Handicap after stroke: how does it relate to disability, perception of recovery, and stroke subtype?: the north North East Melbourne Stroke Incidence Study (NEMESIS)

BACKGROUND AND PURPOSE

Knowledge of patterns of handicap after stroke and of the relationship among handicap, disability, perception of recovery, and stroke subtype is limited. The aim of this study was to assess handicap 3 and 12 months after first-ever stroke in a community-based study.

METHODS

All strokes occurring in a population of 133 816 people were found and assessed. Patients were classified as having cerebral infarction (CI) or intracerebral hemorrhage (ICH) according to imaging or autopsy findings. Cases of CI were categorized using the Oxfordshire stroke classification. Handicap, disability, and perception of recovery were assessed 3 and 12 months after stroke using the London Handicap Scale, Barthel Index, and the question "Have you made a complete recovery from your stroke?" The association between disability and handicap was examined using Pearson's correlation. Differences in handicap among subtypes of CI were evaluated using one-way ANOVA.

RESULTS

There were 264 cases of CI or ICH. Of surviving patients, 113 (59%) were assessed at 3 months and 107 (64%) at 12 months. The domains of handicap most affected were physical independence and occupation. Only half the variance in handicap was due to disability. Of patients without disability, those who claimed complete recovery were less handicapped than those who claimed incomplete recovery. Patients with total anterior circulation infarction were more handicapped at 3 and 12 months than those with other subtypes of CI.

CONCLUSIONS

Stroke patients were handicapped across many domains. Handicap is only partly explained by disability. Stroke subtype should be considered in the interpretation of outcome data.

Reduced risk of intracerebral hemorrhage with dynamic recreational exercise but not with heavy work activity

BACKGROUND AND PURPOSE

It is unclear whether intracerebral hemorrhage (ICH) is associated with dynamic or static exercise. Our aim was to assess whether such an association exists.

METHODS

A case-control study was undertaken involving 331 consecutive cases of primary ICH and 331 age- and sex-matched community-based neighborhood controls. Cases, verified by CT or autopsy, were identified from 13 major hospitals in Melbourne, Australia. A questionnaire was used to elicit information about lifetime physical activity at leisure and work and other potentially confounding factors.

RESULTS

Individuals undertaking recent regular dynamic exercise exhibited an odds ratio (OR) for ICH of 0.63 (95% CI 0.39 to 1.01) when adjustment was made for all potential confounding factors, except hypertension, cholesterol, and body mass index. Among men and women separately, the ORs were 0.51 (95% CI 0.27 to 0.97) and 1.22 (95% CI 0.52 to 2.87), respectively. When hypertension, cholesterol, and body mass index were also included in the multivariate model, the OR among men was 0.57 (95% CI 0.28 to 1.14). There was no association between physical activity at work and ICH (OR 1.14, 95% CI 0.58 to 2.25).

CONCLUSIONS

These results provide preliminary evidence for a role of exercise in reducing the likelihood of ICH among men. In women, the CI was wide, and the association was not statistically significant. There was further support that factors other than blood pressure status, cholesterol, and body mass index may play a role in the observed inverse association between dynamic exercise and ICH among men.

Cost of stroke in Australia from a societal perspective: results from the North East Melbourne Stroke Incidence Study (NEMESIS)

BACKGROUND AND PURPOSE

Accurate information about resource use and costs of stroke is necessary for informed health service planning. The purpose of this study was to determine the patterns of resource use among stroke patients and to estimate the total costs (direct service use and indirect production losses) of stroke (excluding SAH) in Australia for 1997.

METHODS

An incidence-based cost-of-illness model was developed, incorporating data obtained from the North East Melbourne Stroke Incidence Study (NEMESIS). The costs of stroke during the first year after stroke and the present value of total lifetime costs of stroke were estimated.

RESULTS

The total first-year costs of all first-ever-in-a lifetime strokes (SAH excluded) that occurred in Australia during 1997 were estimated to be A$555 million (US$420 million), and the present value of lifetime costs was estimated to be A$1.3 billion (US$985 million). The average cost per case during the first 12 months and over a lifetime was A$18 956 (US$14 361) and A$44 428 (US$33 658), respectively. The most important categories of cost during the first year were acute hospitalization (A$154 million), inpatient rehabilitation (A$150 million), and nursing home care (A$63 million). The present value of lifetime indirect costs was estimated to be A$34 million.

CONCLUSIONS

Similar to other studies, hospital and nursing home costs contributed most to the total cost of stroke (excluding SAH) in Australia. Inpatient rehabilitation accounts for approximately 27% of total first-year costs. Given the magnitude of these costs, investigation of the cost-effectiveness of rehabilitation services should become a priority in this community.

Incidence of the major stroke subtypes: initial findings from the North East Melbourne stroke incidence study (NEMESIS)

BACKGROUND AND PURPOSE

Population-based stroke incidence studies are the only accurate way to determine the number of strokes that occur in a given society. Because the major stroke subtypes have different patterns of incidence and outcome, information on the natural history of stroke subtypes is essential. The purpose of the present study was to determine the incidence and case-fatality rate of the major stroke subtypes in a geographically defined region of Melbourne, Australia.

