

36 eligible studies described 44 time periods (mid-year range 1983-2006). These studies included 8145 patients with intracerebral haemorrhage. Incidence did not decrease between 1980 and 2008. Overall incidence was 24.6 per 100 000 person-years (95% CI 19.7-30.7). Incidence was not significantly lower in women than in men (overall incidence ratio 0.85, 95% CI 0.61-1.18). Using the age group 45-54 years as reference, incidence ratios increased from 0.10 (95% CI 0.06-0.14) for people aged less than 45 years to 9.6 (6.6-13.9) for people older than 85 years. Median case fatality at 1 month was 40.4% (range 13.1-61.0) and did not decrease over time, and was lower in Japan (16.7%, 95% CI 15.0-18.5) than elsewhere (42.3%, 40.9-43.6). Six studies reported functional outcome, with independency rates of between 12% and 39%. Incidence of intracerebral haemorrhage per 100 000 person-years was 24.2 (95% CI 20.9-28.0) in white people, 22.9 (14.8-35.6) in black people, 19.6 (15.7-24.5) in Hispanic people, and 51.8 (38.8-69.3) in Asian people.

INTERPRETATION

Incidence of intracerebral haemorrhage increases with age and has not decreased between 1980 and 2006. Case fatality is lower in Japan than elsewhere, increases with age, and has not decreased over time. More data on functional outcome are needed.

FUNDING

Netherlands Heart Foundation.

Excessive Incidence of Stroke in Iran

Background and Purpose— The epidemiology of stroke and its subtypes in the Middle East is unclear. Most previous studies have been performed in Western countries, and incidence rates are unlikely to apply in the Middle East. We aimed to determine the incidence of stroke in Mashhad, northeastern Iran.

Methods— During a 12-month period (2006–2007), we prospectively ascertained all strokes occurring in a population of 450 229. Multiple overlapping sources were used to identify people with stroke. A large number of volunteers assisted in finding stroke patients not admitted to hospital. Potential cases were reviewed by a group of stroke experts before inclusion.

Results— A total of 624 first-ever strokes occurred during the study period, 98.4% undergoing imaging. Despite a relatively low crude annual incidence rate of first-ever stroke FES (139; 95% CI, 128 to 149) per 100 000 residents, rates adjusted to the European population aged 45 to 84 years were higher than in most other countries: 616 (95% CI, 567 to 664) for ischemic stroke, 94 (95% CI, 75 to 113) for intracerebral hemorrhage, and 12 (95% CI, 5 to 19) for subarachnoid hemorrhage. Age-specific stroke incidence was higher in younger patients than is typically seen in Western countries. Comparison of age-specific incidence rates between regions revealed that stroke in Mashhad occurs approximately 1 decade earlier than in Western countries.

Conclusions— The results of this study provide evidence that the incidence of stroke in Iran is considerably greater than in most Western countries, with stroke occurring at younger ages. Ischemic stroke incidence was also considerably greater than reported in other regions.

Incidence and Case Fatality of Subarachnoid Haemorrhage in Northern Greece: The Evros Registry of Subarachnoid Haemorrhage

Background

Epidemiological data on subarachnoid haemorrhage incidence and case-fatality rates are scarce in the southeastern Mediterranean region. We conducted a population-based study in Evros Province, located in north-eastern Greece, to determine subarachnoid haemorrhage incidence over a 5-year period (2001–2005).

Methods

Evros Province has a well-defined, largely homogeneous population with healthcare organised around a single tertiary-care University Hospital. We organised a prospective computerised registry of permanent Evros residents admitted or transferred to our hospital with a diagnosis of subarachnoid haemorrhage. Standard World Health Organization definitions and overlapping case-finding methods were used to identify all cases of first ever in a lifetime subarachnoid haemorrhage in all age groups, occurring during the study period. The diagnosis was confirmed by computed tomography scan in all hospitalised cases. Sudden deaths attributable to subarachnoid haemorrhage were systematically recorded province-wide by our forensic department and are included in the study.

