Explaining stroke mortality trends

Analysis of the effect of patients' health status on efficiency: Application of data envelopment analysis in healthcare

The effective and efficient operation of public healthcare systems is more and more important as a consequence of the increasing amount of money spent on their operation. For this reason, accurate and science-based efficiency information is needed for managers and healthcare policy makers. The evaluation of the efficiency in this sector is particularly difficult because several measures and indicators are used. Data envelopment analysis (DEA) can provide aggregate and overall measures of efficiency. The purpose of this paper is the examination of the efficiency of in-patient rehabilitation units curing musculoskeletal disorders in Hungary. The research presented focuses on rehabilitation units which attend to patients recovering from stroke or other acquired brain injuries. Output-oriented, slack-based DEA models are applied for the evaluation of in-patient rehabilitation units using data of a national survey. The novelty of the method presented is the consideration of the change in patients' functional status when efficiency is evaluated using DEA.

Diagnostic accuracy of panoramic radiography in the detection of calcified carotid artery atheroma: a meta-analysis

OBJECTIVE

To determine the diagnostic accuracy of panoramic radiography (PR) in detecting calcified carotid artery atheroma (CCAA) compared with Doppler ultrasonography or angiography (the reference standard).

SOURCES

Cochrane, LILACS, PubMed, Scopus, Web of Science, Google Scholar, Open Grey, and ProQuest were searched. The reference lists of the included studies were also screened.

DATA

Observational studies.

METHODS

Only studies comparing the diagnostic accuracy of PR in detecting CCAA to Doppler ultrasonography or angiography (the reference standard) were included. The primary outcome measures were sensitivity and specificity. The secondary outcomes were negative predictive values, positive predictive values, diagnostic odds ratios, likelihood ratios (positive and negative), receiver operating characteristic curves, accuracy, and Youden's index. Two reviewers independently participated in the study selection, data extraction, and risk of bias assessment without language restriction. Risk of bias was assessed thought QUADAS-2, and the level of evidence was assessed through GRADE.

RESULTS

A total of 773 citations were identified after duplicates were removed, and 12 studies including 1002 patients were included in the final study. The sensitivity and specificity of the different selected studies varied substantially, with sensitivity ranging from 0.31 to 0.95 and specificity from 0.19 to 0.99.

CONCLUSIONS

Most studies reported excellent sensitivity and good specificity. The diagnostic accuracy of PR was good or excellent in 50% of the studies.

CLINICAL SIGNIFICANCE

The identification of CCAA by PR can be a risk predictor for stroke when used as a secondary screening tool.

External Validation of Pooled Cohort Risk Equations to Predict 1-Year Clinical Outcome in Ischemic Stroke Patients

Background

The present study aimed to validate the pooled cohort risk (PCR) equations in a Chinese ischemic stroke population and to explore its prognostic value in predicting stroke recurrence, coronary heart disease, and vascular death.

Material/Method

Patients were selected from the China National Stroke Registry. The C statistic was used to examine the clinical prediction of the scores. To analyze the relevant risk factors, univariate and multivariate logistic regressions were performed.

Results

Out of a total of 22 216 patients, 8287 patients (including 7652 acute ischemic stroke [AIS] and 635 transient ischemic attack [TIA] patients) were selected and enrolled in the study. At 1-year follow-up, for stroke recurrence rate, the C statistic value was 0.584 in AIS patients and 0.573 in all patients. For non-fatal myocardial infarction, the C statistic value was 0.533 in AIS patients and 0.493 in all patients. For vascular death, the C statistic value was 0.592 in AIS patients and 0.592 in all patients. For all events, the C statistic value was 0.582 in AIS patients and 0.575 in all patients. For AIS patients, the 12-month cumulative rates for recurrent stroke, vascular death, and combined vascular events were higher in the high-PCR group (PCR ≥20%).

Conclusions

Pooled cohort risk equations may serve as potential tools to predict and stratify the 1-year risk of recurrent stroke and combined vascular events in AIS/TIA patients in China.

