Increasing incidence of stroke among Swedish women

Worldwide Incidence of Aneurysmal Subarachnoid Hemorrhage According to Region, Time Period, Blood Pressure, and Smoking Prevalence in the Population: A Systematic Review and Meta-analysis

Importance

Subarachnoid hemorrhage (SAH) from ruptured intracranial aneurysms is a subset of stroke with high fatality and morbidity. Better understanding of a change in incidence over time and of factors associated with this change could facilitate primary prevention.

Objective

To assess worldwide SAH incidence according to region, age, sex, time period, blood pressure, and smoking prevalence.

Data Sources

We searched PubMed, Web of Science, and Embase for studies on SAH incidence published between January 1960 and March 2017. Worldwide blood pressure and smoking prevalence data were extracted from the Noncommunicable Disease Risk Factor and Global Burden of Disease data sets.

Study Selection

Population-based studies with prospective designs representative of the entire study population according to predefined criteria.

Data Extraction and Synthesis

Two reviewers independently extracted data according to PRISMA guidelines. Incidence of SAH was calculated per 100 000 person-years, and risk ratios (RRs) including 95% CIs were calculated with multivariable random-effects binomial regression. The association of SAH incidence with blood pressure and smoking prevalence was assessed with linear regression.

Main Outcomes and Measures

Incidence of SAH.

Results

A total of 75 studies from 32 countries were included. These studies comprised 8176 patients with SAH were studied over 67 746 051 person-years. Overall crude SAH incidence across all midyears was 7.9 (95% CI, 6.9-9.0) per 100 000 person-years; the RR for women was 1.3 (95% CI, 0.98-1.7). Compared with men aged 45 to 54 years, the RR in Japanese women older than 75 years was 2.5 (95% CI, 1.8-3.4) and in European women older than 75 years was 1.5 (95% CI, 0.9-2.5). Global SAH incidence declined from 10.2 (95% CI, 8.4-12.5) per 100 000 person-years in 1980 to 6.1 (95% CI, 4.9-7.5) in 2010 or by 1.7% (95% CI, 0.6-2.8) annually between 1955 and 2014. Incidence of SAH declined between 1980 and 2010 by 40.6% in Europe, 46.2% in Asia, and 14.0% in North America and increased by 59.1% in Japan. The global SAH incidence declined with every millimeter of mercury decrease in systolic blood pressure by 7.1% (95% CI, 5.8-8.4) and with every percentage decrease in smoking prevalence by 2.4% (95% CI, 1.6-3.3).

Conclusions and Relevance

Worldwide SAH incidence and its decline show large regional differences and parallel the decrease in blood pressure and smoking prevalence. Understanding determinants for regional differences and further reducing blood pressure and smoking prevalence may yield a diminished SAH burden.

Transient ischemic attack: Incidence and early risk of stroke in northern Portugal from 1998–2000 to 2009–2011

Objective

A decline in TIA incidence would be expected mirroring stroke trends, but patient's awareness of symptoms/signs, improved diagnostic procedures and changes in severity of vascular disease may raise TIA incidence. We aimed to estimate changes in TIA incidence and 30-day stroke risk in Portugal.

Methods

Data from two prospective community-based registers of first-ever TIA in 104,700 (1998–2000) and 118,232 (2009–2011) persons were collected using comprehensive case ascertainment methods. Incidence and stroke risk from TIA onset were compared using different inception cohorts. ABCD2 was used to stratified stroke risk.

Results

Overall, 141 patients were included in 1998–2000 and 174 in 2009–2011. Crude annual incidence rate increased from 67 to 74/100,000 (IRR=1.12; 95% CI, 0.90–1.40), particularly in men under 65 years (IRR=1.79; 95% CI, 1.06–3.04). Male/female IRR increased from 1.20 (0.86–1.68) in 1998–2000 to 1.77 (1.31–2.39) in 2009–2011, after adjustment for age. Better control of vascular risk factors (VRFs) accounted for lower ABCD2 scores in 2009–2011. The 30-day stroke risk was similar in study periods (18.4% vs. 16.7%, p > 0.7), decreasing from 16.1% to 8.2% ( p < 0.042) excluding patients reporting TIA after stroke occurrence and from 12.2% to 4.0% ( p < 0.011) further excluding patients who had stroke in ambulance/hospital. ABCD2 discriminated stroke risk only in 1998–2000; stroke severity decreased while posterior circulation stroke was more common in 2009–2011.

Conclusion

Despite a stable TIA incidence across periods, the risk increased in men compared to women. Better control of VRF accounted for lower ABCD2 scores and secondary prevention reduced stroke risk. Men under 65 years emerge as a preferential target for primary and secondary prevention.

Increased incidence of subarachnoid hemorrhage during cold temperatures and influenza epidemics

OBJECTIVE

This study investigated whether the increased incidence of aneurysmal subarachnoid hemorrhage (SAH) in winter is related to temperature or increased incidence of influenza. Such relationships may elucidate the pathogenesis of intracranial aneurysm rupture.

METHODS

A nationwide sample of 18,714 patients with SAH was linked with weekly temperature and influenza-like illness consultation data. Poisson regression analyses were used to calculate incidence density ratios (IDRs) with corresponding 95% CIs for the association of SAH incidence with temperature and influenza epidemics; IDRs were adjusted for study year (aIDR). In addition, SAH incidence data from 30 European population-based studies were linked with daily temperature data from the European Climate Assessment.

RESULTS

The aIDR for SAH during influenza epidemics was 1.061 (95% CI 1.022–1.101) in the univariable and 1.030 (95% CI 0.989–1.074) in the multivariable analysis. This association declined gradually during the weeks after epidemics. Per 1°C temperature drop, the aIDR was 1.005 (95% CI 1.003–1.008) in the univariable and 1.004 (95% CI 1.002–1.007) in the multivariable analysis. In the European population-based studies, the IDR was 1.143 (95% CI 1.129–1.157) per 1°C temperature drop.

CONCLUSIONS

The incidence of SAH is increased during cold temperatures and epidemic influenza. Future studies with individual patient data are needed to investigate causality between temperature or influenza and SAH.

National registry-based case-control study: comorbidity and stroke in young adults

OBJECTIVES

Stroke is overrepresented in cohorts of young adults with chronic diseases. The prevalence and impact of comorbidity among young stroke patients have not been compared with individuals without stroke. Our aim was to investigate the association between comorbidity and stroke in young adults.