Results

During the 5-year period, 51 cases of subarachnoid haemorrhage were recorded (28 men, 23 women; mean age 59 ± 17 years). The crude annual incidence rates were 8·3/100000 persons (95% confidence interval: 5·5–12·0) for men, 7·5/100000 (4·8–11·3) for women and 7·9/100000 (5§9–10§4) for all subjects. The standardised incidence rates for groups aged 45–84 years in the European population were 9·3/100000 (5·8–12·8) for men, 6·5/100000 (3·7–9·4) for women and 7·9/100000 (5·7–10·2). The 28-day case-fatality rates for men, women and all subjects were 36% (21–54%), 35% (19–55%) and 35% (24–49%), respectively.

Conclusions

The incidence and case-fatality rate of subarachnoid haemorrhage haemorrhage in Greece appear to be similar to other developed countries. No gender differences in subarachnoid haemorrhage incidence and case-fatality rate were documented.

Changes in case fatality of aneurysmal subarachnoid haemorrhage over time, according to age, sex, and region: a meta-analysis

BACKGROUND

In a systematic review, published in 1997, we found that the case fatality of aneurysmal subarachnoid haemorrhage (SAH) decreased during the period 1960-95. Because diagnostic and treatment strategies have improved and new studies from previously non-studied regions have been published since 1995, we did an updated meta-analysis to assess changes in case fatality and morbidity and differences according to age, sex, and region.

METHODS

A new search of PubMed with predefined inclusion criteria for case finding and diagnosis identified reports on prospective population-based studies published between January, 1995, and July, 2007. The studies included in the previous systematic review were reassessed with the new inclusion criteria. Changes in case fatality over time and the effect of age and sex were quantified with weighted linear regression. Regional differences were analysed with linear regression analysis, and the regions of interest were subsequently defined as reference regions and compared with the other regions.

FINDINGS

33 studies (23 of which were published in 1995 or later) were included that described 39 study periods. These studies reported on 8739 patients, of whom 7659 [88%] were reported on after 1995. 11 of the studies that were included in the previous review did not meet the current, more stringent, inclusion criteria. The mean age of patients had increased in the period 1973 to 2002 from 52 to 62 years. Case fatality varied from 8.3% to 66.7% between studies and decreased 0.8% per year (95% CI 0.2 to 1.3). The decrease was unchanged after adjustment for sex, but the decrease per year was 0.4% (-0.5 to 1.2) after adjustment for age. Case fatality was 11.8% (3.8 to 19.9) lower in Japan than it was in Europe, the USA, Australia, and New Zealand. The unadjusted decrease in case fatality excluding the data for Japan was 0.6% per year (0.0 to 1.1), a 17% decrease over the three decades. Six studies reported data on case morbidity, but these were insufficient to assess changes over time.

INTERPRETATION

Despite an increase in the mean age of patients with SAH, case-fatality rates have decreased by 17% between 1973 and 2002 and show potentially important regional differences. This decrease coincides with the introduction of improved management strategies.

FUNDING

Netherlands Organisation for Scientific Research; ZonMw.

Importance of cardiovascular risk profile for in-hospital mortality due to cerebral infarction

INTRODUCTION AND OBJECTIVES

To investigate cardiovascular risk profiles and their prognostic implications in patients with different subtypes of cerebral infarction.

METHODS

The study involved the retrospective analysis of data from a hospital stroke registry on 2704 consecutive CI patients who were admitted between 1986 and 2004. Of the 2704 strokes recorded, 770 were classified as thrombotic, 763 as cardioembolic, 733 as lacunar, 324 as undetermined and 114 as atypical. Multivariate analysis was used to compare cardiovascular risk profiles in each subtype and their influence on inhospital mortality.