Salbutamol inhibits lipopolysaccharide-induced inflammatory responses in rat peritoneal macrophages

Acute and chronic inflammatory diseases are associated with the induction of inducible nitric oxide synthase (iNOS) and inducible heme oxygenase (HO-1). These inducible enzymes are up-regulated in macrophages subjected to inflammatory stimuli and oxidative stress. beta(2)-Adrenoceptor (AR) agonists, which function as bronchial dilators, are widely used for the treatment of asthma and chronic obstructive pulmonary disease (COPD). We examined whether salbutamol, a classical beta(2)-AR agonist, inhibits the induction of proinflammatory cytokines and stress inducible proteins. Rat macrophages obtained from the abdominal cavity were incubated with lipopolysaccharide (LPS) with or without salbutamol. Induction by LPS of tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 was significantly inhibited (P < 0.05) by salbutamol treatment. Induction by LPS of iNOS mRNA and protein was also significantly inhibited (P < 0.05) by salbutamol. LPS-mediated increases in HO-1 mRNA and protein were not appreciably affected by salbutamol. One of the anti-inflammatory mechanisms of salbutamol was thus found to be inhibition of induction by LPS of extracellular stimulus-responsive kinase (ERK) 1/2 in macrophages. These findings suggest that salbutamol has the potential for use as an anti-inflammatory agent due to its suppression of LPS-induced TNF-alpha, and IL-6 and iNOS via ERK pathway without affecting HO-1 expression.

Cardiac troponins in the intensive care unit: common causes of increased levels and interpretation

BACKGROUND AND OBJECTIVES

Clinical chemistry is an important component of the diagnosis of many conditions, and advances in laboratory science have brought many new diagnostic tools to the intensive care unit clinician, including new biomarkers of cardiac injury like troponin T and I. Interpretation of these clinical laboratory results requires knowledge of the performance of these tests.

SETTING AND PATIENTS

This article reviews the interpretation and performance of diagnostic markers of myocardial injury in patients with diverse clinical conditions of interest to critical care practitioners.

CONCLUSIONS

Cardiac troponin I and T, regulatory components of the contractile apparatus, are sensitive indicators of myocardial injury and have become central to the diagnosis of myocardial infarction. The troponins are also released in a number of clinical situations in which thrombotic complications of coronary artery disease and resultant acute myocardial infarction have not occurred. These situations include conditions like pulmonary embolism, sepsis, myocarditis, and acute stroke. Elevated troponins in these conditions are thought to emanate from injured myocardial cells and, in most circumstances, have been associated with adverse outcomes. Practitioners should be mindful of the wide spectrum of diseases that may result in elevated troponin when interpreting these measurements.

An inhaled inducible nitric oxide synthase inhibitor reduces damage of Candida-induced acute lung injury

Excessive nitric oxide (NO) generated by inducible nitric oxide synthase (iNOS) aggravates acute lung injury (ALI) by producing peroxynitrite. We previously showed by immunostaining that the expression of iNOS was suppressed by inhalation of N(G)-nitro-L-arginine methyl ester in mice with Candida-induced ALI. This study tested the hypothesis that a novel iNOS inhibitor suppresses not only iNOS expression, but also iNOS messenger RNA (mRNA) production by interrupting a positive feedback loop at the time of NO production in Candida-induced ALI. Mice were pretreated by inhalation of saline or ONO-1714, a selective iNOS inhibitor, and were given an intravenous injection of Candida albicans to induce ALI. After inhalation of 1 mM aerosolized ONO-1714, the nitrite-nitrate concentration in bronchoalveolar lavage fluid (BALF) at 24 h was significantly lower than that after inhalation of saline. Tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) levels and neutrophils in BALF were decreased by inhalation of ONO-1714. Inhalation of ONO-1714 markedly suppressed nitrotyrosine production and inhibited the expression of iNOS mRNA as well as proteins in the lung. Survival was prolonged by inhalation of ONO-1714. We conclude that pretreatment with inhaled ONO-1714 suppresses the production of peroxinitrite and decreases oxidative stress associated with peroxinitrite in Candida-induced ALI.

Population-based study of event-rate, incidence, case fatality, and mortality for all acute vascular events in all arterial territories (Oxford Vascular Study)

BACKGROUND

Acute coronary, cerebrovascular, and peripheral vascular events have common underlying arterial pathology, risk factors, and preventive treatments, but they are rarely studied concurrently. In the Oxford Vascular Study, we determined the comparative epidemiology of different acute vascular syndromes, their current burdens, and the potential effect of the ageing population on future rates.

METHODS

We prospectively assessed all individuals presenting with an acute vascular event of any type in any arterial territory irrespective of age in a population of 91 106 in Oxfordshire, UK, in 2002-05.