MATERIALS AND METHODS

A nationwide cohort of patients (aged 15-44 years), registered in the Swedish Stroke Register, (Riksstroke) 2001-2009, was identified. Age- and sex-matched controls were randomly selected from the Population Register of Sweden. Discharge diagnoses were retrieved from the National Patient Register and grouped by chapter in the International Classification of Diseases 10th revision. Associations between ICD-10 chapters and stroke were stratified (age, sex, and stroke type) and analyzed by multivariable logistic regression.

RESULTS

In 2599 stroke patients analyzed, the prevalence of vascular risk factors (hypertension 25.3%, dyslipidemia 13.0%, diabetes 9.7%, heart failure 3.2%, and atrial fibrillation 2.8%), all ICD-10 chapters (except pregnancy) and prestroke hospitalizations were more frequent among cases than controls. Independent associations were found between stroke and eight ICD-10 chapters: neoplasms (odds ratios (OR) 1.53, 95% CI 1.15-2.05), blood (OR 1.61, 1.11-2.34), endocrine (OR 2.28, 1.77-2.93), psychiatric (OR 1.50, 1.24-1.81), nervous (OR 1.91, 1.46-2.50), eye (OR 1.67, 1.05-2.64), circulatory (OR 3.05, 2.45-3.80), and symptoms (OR 1.31, 1.13-1.52). The risk of stroke increased by 26% per ICD-10 chapter diagnosed.

CONCLUSIONS

In addition to vascular risk factors, comorbidity (represented by ICD-10 chapters) was associated with increased risk of stroke in young individuals. The risk of stroke was further increased with the number of diagnosed ICD-10 chapters.

Environmental factors and stroke: A selective review

Despite numerous prior stroke risk factor investigations, much remains unknown about the effect of environmental factor changes on stroke incidence and mortality rates. Yet these data might be important for defining a number of measures to prevent stroke and for developing a greater understanding of the origin and incidence trends of stroke in different regions and populations. In this paper we review the current state of knowledge about certain environmental stroke risk factors.

Risks and Benefits of Thrombolysis in the Elderly

Background and purpose

Stroke incidence continues to rise exponentially with age even as temporal trends in some population risk factors increase and others decline. In general, older patients with stroke have worse outcomes compared to their younger counterparts. Stroke severity, concurrent medical problems, prestroke disability, and less-aggressive acute and chronic management are a few contributing factors to account for this poor prognosis. Acute thrombolysis therapy is the only proven treatment in acute ischemic stroke. However, elderly patients have mostly been excluded from acute revascularization studies, due predominantly to their overall poor prognosis and the fear of hemorrhagic complications from these treatments. Despite this, there is no evidence to suggest that the risk benefit ratio of thrombolysis treatment is substantially different in the elderly than in younger ischemic stroke patients.

Summary of review

In this review, we briefly examine the stroke risk factor profile and outcome in the elderly and review the current evidence regarding intravenous and intra-arterial revascularization treatments.

Conclusion

We feel that carefully selected patients who meet eligibility criteria for thrombolysis should not be denied this therapy on the basis of age alone.

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.

Prevalence of disabling spasticity 1 year after first-ever stroke

OBJECTIVE

To estimate the prevalence of disabling spasticity (DS) 1 year after first-ever stroke.

DESIGN

Cross-sectional survey 1 year after first-ever stroke.

METHODS

Patients above 18 years from one county with first-ever stroke were identified by use of the national stroke registry. A representative sample of 163 patients was created and 140 of these were followed up. Assessments of motor function and ability with the modified Ashworth Scale, the modified Rankin Scale (mRS), the Barthel Index (BI) and clinical evaluation were performed in order to identify patients with spasticity-related disability.

RESULTS

The observed prevalence of any spasticity was 17% and of DS 4%. Patients with DS scored significantly worse than those with no DS on the mRS (P = 0.009) and the BI (P = 0.005). DS was more frequent in the upper extremity, correlated positively with other indices of motor impairment and inversely with age. There was an independent effect of severe upper extremity paresis (OR 22, CI 3.9-125) and age below 65 years (OR 9.5, CI 1.5-60).

CONCLUSIONS

The prevalence of DS after first-ever stroke is low but corresponds to a large number of patients and deserves further attention with regards to prevention and treatment.

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.

Change in stroke incidence, mortality, case-fatality, severity, and risk factors in Oxfordshire, UK from 1981 to 2004 (Oxford Vascular Study)

BACKGROUND

The incidence of stroke is predicted to rise because of the rapidly ageing population. However, over the past two decades, findings of randomised trials have identified several interventions that are effective in prevention of stroke. Reliable data on time-trends in stroke incidence, major risk factors, and use of preventive treatments in an ageing population are required to ascertain whether implementation of preventive strategies can offset the predicted rise in stroke incidence. We aimed to obtain these data.

METHODS

We ascertained changes in incidence of transient ischaemic attack and stroke, risk factors, and premorbid use of preventive treatments from 1981-84 (Oxford Community Stroke Project; OCSP) to 2002-04 (Oxford Vascular Study; OXVASC).

FINDINGS

Of 476 patients with transient ischaemic attacks or strokes in OXVASC, 262 strokes and 93 transient ischaemic attacks were incident events. Despite more complete case-ascertainment than in OCSP, age-adjusted and sex-adjusted incidence of first-ever stroke fell by 29% (relative incidence 0.71, 95% CI 0.61-0.83, p=0.0002). Incidence declined by more than 50% for primary intracerebral haemorrhage (0.47, 0.27-0.83, p=0.01) but was unchanged for subarachnoid haemorrhage (0.83, 0.44-1.57, p=0.57). Thus, although 28% more incident strokes (366 vs 286) were expected in OXVASC due to demographic change alone (33% increase in those aged 75 or older), the observed number fell (262 vs 286). Major reductions were recorded in mortality rates for incident stroke (0.63, 0.44-0.90, p=0.02) and in incidence of disabling or fatal stroke (0.60, 0.50-0.73, p<0.0001), but no change was seen in case-fatality due to incident stroke (17.2% vs 17.8%; age and sex adjusted relative risk 0.85, 95% CI 0.57-1.28, p=0.45). Comparison of premorbid risk factors revealed substantial reductions in the proportion of smokers, mean total cholesterol, and mean systolic and diastolic blood pressures and major increases in premorbid treatment with antiplatelet, lipid-lowering, and blood pressure lowering drugs (all p<0.0001).