RESULTS

Arterial hypertension (AH) was present in 55.5%, atrial fibrillation (AF) in 29.8%, and diabetes mellitus in 23.4%. The in-hospital mortality rate was 12.9%, and in-hospital mortality was independently associated with AF (odds ratio [OR]=2.33; 95% confidence interval [CI], 1.84-2.96), and heart failure (HF) (OR=1.96; 95% CI, 1.33-2.89). In patients with thrombotic stroke, the cardiovascular risk factors associated with in-hospital mortality were HF (OR=2.87; 95% CI, 1.45-5.71), AF (OR=1.80; 95% CI, 1.09-2.96) and age (OR=1.06; 95% CI, 1.04-1.08). In patients with cardioembolic stroke, they were peripheral vascular disease (OR=2.18; 95% CI, 1.17-4.05), previous cerebral infarction (OR=1.75; 95% CI, 1.16-2.63), HF (OR=1.71; 95% CI, 1.01-2.90), and age (OR=1.06; 95% CI, 1.04-1.08). In those with undetermined stroke, they were AH (OR=3.68; 95% CI, 1.78-7.62) and age (OR=1.05; 95% CI, 1.01-1.09).

CONCLUSIONS

Each cerebral infarction etiologic subtype was associated with its own cardiovascular risk profile. Consequently, the cardiovascular risk factors associated with mortality were also different for each ischemic stroke subtype.

Worldwide stroke incidence and early case fatality reported in 56 population-based studies: a systematic review

This systematic review of population-based studies of the incidence and early (21 days to 1 month) case fatality of stroke is based on studies published from 1970 to 2008. Stroke incidence (incident strokes only) and case fatality from 21 days to 1 month post-stroke were analysed by four decades of study, two country income groups (high-income countries and low to middle income countries, in accordance with the World Bank's country classification) and, when possible, by stroke pathological type: ischaemic stroke, primary intracerebral haemorrhage, and subarachnoid haemorrhage. This Review shows a divergent, statistically significant trend in stroke incidence rates over the past four decades, with a 42% decrease in stroke incidence in high-income countries and a greater than 100% increase in stroke incidence in low to middle income countries. In 2000-08, the overall stroke incidence rates in low to middle income countries have, for the first time, exceeded the level of stroke incidence seen in high-income countries, by 20%. The time to decide whether or not stroke is an issue that should be on the governmental agenda in low to middle income countries has now passed. Now is the time for action.

Sex differences in stroke epidemiology: a systematic review

BACKGROUND AND PURPOSE

Epidemiological studies, mainly based on Western European surveys, have shown that stroke is more common in men than in women. In recent years, sex-specific data on stroke incidence, prevalence, subtypes, severity and case-fatality have become available from other parts of the world. The purpose of this article is to give a worldwide review on sex differences in stroke epidemiology.

METHODS

We searched PubMed, tables-of-contents, review articles, and reference lists for community-based studies including information on sex differences. In some areas, such as secular trends, ischemic subtypes and stroke severity, noncommunity-based studies were also reviewed. Male/female ratios were calculated.

RESULTS

We found 98 articles that contained relevant sex-specific information, including 59 incidence studies from 19 countries and 5 continents. The mean age at first-ever stroke was 68.6 years among men, and 72.9 years among women. Male stroke incidence rate was 33% higher and stroke prevalence was 41% higher than the female, with large variations between age bands and between populations. The incidence rates of brain infarction and intracerebral hemorrhage were higher among men, whereas the rate of subarachnoidal hemorrhage was higher among women, although this difference was not statistically significant. Stroke tended to be more severe in women, with a 1-month case fatality of 24.7% compared with 19.7% for men.

CONCLUSIONS

Worldwide, stroke is more common among men, but women are more severely ill. The mismatch between the sexes is larger than previously described.

Low Incidence of Stroke in Southern Italy

Background and Purpose— Although a lower incidence of stroke has been observed in the Mediterranean area compared to other European countries, this is based on only a few studies. We sought to determine the incidence and 28-day case-fatality of stroke through a population-based stroke register in a rural area in Southern Italy, characterized by a stroke unit in the referral hospital.