FINDINGS

2024 acute vascular events occurred in 1657 individuals: 918 (45%) cerebrovascular (618 stroke, 300 transient ischaemic attacks [TIA]); 856 (42%) coronary vascular (159 ST-elevation myocardial infarction, 316 non-ST-elevation myocardial infarction, 218 unstable angina, 163 sudden cardiac death); 188 (9%) peripheral vascular (43 aortic, 53 embolic visceral or limb ischaemia, 92 critical limb ischaemia); and 62 unclassifiable deaths. Relative incidence of cerebrovascular events compared with coronary events was 1.19 (95% CI 1.06-1.33) overall; 1.40 (1.23-1.59) for non-fatal events; and 1.21 (1.04-1.41) if TIA and unstable angina were further excluded. Event and incidence rates rose steeply with age in all arterial territories, with 735 (80%) cerebrovascular, 623 (73%) coronary, and 147 (78%) peripheral vascular events in 12 886 (14%) individuals aged 65 years or older; and 503 (54%), 402 (47%), and 105 (56%), respectively, in the 5919 (6%) aged 75 years or older. Although case-fatality rates increased with age, 736 (47%) of 1561 non-fatal events occurred at age 75 years or older.

INTERPRETATION

The high rates of acute vascular events outside the coronary arterial territory and the steep rise in event rates with age in all territories have implications for prevention strategies, clinical trial design, and the targeting of funds for service provision and research.

Exhaled nitric oxide and hydrogen peroxide concentrations in asthmatic smokers

BACKGROUND

Cigarette smoking is associated with decreased nitric oxide (NO) production and increased oxidative stress in the airways. Exhaled NO levels are not higher in asthmatic smokers than in healthy non-smokers, and the value of exhaled NO for diagnosing asthma in smokers has been questioned.

OBJECTIVES

To compare exhaled NO concentrations between healthy and steroid-naive and steroid-treated asthmatic smokers and non-smokers. To also assess the acute effect of cigarette smoking on exhaled NO and hydrogen peroxide (H(2)O(2)) levels in asthmatic smokers.

METHODS

Exhaled NO was measured by chemiluminescence and exhaled H(2)O(2) spectrophotometrically. In 7 steroid-naive asthmatic smokers exhaled NO and H(2)O(2) was measured both before and 15 min after smoking one cigarette. Data are given as median (range).

RESULTS

Exhaled NO level was significantly higher in steroid-naive asthmatic smokers than in healthy smokers [7.7 (3.4-32.5) ppb vs. 3.2 (2.0-7.2) ppb, p < 0.001]. Exhaled NO values were lower in smokers than in non-smokers both in healthy subjects and in steroid-naive asthmatic patients. Steroid-treated asthmatic smokers had a tendency for lower exhaled NO values [5.4 (1.7-12.0) ppb] compared to steroid-naive asthmatic smokers. Cigarette smoking caused an acute increase in exhaled H(2)O(2) concentrations together with a decrease in exhaled NO concentration.

CONCLUSIONS

Our data suggest that an elevation in exhaled NO concentration is associated with asthma in smokers. This difference may be useful for diagnosing the disease in smokers, but its clinical value needs further evaluation. Acute increase in exhaled H(2)O(2) concentrations suggests that smoking increases the oxidative stress in the asthmatic airways.

Regional Differences in Incidence Rates, Outcome Predictors and Survival of Stroke

The aim of our study was to compare subtype-specific incidence rates, case-fatality rates and outcome predictors in different geographical areas, and decide what drives the variations. Analyzing standardized, prospective stroke registers in the Akita Prefecture, Japan, and in Hungary with catchment areas of more than 1.2 and 1.5 million during the same 18 months, we assumed population and ethnic variations in subtype-specific incidence rates, indicating higher risk of ischemic stroke in Hungary and higher risk of hemorrhagic stroke in Japan. The determinants of 28-day case-fatality rates, at least in part, also varied in different populations. However, survival from stroke was mainly influenced by stroke management.

Relation between troponin T concentration and mortality in patients presenting with an acute stroke: observational study

OBJECTIVE

To assess whether a raised serum troponin T concentration would be an independent predictor of death in patients with an acute ischaemic stroke.

DESIGN

Observational study.

SETTING

Auckland Hospital, Auckland, New Zealand.