INTERPRETATION

The age-specific incidence of major stroke in Oxfordshire has fallen by 40% over the past 20 years in association with increased use of preventive treatments and major reductions in premorbid risk factors.

Secular trends in mortality by stroke subtype in the 20th century: a retrospective analysis

BACKGROUND

Since both cerebral infarction and coronary heart disease are caused by atherosclerosis, they would be expected to have similar secular trends in mortality. Because differential diagnosis of stroke subtype on routine death certificates is inaccurate, we aimed to estimate secular trends in cerebral infarct and haemorrhage throughout the 20th century, for England and Wales, with data from autopsy studies.

METHODS

We calculated the ratio of cerebral infarct to cerebral haemorrhage from all available sources of autopsy data from the 20th century. These data were used to estimate the ratio of cerebral infarct to haemorrhage for every year, and hence to estimate rates of cerebral infarct and cerebral haemorrhage from the total stroke mortality rate, obtained from the UK Office for National Statistics.

FINDINGS

Data about stroke subtypes from autopsies were available from 1932 to 1999. The ratio of cerebral infarct to cerebral haemorrhage increased fourfold from 0.5 in the 1930s to 2.0 by the 1990s; most of the increase took place between the 1930s and the 1970s. Estimated secular trends suggested that there was a steady fall in mortality from cerebral haemorrhage throughout the 20th century, whereas mortality from cerebral infarct increased to a peak in the 1970s and then fell. Trends in estimated cerebral infarct mortality closely matched those for coronary heart disease mortality.

INTERPRETATION

The closely related trends in cerebral infarct and coronary heart disease suggest common causes, but the very different trend in cerebral haemorrhage shows that its cause probably differs importantly from these conditions.

Long term cost-of-illness in stroke: an international review

An international review of the costs of stroke was conducted to explore data sources, and cost variables as well as to compare estimates of the annual aggregated cost (prevalence-based) and total per patient long-term cost (incidence-based) of care. Dutch, English, French, German, Italian and Spanish literature was searched using the keywords stroke, ischaemic stroke, haemorrhagic stroke, cerebrovascular accident, cerebral infarction, cost(s), economics, and cost analysis. Criteria for study inclusion were: provides estimates of direct and/or indirect costs of stroke, published after 1989, methods described in adequate detail, and for studies of long-term costs, estimates based on a minimum 5 years of care following the event. Cost estimates are presented in original currencies and US dollars. Among studies representing Australia, New Zealand, Western Europe and North America, six prevalence studies reported total annual aggregated costs of US dollars 7,975 (1988 values) to US dollars 54,546 (1993 values) per patient; eight incidence-based studies reported total long-term per patient costs of US dollars 18,538 (1991 values) to US dollars 228,038 (1990 values). Identifiable factors underlying variation included: perspective employed, cost variables considered, and exclusion of comorbidities. Although lack of uniformity hampers inter-study comparisons, it is evident that stroke poses a significant economic burden. Consensus on standard cost variables and methods for projections of resource use and survival over time are clearly warranted.

Aphasia in acute stroke and relation to outcome

OBJECTIVES

The natural course of aphasia in unselected, consecutive stroke patients is not well established. We investigated morbidity, mortality and recovery for different types of aphasia in consecutive unselected aphasic patients with acute stroke. Setting and subjects. In 119 aphasic patients, the type and degree of aphasia were assessed acutely and at 3, 6 and 18 months after stroke onset, using Reinvang's 'Grunntest for afasi' and Amsterdam-Nijmegen-Everyday-Language-Test.

RESULTS

About one-third of patients with acute stroke had presented with aphasia. Mortality among the aphasic patients during the 18-month follow-up was twice that in non-aphasics (36 vs. 16%). Presence of atrial fibrillation was associated with poorer prognosis. At 18 months, 24% of the 119 aphasic patients had recovered completely, 43% still had significant aphasia, and 21% had died. The proportion with global aphasia decreased from almost 25% acutely to a few per cent after 18 months, that with Wernicke's aphasia from 25% to less than 10%, whereas conduction aphasia increased from 13 to 23% during follow-up. Among those with initial mild aphasia, 70% recovered completely. Great improvement was observed in patients with initial low degree of speech function. Younger patients recovered to a greater extent than older patients.

CONCLUSION

The high long-term mortality among aphasics may be seen as an indirect sign of advanced cardiovascular disease. A combination of different and adjusted aphasia tests provided the possibility to assess almost all acute aphasic patients. Irrespective of type and degree of aphasia, great improvements were seen in almost all aphasic patients. Even patients with severe speech impairment have a considerable potential for recovery, particularly in the first 3 months after stroke.

Primary intracerebral and aneurysmal subarachnoid hemorrhage in Izumo City, Japan. Part I: incidence and seasonal and diurnal variations

OBJECT

The purpose of this community-based study was first to estimate the incidence rates of primary intracerebral hemorrhage (ICH) and aneurysmal subarachnoid hemorrhage (SAH) in Izumo City, Japan, and second to investigate whether there were seasonal and diurnal periodicities in their onset.

METHODS

During 1991 through 1996, 267 patients with primary ICH and 123 with aneurysmal SAH were treated in Izumo City. The crude and the age- and sex-adjusted annual incidence rates per 100,000 population for all ages were 52 and 48 for ICH and 24 and 23 for SAH, respectively. These incidence rates were higher than those previously published for any other geographical region. The incidence rates of both ICH and SAH increased almost linearly with age. For ICH, a significant seasonal pattern was observed in men and in patients younger than 65 years, with a peak in winter and a trough in summer. However, no significant seasonal fluctuation was found in women or in individuals aged 65 years or older. There was no significant seasonal periodicity for SAH, even when patients were analyzed according to sex and age. Diurnal variations in the onset of both ICH and SAH were significant (except in men with SAH), with a nadir between midnight and 6:00 a.m.

CONCLUSIONS

The actual incidence rates of both primary ICH and aneurysmal SAH seem to be much higher than have been reported so far. In addition, the data indicate the existence of seasonal periodicity for men and younger patients with ICH, and that the risk of both ICH and SAH is lower during nighttime.