Methods— We established a multisource prospective population-based register in a well defined geographic area of 38 735 inhabitants in Puglia, Southern Italy. We identified all subjects in the study area with a first-ever stroke between January 1, 2001 and December 31, 2002.

Results— We identified 127 first-ever strokes (77 males, 50 females) during the two-year study period. Hospitalization was 95%: 92 cases (72.4%) were cerebral infarction, 24 (18.9%) intracerebral hemorrhage, 3 (2.4%) subarachnoid hemorrhage, and 8 (6.3%) were unclassifiable strokes. The overall crude annual incidence was 1.6 per 1000 (95%CI: 1.4 to 1.9), 2.0 for males (95% CI:1.6 to 2.5), and 1.3 for females (95% CI:0.9 to 1.6). The incidence rates standardized to the 2001 European and world populations were respectively 1.5 (2.0 for males and 1.3 for females) and 0.8 (0.9 for males and 0.6 for females). Incidence rates progressively increased with age in both sexes, reaching their peak at 85 years or more (21.4/1000 overall, 35.0 for men and 13.4 for women). The 28-day case-fatality was 18.1%.

Conclusions— Our study supports previous findings of lower incidence of stroke in the Mediterranean area, whereas the case-fatality in our study was lower than in previous studies from Italy. Further studies are needed to determine the role of prompt referral and stroke units on prognosis in population-based setting.

The cost of cerebral ischaemia

Cerebral ischaemia is a major cause of disability and death globally and has a profoundly negative impact on the individuals it affects, those that care for them and society as a whole. The most common and familiar manifestation is stroke, 85% of which are ischaemic and which is the second leading cause of death and most common cause of complex chronic disability worldwide. Stroke survivors often suffer from long-term neurological disabilities significantly reducing their ability to integrate effectively in society with all the financial and social consequences that this implies. These difficulties cascade to their next of kin who often become caregivers and are thus indirectly burdened. A more insidious consequence of cerebral ischaemia is progressive cognitive impairment causing dementia which although less abrupt is also associated with a significant long-term disability. Globally cerebrovascular diseases are responsible for 5.4 million deaths every year (1 in 10 of total). Approximately 3% of total healthcare expenditure is attributable to cerebral ischaemia with cerebrovascular diseases costing EU healthcare systems 21 billion euro in 2003. The cost to the wider economy (including informal care and lost productivity) is even greater with stroke costing the UK 7-8 billion pound in 2005 and the US $62.7 billion in 2007. Cerebrovascular disease cost the EU 34 billion euro in 2003. From 2005 to 2050 the anticipated cost of stroke to the US economy is estimated at $2.2 trillion. Given the global scale of the problem and the enormous associated costs it is clear that there is an urgent need for advances in the prevention of cerebral ischaemia and its consequences. Such developments would result in profound benefits for both individuals and their wider societies and address one of the world's most pre-eminent public health issues.

Association of activity limitations and lower-limb explosive extensor power in ambulatory people with stroke

OBJECTIVE

To determine whether the explosive lower-limb extensor power of the affected and unaffected sides, and any asymmetry, are associated with activity limitations after stroke.

DESIGN

Cross-sectional observational study of baseline data from a randomized controlled trial.

SETTING

Measurements made in a hospital clinical research facility.

PARTICIPANTS

Community-dwelling (N=66) subjects with stroke who were independently ambulatory. Subjects' mean age was 72+/-10 years.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The lower-limb extensor power of each lower limb (in W/kg), performance of specific functional activities (comfortable walking velocity, Functional Reach Test, chair-rise time, Timed Up & Go test), and global indices of activity limitation (FIM instrument, Rivermead Mobility Index, Nottingham Extended Activities of Daily Living).