SUBJECTS

All 181 patients with an acute ischaemic stroke admitted over nine months in 1997-8, from a total of 8057 patients admitted to the acute medical service.

MAIN OUTCOME MEASURES

Blood samples for measuring troponin T concentration were collected 12-72 hours after admission; other variables previously associated with severity of stroke were also recorded and assessed as independent predictors of inpatient mortality.

RESULTS

Troponin T concentration was raised (>0.1 microgram/l) in 17% (30) of patients admitted with an acute ischaemic stroke. Thirty one patients died in hospital (12/30 (40%) patients with a raised troponin T concentration v 19/151 (13%) patients with a normal concentration (relative risk 3.2 (95% confidence 1.7 to 5. 8; P=0.0025)). Of 17 possible predictors of death, assessed in a multivariate stepwise model, only a raised troponin T concentration (P=0.0002), age (P=0.0008), and an altered level of consciousness at presentation (P=0.0074) independently predicted an adverse outcome.

CONCLUSIONS

Serum troponin T concentration at hospital admission is a powerful predictor of mortality in patients admitted with an acute ischaemic stroke.

Ischemic stroke subtypes : a population-based study of functional outcome, survival, and recurrence

BACKGROUND AND PURPOSE

There is scant population-based information on functional outcome, survival, and recurrence for ischemic stroke subtypes.

METHODS

We identified all residents of Rochester, Minnesota, with a first ischemic stroke from 1985 through 1989 using the resources of the Rochester Epidemiology Project medical records linkage system. After reviewing medical records and imaging studies, we assigned patients to 4 major ischemic stroke categories based on National Institute of Neurological Diseases and Stroke Data Bank criteria: large-vessel cervical or intracranial atherosclerosis with stenosis (ATH, n=74), cardioembolic (CE, n=132), lacunar (LAC, n=72), and infarct of uncertain cause (IUC, n=164). We used the Rankin disability score to assess functional outcome and the Kaplan-Meier product-limit method and Cox proportional hazards regression analysis with bootstrap validation to estimate rates and identify predictors of survival and recurrent stroke among these patients.

RESULTS

Rankin disabilities were different across stroke subtypes at the time of stroke and 3 months and 1 year later (P=0.001). LAC was associated with milder deficits compared with other subtypes. Mean follow-up among the 442 patients in the cohort was 3.2 years. Estimated rates of recurrent stroke at 30 days were significantly different (P<0.001): ATH, 18.5% (95% CI 9.4% to 27.5%); CE, 5.3% (95% CI 1.2% to 9.6%); LAC, 1.4% (95% CI 0.0% to 4.1%); and IUC, 3. 3% (95% CI 0.4% to 6.2%). After adjusting for age, sex, and stroke severity, infarct subtype was an independent determinant of recurrent stroke within 30 days (P=0.0006; eg, risk ratio for ATH compared with CE=3.3, 95% CI 1.2 to 9.3) but not long term (P=0.07). Four of 25 recurrent strokes within 30 days were procedure-related, each in patients with ATH. Five-year death rates were significantly different (P<0.001): ATH, 32.2% (95% CI 21.1% to 43.2%); CE, 80.4% (95% CI 73.1% to 87.6%); LAC, 35.1% (95% CI 23.6% to 46.0%); and IUC, 48.6% (95% CI 40.5% to 56.7%). With adjustment for age, sex, cardiac comorbidity, and stroke severity, the subtype of ischemic stroke was an independent determinant of long-term (P=0.018; eg, risk ratio for ATH compared with cardioembolic=0.47, 95% CI 0.29 to 0.77) but not 30-day survival (P=0.2).

CONCLUSIONS

Early recurrence rates for ischemic stroke caused by ATH are higher than those for other subtypes and higher than previous non-population-based studies have reported. Some of the increased risk of early recurrence among patients with ATH may be iatrogenic. Patients with LAC have better poststroke functional status than those with other subtypes. Survival is poorest among those with ischemic stroke with a cardiac source of embolism.