Etiology and pathophysiology of stroke as a complex trait

Stroke (brain attack) is currently the third leading cause of death in Western societies. Recent advances in molecular genetics have finally demonstrated what has long been suggested by the clinical observation, that is, stroke is not only the complication of major pathologic conditions such as atherosclerosis, hypertension, or cardiac diseases, but rather it represents a complex trait itself. Thus, the pathogenesis of stroke is often the result of the combined effects of genes exerting a direct contributory role and of their interactions with several environmental determinants. A genetic dissection of stroke has been attempted in suitable animal models and in humans. With this approach, the genetic defects underlying monogenic disorders associated with stroke were identified. Moreover, important findings have recently highlighted the contribution of genes encoding cardiovascular hormones, such as the atrial natriuretic peptide, for the pathogenesis of multifactorial, polygenic forms of stroke. A more thorough understanding of the fine mechanisms, dependent from mutations within stroke susceptibility genes and underlying the disease pathogenesis, may help to introduce new specific tools to achieve better prevention and treatment of stroke.

Stroke: epidemiology, clinical picture, and risk factors--Part I of III

The aim of this review is to present the current knowledge regarding stroke. It will appear in three parts (in part II the pathogenesis, investigations, and prognosis will be presented, while part III will consist of the management and rehabilitation). In the current part (I) the definitions of the clinical picture are presented. These include: amaurosis fugax, vertebrobasilar transient ischemic attack, and stroke (with good recovery, in evolution and complete). The role of the following risk factors is discussed in detail: age, gender, ethnicity, heredity, hypertension, cigarette smoking, hyperlipidemia, diabetes mellitus, obesity, fibrinogen and clotting factors, oral contraceptives, erythrocytosis and hematocrit level, prior cerebrovascular and other diseases, physical inactivity, diet and alcohol consumption, illicit drug use, and genetic predisposition. In particular, regarding the carotid arteries, the following characteristics are analyzed: atheroma, carotid plaque echomorphology, carotid stenosis, presence of ulcer, local variations in surface deformability, pathological characteristics, and dissection. Finally the significance of the cerebral collateral circulation and the conditions predisposing to cardioembolism and to cerebral hemorrhage are presented.

Intracerebral haemorrhages and oral anticoagulation in the north of Scotland

The aim of this study has been twofold: 1--to examine the impact of oral anticoagulant (OAC) use on a possible recent rise in the admission rate of intracerebral haemorrhages to Aberdeen Royal Infirmary (ARI), and 2--to estimate the absolute risk of intracranial haemorrhage for outpatients followed up in the OAC Clinic at ARI. The number of patients admitted to ARI with intracerebral bleedings increased by 60% between 1993 and 1998. A corresponding increase in the proportion of patients with concurrent OAC use (4.7% vs 15.7%, p = 0.055) cannot sufficiently explain the increase in the total number of intracerebral haemorrhages. The average annual incidence of intracranial haemorrhages for the OAC Clinic at ARI is found to be acceptably low at 0.33% per year. Further audit of the large number of patients receiving warfarin outwith the supervision of the clinic is urgently required.

Intracerebral hemorrhage

Intracerebral hemorrhage (ICH) represents a significant fraction of all strokes and causes a disproportionate amount of stroke related morbidity and mortality, especially in young blacks. While diagnosis of this disorder has greatly improved in the CT era, morbidity and mortality remain essentially unchanged. Not one currently utilized therapeutic modality has been clearly associated with a beneficial effect on long term outcome in small prospective randomized treatment trials for ICH. In spite of the lack of scientific data regarding therapy, patients often require aggressive medical and surgical intervention because of the life-threatening presentation of many patients. Recent clinical and experimental ICH research has identified a number of potentially effective new therapeutic strategies, and time to treatment is likely to be very important as it is for ischemic stroke. Large prospective, randomized, placebo controlled trials to examine the judicious application of current therapeutic modalities, and to investigate the potential benefit of proposed new treatment modalities, are long overdue.

Increasing hospital admission rates for intracerebral hemorrhage during the last decade

BACKGROUND

The incidence and mortality of all types of strokes, including intracerebral hemorrhages, declined during the 1970s. However, some evidence exists that these trends stabilized or reversed during the 1980s. In the present study, a large North American population was observed from 1981 to 1989 to assess changes in the annual hospital admission rates of intracerebral hemorrhage.

METHOD

Data provided by the Connecticut Health Information Management and Exchange (CHIME, Wallingford, Connecticut), a state-wide clinical database of records submitted voluntarily by all of Connecticut's 36 acute care, nongovernment hospitals, was analyzed for all patients with primary diagnosis of intracerebral hemorrhage (ICD-9-CM=431) for the fiscal years 1981, 1983, 1985, 1987, 1988, and 1989.

RESULTS

During the time periods studied, there were 3,277 hospitalizations with a primary diagnosis of intracerebral hemorrhage. There was an initial annual hospital admission rate of 12 per 100,000 in 1981. Rates steadily increased to nearly 20 per 10,000 in 1988 and 1989. This increase in hospital admission rates from intracerebral hemorrhage was statistically significant when the data were adjusted for gender, race, and age (P<.001). When admission rates for intracerebral hemorrhage were stratified by age, admission rates increased dramatically only in those 65 years and older (P<.001). The in-hospital death rate decreased during the study decade (P=.004); however, age-adjusted analysis indicated that in-hospital deaths increased significantly (P<.001) in patients 65 years and older.

CONCLUSIONS

Hospital admission rates for intracerebral hemorrhage nearly doubled from 1981 to 1989. This change may be due to an actual increase in the annual incidence of intracerebral hemorrhage caused by mechanisms that are not yet fully understood.

Decreasing incidence of stroke in central Finland, 1985-1993

INTRODUCTION

During the last decades the age-standardized stroke mortality has declined in Finland as in many other industrialized countries. Epidemiological studies have, however, not been consistent in explaining this fall in mortality. Our aim was to shed light on this question by using two consecutive, population-based surveys.

PATIENTS & METHODS

The target of the two one-year surveys was the population living in the Jyväskylä Region of central Finland, and the surveys were performed in 1985-86 (population 114,669) and 1993 (population 123,547). The case finding methods and the diagnostic criteria were identical in both studies. All hospital records and autopsy reports of patients with ICD (8th and 9th revision) codes 430-438 were collected and perused. Patients with first-ever stroke were included in the study.