RESULTS

Low lower-limb extensor power in either lower limb was the principal factor from among the confounders we recorded that significantly (R(2) range, .21-.46) predicted the limitation of specific functional activities, and low lower-limb extensor power in either lower limb was the principal predictive factor for global indices of activity limitation (R(2) range, .13-.38). The degree of asymmetry of lower-limb extensor power between legs was low and had little or no predictive value.

CONCLUSIONS

In ambulatory persons with stroke, activity limitations are associated with deficits in lower-limb extensor power of both lower limbs, and not the severity of any residual asymmetry. These findings suggest that interventions to increase lower-limb extensor power in both lower limbs might reduce activity limitations after stroke.

Risk of stroke with typical and atypical anti-psychotics: a retrospective cohort study including unexposed subjects

The purpose of the study was to investigate the risk of stroke with typical and atypical anti-psychotics in elderly subjects, weighting for a number of known risk factors, including dementia. Data were retrospectively drawn from the primary care setting from the Health Search Database, which stores information on about 1.5% of the total Italian population served by general practitioners. All elderly patients (65+ years) prescribed an anti-psychotic in monotherapy from January 2000 to June 2003 were selected for the study. A cohort of patients not exposed to anti-psychotics was taken from the same database. Subjects who had previously had a stroke were excluded. The main outcome measure was the incidence of first-ever stroke during exposure to an anti-psychotic.The sample included non-users (69,939), users of atypicals (599), butyrophenones (749), phenotiazines (907) and substituted benzamides (1,968). The crude incidence of stroke in subjects not exposed to anti-psychotics was 12.0/1000 person-years. Risk was significantly higher for those on butyrophenones (47.1/1000), phenotiazines (72.7/1000) and in the atypical anti-psychotic group (47.4/1000). Substituted benzamides had an almost significant higher risk (25.0/1000). Cox regression modelling, weighting for demographic and clinical variables with non-users as the reference group, showed that the risk for stroke was 5.79 times for phenotiazines, 3.55 times for butyrophenones, and 2.46 times for atypicals. Clinicians should be cautious in prescribing phenotiazines and butyrophenones in elderly patients, since the risk for stroke would seem comparable or even greater than with atypicals.

Incidence of subarachnoid haemorrhage: a systematic review with emphasis on region, age, gender and time trends

BACKGROUND AND AIM

To update our 1996 review on the incidence of subarachnoid haemorrhage (SAH) and assess the relation of incidence with region, age, gender and time period.

METHODS

We searched for studies on the incidence of SAH published until October 2005. The overall incidences with corresponding 95% confidence intervals were calculated. We determined the relationship between the incidence of SAH and determinants by means of univariate Poisson regression.

RESULTS

We included 51 studies (33 new), describing 58 study populations in 21 countries, observing 45,821,896 person-years. Incidences per 100,000 person-years were 22.7 (95% CI 21.9 to 23.5) in Japan, 19.7 (18.1 to 21.3) in Finland, 4.2 (3.1 to 5.7) in South and Central America, and 9.1 (8.8 to 9.5) in the other regions. With age category 45-55 years as the reference, incidence ratios increased from 0.10 (0.08 to 0.14) for age groups younger than 25 years to 1.61 (1.24 to 2.07) for age groups older than 85 years. The incidence in women was 1.24 (1.09 to 1.42) times higher than in men; this gender difference started at age 55 years and increased thereafter. Between 1950 and 2005, the incidence decreased by 0.6% (1.3% decrease to 0.1% increase) per year.

CONCLUSIONS

The overall incidence of SAH is approximately 9 per 100,000 person-years. Rates are higher in Japan and Finland and increase with age. The preponderance of women starts only in the sixth decade. The decline in incidence of SAH over the past 45 years is relatively moderate compared with that for stroke in general.

Stroke incidence, prognosis, 30-day, and 1-year case fatality rates in Matão, Brazil: a population-based prospective study

BACKGROUND AND PURPOSE

Stroke is the main cause of death in Brazil and no prospective population-based study has been conducted in the country. The purpose of this study was to determine the incidence of stroke, stroke subtypes, case fatality, and prognosis after 1 year of follow-up in the city of Matão, Brazil.