Vascular risks and incident dementia: results from a cohort study of the very old

The contribution of vascular pathology to the manifestation of dementia and the importance of vascular risk to measures of cognitive function is being increasingly recognized. In particular, confirmation of this risk points towards approaches for prevention in large sections of the population. Information on determinants of incident dementia is increasing, but still relatively few studies of risk have been based on incident cases of dementia in very elderly populations. In this study based on incident cases of dementia in a population aged 75 and over, vascular risks were obtained from informants of the respondents with incident dementia. When compared with controls the factors associated with incident dementia were history of heart attack (odds ratio 2.9), transient ischaemic attacks (4.8), cerebrovascular accidents (3.4), family history of first-degree relatives with dementia (4.0), and occupational exposure to vibrating instruments (1.4). If only Alzheimer's disease, clinically diagnosed, was included, diabetes (1.4) and a history of dementia in first-degree relatives (6.6) emerged. Thus, vascular risk continues to be of importance in the oldest age groups.

Exogenous nitric oxide regulates the degranulation of human basophils and rat peritoneal mast cells

This study was designed to investigate whether anti-IgE-induced or ionophore A23187-induced histamine release from human basophils is regulated by exogenous nitric oxide (NO), and to assess some similarities between the effect of NO on basophils and that on rat peritoneal mast cells (RPMC). The NO donor, sodium nitroprusside (SNP), inhibited A23187-induced histamine release from crude human basophils and crude RPMC in a dose-dependent fashion. This downregulation was still observed when SNP was washed out just before the cell stimulation, indicating that the effect of SNP was irreversible. The downregulation disappeared in both purified cell populations after the removal of contaminating cells. However, when purified cells were preincubated with SNP in the presence of 5 mM N-acetylcysteine (NAC), increasing the bioavailability of NO, the downregulation was recovered. The presence of NAC significantly augmented the downregulation of SNP on A23187-induced histamine release from both crude cell populations. In contrast, SNP had no effect on anti-IgE-induced histamine release from either crude or purified basophil preparation in the absence of NAC, and SNP plus NAC inhibited anti-IgE-induced histamine release from both cell preparations. The same results were obtained with crude and purified RPMC preparations under the same conditions. These results show that SNP similarly downregulated exocytosis of basophils and RPMC, and acquired the potent effect in the presence of NAC, indicating that exogenous NO plays a part in the regulation of basophil and mast cell activation.

Trends in stroke mortality in Greater London and south east England--evidence for a cohort effect?

OBJECTIVE AND SETTING

To examine time trends in stroke mortality in Greater London compared with the surrounding South East Region of England.

DESIGN

Age-cohort analysis based on routine mortality data.

SUBJECTS

Resident population aged 45 years or more.

MAIN OUTCOME MEASURE

Age specific stroke mortality rates, 1951-92.

MAIN RESULTS

In 1951, stroke mortality was lower in Greater London than the surrounding South East Region in all age bands over 45. It has been declining in both areas but the rate of decline has been significantly slower in Greater London (p < 0.0001). The differences in rates of decline were such that stroke mortality is now higher in Greater London for people under 75. The crossover of age specific stroke mortality rates occurred at different periods in different age bands and is consistent with a cohort effect, with similar rates in Greater London and the surrounding south east for men and women born around 1916-21. This cohort effect does not appear to be consistent with past maternal and neonatal mortality rates in these areas, nor, within the limitations of the data, with the ethnic composition of cohorts.

CONCLUSIONS

There seems to be a cohort effect on stroke mortality which is not explained by past maternal and neonatal mortality. If the decline in stroke mortality continues at its current rate, the Health of the Nation stroke target is unlikely to be achieved in Greater London.

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.

Epidemiology of stroke

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Changes in the sex ratio of stroke mortality in the period of 1955 through 1990

BACKGROUND AND PURPOSE

Stroke mortality worldwide has decreased in men and women in most industrialized countries, except in eastern European countries. The purpose of this study was to compare the sex ratio of stroke mortality between populations and over time. This approach may help to determine the factors influencing this ratio.

METHODS

The sex ratios (men to women) of stroke mortality between ages 55 to 64, 65 to 74, and 75 to 84 years from 27 populations between 1955 and the latest available year were analyzed using World Health Organization data. The relationship between log stroke mortality and age and the relationships between alcohol, animal fat, cigarette consumption, and urinary cation excretion and the sex ratio of stroke mortality were also analyzed.

RESULTS

The mean sex ratio of stroke mortality increased 50%, 34%, and 15% in the three age classes, respectively, over 35 years. Highly significant relationships of log stroke mortality with age exist, which vary between men and women and among countries. In general, stroke mortality changed in the same direction in both sexes but decreased earlier and more rapidly in women than in men. Alcohol consumption and urinary sodium excretion correlated positively and significantly with the sex ratio. The time trends of the sex ratio also correlated positively and significantly with the time trends of cigarette consumption. No relationship with animal fat consumption was found.