RESULTS

The number of patients with first-ever stroke in the 1985-86 and 1993 surveys were 219 and 189, respectively, and 92% of them were treated at the Department of Neurology. The age-standardized (European standard population > or = 25 years) annual total stroke incidence showed a statistically significant decline over these 8 years from 317 (95% confidence interval 274-360) to 227 (95% confidence interval 194-260) per 100,000. In both studies the survival was similar with 79% of the patients surviving at 28 days after stroke onset, and 65-69% at 1 year. Recurrent strokes, 52 in 1985-86 and 50 in 1993 also showed a declining trend and no changes in survival were observed.

CONCLUSIONS

The decline in stroke mortality in Finland is best explained by the declining incidence of stroke. In the present study we did not find changes in the 1st year survival after stroke onset.

The epidemiology of hypertension control in populations

Despite an aging population, prevalence rates for hypertension in the U.S. remain stable due to a decrease in rates in women but a corresponding increase in rates for men. Epidemiological factors which may contribute to these rates are discussed. The lack of a threshold for the association between blood pressure and disease events means that the majority of events occur in the larger number of people with mild disease. Because the efficacy and cost-effectiveness of medical therapy to lower mildly elevated blood pressure remains controversial, population-based strategies to effect behavior change are the most prudent course for this, the largest group at risk. Targeted, resource-intensive medical intervention for those at high risk combined with hygienic measures for the population with mildly elevated blood pressure from the basis for an effective public health strategy.

Assessment of rehabilitation technologies in stroke. Outcomes and costs

Initial functional ability (Barthel Index, mean 57) was found to be an important predictor of functional ability 1 year after stroke (mean 80) and for costs during the period. On average the total cost for a stroke patient was about SEK 200,000; the main expense, accommodation, averaged about SEK 140,000, while assistive devices amounted to SEK 2,600. Those who use assistive devices, although having achieved a high functional ability, perceive and rate their life situation (Nottingham Health Profile) considerably more impaired than those without assistive devices.

Costs of stroke in Sweden. A national perspective

BACKGROUND AND PURPOSE

Cost-effectiveness analyses of stroke management are hampered by paucity of economic data. We made an update of the direct and indirect costs of stroke in Sweden (population, 8.5 million).

METHODS

Direct costs (ie, the costs for hospital and outpatient care and social services) were estimated on the basis of two prospective population-based studies of stroke and of two nationwide cross-sectional inventories of bed-days and diagnoses. Indirect costs (ie, the costs for loss of productivity and early retirement) were based on official statistics.

RESULTS

The direct annual costs of care for stroke patients in 1991 equaled 7836 million Swedish krona (SKr) ($1306 million in US dollars), and the indirect costs, 2430 million SKr ($405 million). The cost of stroke care was 1208 SKr ($201) per inhabitant in Sweden. The expected direct costs per patient from first stroke to death were 440,000 SKr ($73,333). When prestroke costs for other diseases and advanced age were subtracted, the sum was reduced to 180,000 SKr ($30,000).

CONCLUSIONS

Costs for hospital and outpatient care and social services accounted for 76% of Swedish stroke costs and for 24% of costs for loss of production and early retirement. Only 41% of direct costs were stroke-related.

Declining trends in incidence, case-fatality and mortality of stroke in three geographic areas of Finland during 1983-1989. Results from the FINMONICA stroke register

Stroke mortality has decreased during the last decade in many industrialized countries, but there has been no clear evidence for a decline in the incidence of stroke. The present study analyzes the trends in the incidence, mortality and case-fatality of stroke in Finland from 1983 to 1989. We used data from the FINMONICA stroke register, a community based register collecting information on all suspected stroke cases aged 25-74 in three geographical areas of Finland. Annual attack rate, incidence, mortality and case-fatality rates were calculated for all strokes and for different subcategories of stroke. A linear regression model was applied to calculate the yearly trends of these rates. In men, the attack rate of stroke was 336/100,000 in 1983 and 310/100,000 in 1989 (-8% during the observation period); incidence declined from 269/100,000 in 1983 to 236/100,000 in 1989 (-12%); mortality declined from 82/100,000 to 64/100,000 (-22%), and case-fatality declined from 25% to 21% (-18%). Also among women similar declining trends were observed (-11%, -13%, -16%, and -10% respectively), but they were not statistically significant. In both incidence and mortality of stroke, the decline was seen in all age groups. Incidence and mortality of cerebral infarction declined similarly to all strokes. A large fall in the incidence (-24% in both men and women) and mortality (-38% in men and -27% in women) of subarachnoid haemorrhage was also observed. An increasing trend, although not significant, was instead observed for cerebral haemorrhage. First stroke and especially first cerebral infarction contributed most to the decline in case-fatality. The availability of computerized brain tomography improved from 18% in 1983 to 60% in 1989. We observed a fall in the incidence, mortality, and case-fatality of stroke during 1983-1989. Among the subtypes of stroke, cerebral infarction contributed most to the decline, but the data suggested also a declining trend in the incidence and mortality of subarachnoid haemorrhage, observed now for the first time in Finland since the 1960s. The fall in the incidence of stroke was not as steep during the 1980s as it was during the 1970s; Finland is anyhow the only European country which has reported a decreasing trend in stroke incidence during the 1980s. We need now to investigate how much the decline in the classical risk factors for stroke observed in Finland during the last two decades predicts the observed trends.

Trends in incidence, case-fatality rate, and severity of stroke in northern Sweden, 1985-1991

BACKGROUND AND PURPOSE--Incidence, case-fatality rate at 28 days, and severity of acute stroke were recorded for 7 years in a large population-based stroke register to understand the reasons for the decline in stroke mortality in northern Sweden.

METHODS

Within the framework of the World Health Organization MONICA Project, acute stroke was monitored in people aged 35 to 74 years in northern Sweden from 1985 through 1991 (target population in 1985, 238,948).

RESULTS

The annual incidence of stroke decreased by an average of 2.3%/y in men aged 35 to 64 years (P = .074) and increased significantly by 1.1%/y in men aged 65 to 74 years (P = .041). No significant changes in incidence occurred in either age group in women. The 28-day case-fatality rate in first-ever strokes (both sexes together) declined from 21.9% to 15.4% in patients aged 65 to 74 years (P = .02). Among survivors, the proportion with extensive motor deficits (at any time during the first 28 days) declined in patients younger than 65 years as well as in those older than 65 years (P = .007 and P = .019, respectively). In patients aged 35 to 64 years, the proportion with aphasia/dysphasia also decreased significantly (P = .032), but no such trend was seen in those aged 65 to 74 years.