METHODS

Using overlapping methods of case ascertainment, all stroke cases that occurred in the city of Matão (population, 75,053) from November 1, 2003 to October 31, 2004 were followed-up at 1 month and 1 year after the episode. Standard criteria for population-based stroke studies were followed.

RESULTS

Of 141 suspect stroke cases identified, 81 were first-ever-in-a-lifetime strokes. All patients underwent a CT scan. The crude annual incidence rate per 100,000 per year was 108 (95% CI, 85.7-134.1) and the rate adjusted for sex and age to the Segi population was 137 (95% CI, 112.0 to 166.4) per 100,000 inhabitants per year. Ischemic stroke occurred in 69 (85.2%) subjects, intracerebral hemorrhage in 11 (13.6%), and subarachnoid hemorrhage in 1 (1.2%). The 30-day case fatality rate was 18.5 and the 1-year case fatality rate was 30.9%. After 1 year of follow-up, 43% of the patients were independent in activities of daily living, 49.4% had independent gait, and 15.9% had a recurrent stroke.

CONCLUSIONS

The present results are similar to those obtained in other stroke population-based studies. Future studies in Matão will provide the opportunity to discover ways to decrease the stroke burden in Brazil.

Trends in the incidence of subarachnoid hemorrhage in Akita Prefecture, Japan

Object

The incidence of subarachnoid hemorrhage (SAH) in Japan has been reported to be among the highest in the world. The aim of this study was to analyze the incidence of SAH and its trends in Akita Prefecture, Japan.

Methods

The incidence rate of SAH between January 1, 1989, and December 31, 1998, was investigated using the prospective Akita Stroke Register. Computed tomography scans were obtained in all suspected cases of SAH. During the study period, 3257 patients with their first SAH were registered. The crude annual incidence rates of SAH in men, women, and both sexes were 20, 33, and 27 per 100,000 population per year, respectively. Age-standardized incidence rates remained stable. Crude incidence rates in women increased. In men the incidence reached a plateau after 55 years of age; in women it peaked in the eighth decade of life. The 28-day case fatality rate was 26.7%, without significant changes. Two diurnal peaks were observed: one at 7 a.m. and another at 5 p.m. The incidence was lowest in summer and highest in spring, in both sexes.

Conclusions

The incidence of SAH in patients in Akita Prefecture is similar to that reported in other Japanese studies. The age-standardized incidence rates are stable. The increasing crude incidence in women is probably attributable to the aging of the Japanese population.

A prospective community-based study of stroke in Kolkata, India

BACKGROUND AND PURPOSE

Information on essential stroke parameters are lacking in India. This population-based study on stroke disorder was undertaken in the city of Kolkata, India, to determine the subtypes, prevalence, incidence, and case fatality rates of stroke.

METHODS

This was a longitudinal descriptive study comprising 2-stage door-to-door survey of a stratified randomly selected sample of the city population, conducted twice per year for 2 successive years from March 2003 to February 2005.

RESULTS

Out of the screened population of 52,377 (27 626 men, 24 751 women), the age standardized prevalence rate of stroke to world standard population is 545.10 (95% CI, 479.86 to 617.05) per 100,000 persons. The age standardized average annual incidence rate to world standard population of first-ever-in-a-lifetime stroke is 145.30 (95% CI, 120.39 to 174.74) per 100,000 persons per year. Thirty-day case fatality rate is 41.08% (95% CI, 30.66 to 53.80). Women have higher incidence and case fatality rates. Despite divergence on socioeconomic status between the slum and nonslum dwellers, stroke parameters were not significantly different.

CONCLUSIONS

The age standardized prevalence and incidence rates of stroke in this study are similar to or higher than many Western nations. The overall case fatality rate is among the highest category of stroke fatality in the world. The women have higher incidence and case fatality rates compared with men.