CONCLUSIONS

The sex ratio of stroke mortality is increasing with time and decreasing with age. Differences in lifestyle among countries and over the last three decades may contribute partially to these differences in sex ratio.

Identification of stroke-prone patients by panoramic and cervical spine radiography

OBJECTIVE

To determine if calcified atherosclerotic lesions in the region of the bifurcation of the common carotid artery (a major cause of stroke) can be identified by conventional panoramic dental radiography.

METHODS

All those aged 65 years or older, of 500 consecutive out-patients enrolled in the dental clinic for comprehensive treatment and for whom it was possible to obtain a technically satisfactory panoramic radiograph, were included. The radiographs were evaluated for the presence of radiopacities within the soft tissues of the neck at the level of the lower margin of the third cervical vertebra. An antero-posterior cervical spine radiograph was obtained of those individuals with any such calcifications. Medical histories were obtained from patients with suspected lesions in order to determine the presence of risk factors known to be associated with stroke.

RESULTS

Six individuals (4.5% of the final study population) had radiopacities which were confirmed by radiographs of the cervical spine to be calcified atheromas. The medical histories revealed risk factors associated with stroke.

CONCLUSION

Panoramic radiographs obtained during the course of routine dental treatment may demonstrate calcified carotid atheromas in patients at risk of stroke.

Vitamin C and risk of death from stroke and coronary heart disease in cohort of elderly people

OBJECTIVES

To determine whether vitamin C status, as measured by dietary intake and plasma ascorbic acid concentration, is related to mortality from stroke and coronary heart disease in people aged 65 and over.

DESIGN

A 20 year follow up study of a cohort of randomly selected elderly people living in the community who had taken part in the 1973-4 Department of Health and Social Security nutritional survey and for whom dietary and other data had been recorded.

SETTING

Eight areas in Britain (five in England, two in Scotland, and one in Wales).

SUBJECTS

730 men and women who had completed a seven day dietary record and who had no history or symptoms of stroke, cerebral arteriosclerosis, or coronary heart disease when examined by a geriatrician in 1973-4.

RESULTS

Mortality from stroke was highest in those with the lowest vitamin C status. Those in the highest third of the distribution of vitamin C intake had a relative risk of 0.5 (95% confidence interval 0.3 to 0.8) compared with those in the lowest third, after adjustment for age, sex, and established cardiovascular risk factors. The relation between vitamin C intake and stroke was independent of social class and other dietary variables. A similar gradient in risk was present for plasma ascorbic acid concentrations. No association was found between vitamin C status and risk of death from coronary heart disease.

CONCLUSION

In elderly people vitamin C concentration, whether measured by dietary intake or plasma concentration of ascorbic acid, is strongly related to subsequent risk of death from stroke but not from coronary heart disease.

Community-based stroke incidence trends from the 1970s through the 1980s in East Germany

BACKGROUND AND PURPOSE

Stroke mortality has declined in most industrialized countries, but incidence rates have increased in some populations while they remained stable or even decreased in others. This study reports stroke incidence trends in East Germany over the past decades.

METHODS

Prospective community-based stroke registers were run in East Germany over two different time periods: 1972 through 1973 in the Berlin-Lichtenberg district and 1985 through 1988 in 14 districts in the central and southern part of the country. Stroke cases were collected and validated in a uniform way using both the World Health Organization (WHO) recommendations for community stroke registers and the guidelines of the WHO MONICA protocol.

RESULTS

Annual age-adjusted incidence rates of first-ever strokes rose among men aged 25 to 64 years from 48.4 per 100,000 in 1972 through 1973 to 88.0 per 100,000 in 1985 through 1988 (P < .05); incidence rates remained unchanged among women in this age range (52.6 and 52.5 per 100,000, respectively). Age-specific incidence rates increased among men in all age groups up to 74 years. Rising stroke rates were also observed in women under 55 years and between the ages of 65 and 74 years, whereas in women aged 55 to 65 years incidence rates declined by more than a third (P < .05). During the period from 1985 through 1988, stroke rates did not change.

CONCLUSIONS

An increase in stroke incidence was detected that can be associated with a deteriorating risk factor profile in the East German population and, in particular, with hypertension in men.

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.