CONCLUSIONS

A shift toward higher ages has been noted in the occurrence of first-ever strokes in men, while incidence has remained unchanged in women. During the 7 years of observation, stroke has become a less severe disease.

Stroke incidence and mortality in rural and urban Shanghai from 1984 through 1991. Findings from a community-based registry

BACKGROUND

Mortality from stroke has declined in many countries. This decline may result from a fall in incidence of stroke or a decrease in case fatality from stroke. The present study was conducted to investigate the temporal trends of incidence rate, mortality rate, and case fatality of stroke in an urban and rural Chinese population.

METHODS

A community-based registry study was established in 1983 in defined rural and urban areas of Shanghai with a population aged 35 to 74 years of approximately 86,000 subjects, adhering to the methods and definitions of the World Health Organization MONICA protocol. All stroke events occurring in the population aged 35 to 74 years in these areas were registered by a special three-level case-registration system.

RESULTS

From 1984 through 1991, 1391 stroke cases were identified. No significant change in the incidence rate of stroke was observed from 1984 through 1991 in men and women living in rural and urban areas. Age-standardized mortality rates (per 100,000 person years) of stroke declined significantly during this period, except for rural women. The annual changes and 95% confidence intervals of age-standardized mortality rates were: for rural men -4.6% (-5.4, -3.9), for rural women -0.6% (-1.6, 0.5), for urban men -2.5% (-3.5, -1.6), and for urban women -4.7% (-5.2, -4.2). A significant decrease in case fatality from stroke from 1984 through 1991 was found among men living in rural areas (from 62.4% to 46.0%) and among women living in urban areas (from 48.4% to 33.3%). Overall case fatality, however, showed a nonsignificant decline over time.

CONCLUSIONS

We observed a decline in stroke mortality rate in a rural and urban Chinese population. No significant changes in stroke incidence were found in this study, whereas case fatality appeared to have decreased, in particular among men living in rural areas and women living in urban areas.

Changes in stroke incidence and case-fatality in Auckland, New Zealand, 1981-91

The explanation for the substantial decline in stroke death rates can be investigated only by measuring trends in stroke incidence and case-fatality. Two community-based studies carried out in Auckland, New Zealand, in 1981 and 1991 used comparable methods and definitions, met criteria for well-designed studies, and had the power to detect small changes in incidence and case-fatality rates. 703 events (representing 50% of all strokes) were registered in 1981 and 1735 events in 1991. 521 (74.1%) and 1255 (72.3%) events in 1981 and 1991, respectively, were first-ever (in a lifetime) strokes. Although there was no change in overall stroke incidence between 1981 and 1991, there were changes in age and sex groups. The incidence rate among women younger than 75 years rose by a fifth (rate ratio 1.23 [95% CI 1.04-1.47]), whereas that in men of 75 years and older fell by a third (rate ratio 0.67 [0.54-0.82]). The 28-day case-fatality declined from 27.1 (21.7-32.6)% to 21.9 (18.1-25.7)% in men and from 37.6 (31.8-43.5)% to 25.8 (22.3-29.4)% in women from 1981 to 1991, but the decline was not statistically significant in any age or sex group. These findings suggest that we need to reappraise strategies for the prevention of stroke and assess the implications of improved survival in elderly stroke patients.

Stroke incidence with hypertension and ischemic heart disease in Rochester, Minnesota

The primary contribution to increased incidence rates for ischemic stroke in Rochester, Minnesota, for the 1980 to 1984 time period in the age groups from 55 to 84 years was from those persons in the population with ischemic heart disease. The rate and pattern of the decline in incidence rates of ischemic stroke in hypertensive individuals and in nonhypertensive individuals were quite similar, showing no demonstrable population effect of antihypertensive medication. These observations emphasize that there must be some, as yet unidentified, factor that is important in the decline of stroke incidence.

Trends in stroke mortality and incidence in Finland in the 1970s and 1980s

This article presents trends in stroke mortality and incidence in Finland among people aged 25 to 74 years. Between 1971 and 1980, stroke mortality declined steeply: 4.1% per year among men and 5.5% per year among women. Between 1981 and 1991 the decline was smaller; about 2.2% per year in men and 2.8% per year in women. The North Karelia stroke register showed that stroke mortality declined in men from 155 per 100,000 per year in 1972 to 1973, to 87 per 100,000 per year in 1982 to 1983, and in women from 114 to 44 per 100,000 per year. A slight decline in mortality was observed during the 1980s in men, but not in women. The incidence of stroke also declined in North Karelia during the 1970s, from 328 to 248 per 100,000 per year in men, and from 230 to 141 per 100,000 in women. In the FINMONICA stroke register, the average rate of decline in incidence of stroke between 1983 and 1989 was 1.7% per year in men and 1.8% per year in women. Declines in incidence and mortality from subarachnoid hemorrhage were observed in both men and women; nevertheless it was the decline in cerebral infarction that accounted for most of the changes since about 80% of all strokes are cerebral infarctions. In conclusion, despite steep falls in stroke mortality and incidence in the 1970s, stroke mortality is still high in Finland compared with other nations. During the 1980s, the decline in stroke mortality was less and incidence leveled off until it resumed from 1987 to 1989.(ABSTRACT TRUNCATED AT 250 WORDS)

Stroke mortality and case-fatality rates in three geographic areas of Finland from 1983 to 1986

BACKGROUND AND PURPOSE

Our aim was to describe the mortality and early case-fatality rates of stroke in three geographic areas of Finland during 1983 to 1986 by means of a community-based stroke register and to estimate the accuracy of registration of stroke deaths in the official statistics compared with the FINMONICA stroke register.

METHODS

Annual and average mortality and case-fatality rates of stroke were derived from data collected in the FINMONICA stroke register during 1983 to 1986. Age-specific and age-standardized rates were calculated for the three areas, and the results were compared with the official mortality statistics and with the case-fatality figures published previously in the literature for Finland and elsewhere.

RESULTS

Mortality from stroke in the three FINMONICA areas was between 73 and 90 per 100,000 per year among men aged 25 to 74 years and between 42 and 55 per 100,000 per year among women in the same age group. Average case-fatality was similar in the three areas and globally high: 20% to 27% in men and 24% to 28% in women. Approximately half of the fatal strokes occurred within less than 2 days from the onset of the attack, and a further 25% within the first week. Hemorrhagic strokes accounted for 54% to 81% of all fatal strokes occurring in less than 2 days among men, while among women the corresponding proportions varied in the three areas between 35% and 74%. Of cerebral infarctions, approximately 28% to 37% among men and 19% to 20% among women were fatal within less than 2 days. Although the number of fatal strokes was similar in both the FINMONICA register and official mortality statistics, only 82% to 85% of the stroke cases were common in both registers; a further 13% to 14% of the cases classified as stroke deaths in the FINMONICA register could also be found in the official mortality statistics, but the underlying cause of death was something other than stroke.

CONCLUSIONS

The reliability of the Finnish official mortality statistics with regard to stroke deaths is reasonably good in aggregate numbers, but at the individual level considerable discrepancies seem to occur. Mortality from stroke in Finland has not declined further after 1979 and remains high internationally. Early case-fatality of stroke also seems higher in Finland than in most other countries. We believe that both the high incidence of stroke and the severity of the attacks are contributing to mortality and case-fatality rates of stroke in Finland.

Stroke care in the next decades: a projection derived from a community-based study in Umbria, Italy

Recently published data show that stroke incidence is not longer declining, while case fatality rates has had a less pronounced fall in recent years than in the past. Projections of the increasing number of elderly people, combined with the greater risk of stroke in old age, suggest that in the forthcoming decades we will be faced with an increased request of health resources for patients with stroke. We have therefore used data from a community-based study on stroke incidence and outcome to project the number of first ever strokes, death from stroke and handicap from stroke in Italy, up to the year 2016. Results show that incidence will increase by 22.2%, and death at 6 months from first ever stroke by 29%. However, since patients already handicapped for other reasons are more likely to die from their stroke, the net number of newly handicapped persons will only increased by 5%. These results suggest that in the next decades the major increase in request of health care resources will result from the acute event and the immediate post-ictal phase, and not from the management of chronic handicap after a stroke.

Intracerebral hemorrhage more than twice as common as subarachnoid hemorrhage

The authors report a study of all instances of spontaneous intracerebral hemorrhage (ICH) (188 cases) and subarachnoid hemorrhage (SAH) (80 cases) that occurred in the Greater Cincinnati area during 1988. Adjusted for age, sex, and race, the annual incidence of ICH was 15 per 100,000 population (95% confidence interval 13 to 17) versus six per 100,000 for SAH (95% confidence interval 5 to 8). The incidence of ICH was at least double that of SAH for women, men, and whites and approximately 1 1/2 times that for blacks. The 30-day mortality rate of 44% for ICH was not significantly different from the 46% mortality rate for SAH. Despite the evidence that ICH is more than twice as common and the disorder just as deadly as SAH, clinical and laboratory research continues to focus primarily on SAH.

Secular trend of mortality from cerebral infarction and cerebral hemorrhage in Taiwan, 1974-1988

BACKGROUND AND PURPOSE

Pathological patterns of stroke are different in various races, with the predominant stroke type in the Chinese being intracerebral hemorrhage. A total of 31,078 deaths from cerebral infarction and 77,773 deaths from cerebral hemorrhage in Taiwan were reported for groups of subjects aged 40-79 years during the period 1974-1988 to elucidate their secular trends.

METHODS

Vital statistics and demographic data were collected for analyzing the truncated age-adjusted mortality rates. Poisson regression analysis was used to estimate the relative risk and 95% confidence interval.

RESULTS

The mortality rates for cerebral hemorrhage were greater than those for cerebral infarction. The mortality rates increased exponentially with age for both subtypes. The decline in age-specific mortality for the period 1974-1983 was much more striking for cerebral hemorrhage than for cerebral infarction. Mortality from cerebral infarction and hemorrhage increased with age for all birth cohorts except the cerebral hemorrhage mortality of the oldest cohort. Male/female ratios for both cerebral infarction and hemorrhage were greater in the younger age groups. The cerebral hemorrhage/infarction ratio during the period 1984-1988 was highest for the younger age groups and lowest for the oldest age groups.

CONCLUSIONS

The different secular trends of mortality from cerebral infarction and hemorrhage imply that these two patterns of stroke may be associated with some different risk factors.

Determining the incidence of different subtypes of stroke: results from the Perth Community Stroke Study, 1989-1990

OBJECTIVE

To determine the incidence and case fatality of seven distinct subtypes of stroke in Perth, Western Australia.

DESIGN AND SETTING

A population-based descriptive epidemiological study.

SUBJECTS

All residents of a geographically defined segment of the Perth metropolitan area (estimated population 138,708 persons) who had a stroke or transient ischaemic attack between 20 February 1989 and 19 August 1990, inclusive.

MAIN OUTCOME MEASURES

The following subtypes of stroke were classified according to standard clinical, radiological and pathological criteria: types of cerebral infarction, namely, large artery (thrombotic) occlusive infarction (LAOI), cerebral embolic infarction (EMBI), lacunar infarction (LACI) and boundary zone infarction (BZI); primary intracerebral haemorrhage (PICH); subarachnoid haemorrhage (SAH); and stroke of undetermined cause.

RESULTS

Over the 18-month study period 536 stroke events were registered, of which 86% (95% confidence interval, 83%-89%) had a defined "pathological" diagnosis on the basis of computed tomographic scanning, magnetic resonance imaging or necropsy. Cerebral infarction accounted for 71% of cases (95% CI, 68%-75%), PICH 11% (95% CI, 9%-14%) and SAH 4% (95% CI, 2%-5%). The 382 cases of cerebral infarction included LAOI (in approximately 71%), EMBI (15%), LACI (10%) and BZI (5%). While the incidence of all subtypes of stroke increased with age, there were age and sex differences in their proportional frequency, management and prognosis: patients with PICH, SAH and EMBI were more likely to be admitted to hospital, and these conditions carried the highest early case fatality. Over all, the 28-day case fatality was 24% (95% CI, 20%-28%), but varied from 0 for LACI and BZI, to 37% (95% CI, 15%-59%) for SAH and 35% (CI, 23%-47%) for PICH.

CONCLUSIONS

In this study, we found considerable differences in incidence rates, the effect of age and sex on incidence rates, and prognosis for the different subtypes of stroke. Hospital-based studies are likely to be selectively biased by emphasising strokes that are severe and require admission to hospital. These data have important implications in the design and evaluation of clinical trials of therapy for stroke.

Ascertaining the true incidence of stroke: experience from the Perth Community Stroke Study, 1989-1990

OBJECTIVE

To determine the age and sex specific incidence, and case fatality of stroke in Perth, Western Australia.

DESIGN AND SETTING

A population-based descriptive epidemiological study.

SUBJECTS

All residents of a geographically defined segment of the Perth metropolitan area (population 138,708) who had a stroke or transient ischaemic attack between 20 February 1989 and 19 August 1990, inclusive.

MAIN OUTCOME MEASURES

Definite acute "first-ever-in-a-lifetime" (first-ever) and recurrent stroke classified according to standard definitions and criteria.

RESULTS

During the 18-month study period, 536 stroke events occurred among 492 patients, 69% of which were first-ever strokes. The crude annual event rate for all strokes was 258 (95% confidence interval 231-285) per 100,000, and the overall case fatality at 28 days was 24% (95% CI, 20%-28%). The crude annual incidence for first-ever strokes was 178 (95% CI, 156-200) per 100,000; 189 (95% CI, 157-221) per 100,000 in males and 166 (95% CI, 136-196) per 100,000 in females. The corresponding rates, age-adjusted to the "world" population, were 132 (95% CI, 109-155) for males and 77 (95% CI, 60-94) for females.

CONCLUSIONS

In contrast to mortality rates for ischaemic heart disease, the incidence of stroke in Australia appears little different from that for several other Western countries. For both males and females the incidence of stroke rises exponentially with increasing age. Although the sex-dependent difference in the risk of stroke is greatest in middle age, males are at greater risk of stroke even among the most elderly. To determine the incidence of stroke accurately, population-based studies of stroke need exhaustive and overlapping sources of case ascertainment. If only cases admitted to hospital had been used, we would have underestimated the rate of stroke among the most elderly by almost 40%. We estimate that approximately 37,000 people, about 50% of whom are over the age of 75, suffer a stroke each year in Australia.

Marked increase of stroke incidence in men between 1972 and 1990 in Frederiksberg, Denmark

BACKGROUND AND PURPOSE

Stroke incidence declined until the end of the 1970s in the United States, and the decline continued into the 1980s in Japan. The purpose of this study was to determine possible temporal changes of stroke incidence in a European community.

METHODS

A prospective stroke registry was established in the community of Frederiksberg (population, approximately 90,000), Denmark, in the two periods 1972-1974 and 1989-1990. All patients suspected of stroke were clinically evaluated by a neurologist. Only patients with first-ever stroke were included. Complete case ascertainment was ensured by registration of both hospitalized and nonhospitalized patients. Death certificates were also scrutinized.

RESULTS

A total of 927 patients with first-ever stroke was recorded. The annual stroke incidence rate per 1,000 increased by 18% from 2.6 in 1972-1974 to 3.1 in 1989-1990 (p < 0.01). This increase was due solely to a 42% increase in men, in whom stroke incidence rose from 2.1 to 3.0 (p < 0.0005). Incidence was unchanged in women at 3.0 and 3.1, respectively. The incidence rates from 1972-1974 were age and sex adjusted to the 1990 population. After adjustment to the Danish population, stroke incidence in Denmark was 2.0 for all, 2.3 for men, and 1.9 for women. In the second study period computed tomography or necropsy was performed in 85% of cases; 2.4/1,000 had cerebral infarction; 0.20/1,000 had intracerebral hemorrhage; and 0.02/1,000 had subarachnoid hemorrhage.

CONCLUSIONS

In a period when decline in stroke incidence has stopped in the United States and has continued in Japan, a marked increase of stroke incidence in Danish men was observed.

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

BACKGROUND AND PURPOSE

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Primary intracerebral haemorrhage in the Jyväskylä region, central Finland, 1985-89: incidence, case fatality rate, and functional outcome

The age and sex specific incidence rates, the case fatality rates, and the functional outcome of patients with primary intracerebral haemorrhage occurring in a population of 116,000 during a period of four years four months are presented. A total of 158 patients were identified, the diagnosis was confirmed in 78% by CT, and in 22% by necropsy. The crude annual incidence rate was 31/100,000 population, the age specific rates increased from two to 222/100,000 from the age of 30-39 to over 80 years. Men had higher incidence rates between the ages of 40 and 79 years. The short term case fatality rate was high, 27% of patients dying during the first day after onset of symptoms, and 50% were dead at 30 days. After the first month the probability of survival did not differ from an age- and sex-matched average population. Large haematoma volume had an adverse effect on the short term, old age (greater than 70 years) on the long term survival. Ventricular extension, especially when combined with hydrocephalus was a bad omen for short term survival. Infratentorial and large basal ganglionic haematomas, and primary intraventricular haemorrhage carried a worse prognosis than haematomas of other locations. At the end of a median 32 month follow up 55 (35%) of the patients were alive, 51% of these were independent in activities of daily living, 45% were dependent on outside help, and 4% needed constant nursing care. Old age (greater than 70 years), but not the haematoma volume or location, was associated with a poor functional recovery.

Stroke registry in Malmö, Sweden

BACKGROUND AND PURPOSE

A stroke registry covering the city of Malmö, Sweden (population 232,000) was started in January of 1989 to prospectively follow up stroke incidence, recurrence, and fatality rates.

METHODS

Patients with presumed stroke were interviewed within 1 week after admission to the hospital, and their medical records were examined. Continuous validation against hospital diagnosis showed well over 90% of all stroke cases in Malmö to have been included.

RESULTS

Incidence rates per 100,000 residents were 300 for all stroke events and 225 for first-ever stroke, lower than those reported from other studies. The distribution of stroke diagnostic categories was 3% subarachnoid hemorrhage, 10% intracerebral hemorrhage, 50% cerebral infarction, and 38% unspecified stroke. The diagnosis was based on computed tomography in 51% of first-ever stroke cases. Median age was 73.1 years for men and 79.7 years for women. Incidence rates for all stroke diagnostic categories except subarachnoid hemorrhage increased with age. Prior stroke, hypertension, smoking, atrial fibrillation, and diabetes mellitus were major risk factors for all stroke events. The presenting symptoms were hemiparesis in 74%, speech disorder in 49%, and clouded consciousness in 19% of the patients. The overall case-fatality rate at 30 days was 15%; the rate for intracerebral hemorrhage was 37% and that for cerebral infarction was 10%.

CONCLUSIONS

Our findings confirm the value of a stroke registry for stroke epidemiology purposes and as a tool for specific stroke research.