METHODS

All suspected strokes that occurred among 133 816 residents of suburbs north and east of Melbourne, Australia, during a 12-month period of 1996 and 1997 were identified and assessed. Multiple overlapping sources were used to ascertain cases, and standard criteria for stroke and case-fatality were used. Stroke subtypes were defined by CT, MRI, and autopsy.

RESULTS

Three hundred eighty-one strokes occurred among 353 persons during the study period, with 276 (72%) being first-ever-in-a-lifetime strokes. Of these, 72.5% (95% CI 67.2% to 77.7%) were cerebral infarction, 14.5% (95% CI 10.3% to 18.6%) were intracerebral hemorrhage, 4.3% (95% CI 1.9% to 6.8%) were subarachnoid hemorrhage, and 8.7% (95% CI 5.4% to 12.0%) were stroke of undetermined type. The 28-day case-fatality rate was 12% (95% CI 7% to 16%) for cerebral infarction, 45% (95% CI 30% to 60%) for intracerebral hemorrhage, 50% (95% CI 22% to 78%) for subarachnoid hemorrhage, and 38% (95% CI 18% to 57%) for stroke of undetermined type.

CONCLUSIONS

The overall distribution of stroke subtypes and 28-day case-fatality rates are not significantly different from those of most European countries or the United States. There may, however, be some differences in the incidence of subtypes within Australia.

Acute Stroke: A population based study of factors influencing delays in hospital arrival. Preliminary results

P155

For acute stroke therapy, most stroke patients are ineligible due to delays in presenting to hospital. Previous studies have largely been hospital based, lacking specific information about the factors influencing non hospitalised patients. To plan for acute stroke care in the new millennium, we need to identify factors that may help increase the proportion eligible for these treatments. Arrival times were assessed for patients accrued in the NorthEast Melbourne Stroke Incidence Study (NEMESIS), a large population based stroke incidence study in Australia. Patients were identified using multiple overlapping sources including 60 hospitals. Stroke onset and hospital arrival times were assessed by review of medical records and interviews with the patient or next of kin. In this preliminary analysis, we assessed 254 stroke events among 244 patients. Two hundred and twenty seven were first-ever-in-a-life time strokes. The mean age was 75 years and 40% were male. In 254 events, 7% never attended hospital and 9% were in-patient strokes. Non attenders were older (mean age 79 years), predominantly female (88%) and 65% resided in nursing homes. Median hospital arrival time for the remaining 84%, was 9.1 hours (range 25 minutes to 1 month). Thirty percent of patients presenting to hospital arrived within 3 hours of the event, and 74% within the first 24 hours. Delays were greater with contact with the General Practitioner, living alone or in patients with a history of dementia. Factors associated with earlier arrival included ambulance transport, dense hemiplegia, impaired consciousness and sub-arachnoid haemorrhage. In this preliminary analysis, we have identified factors that affect hospital arrival times. Many non hospitalised patients may be ineligible for treatment due to pre existing disability or old age, reflected in their need for nursing home accommodation. Of those who attend hospital, potentially a greater proportion of the stroke population could be eligible for acute therapies if delays in arrival could be addressed. Strategies to improve early attendance need to be targeted at both the patient and the General Practitioner.

Stroke incidence on the east coast of Australia: the North East Melbourne Stroke Incidence Study (NEMESIS)

BACKGROUND AND PURPOSE

Community-based stroke incidence studies are the most accurate way of explaining mortality trends and developing public health policy. The purpose of this study was to determine the incidence of stroke in a geographically defined region of Melbourne, Australia.

METHODS

All suspected strokes occurring in a population of 133 816 residents in suburbs north and east of Melbourne, Australia, during a 12-month period of 1996 and 1997 were found and assessed. Multiple overlapping sources were used to ascertain cases, and standard definitions and criteria for stroke and case fatality were used.

RESULTS

A total of 381 strokes occurred among 353 people during the study period, 276 (72%) of which were first-ever-in-a-lifetime strokes. The crude annual incidence rate (first-ever strokes) was 206 (95% CI, 182 to 231) per 100 000 per year overall, 195 (95% CI, 161 to 229) for males, and 217 (95% CI, 182 to 252) for females. The corresponding rates adjusted to the "world" population were 100 (95% CI, 80 to 119) overall, 113 (95% CI, 92 to 134) for males, and 89 (95% CI, 70 to 107) for females. The 28-day case fatality rate for first-ever strokes was 20% (95% CI, 16% to 25%).

CONCLUSIONS

The incidence rate of stroke in our population-based study is similar to that of many European studies but is significantly higher than that observed on the west coast of Australia.

Interrater reliability of the National Institutes of Health Stroke Scale: rating by neurologists and nurses in a community-based stroke incidence study

The reliability of the National Institutes of Health Stroke Scale (NIHSS) for use by trained neurologists in clinical trials of acute stroke has been established in several hospital-based studies. However, it also has the potential for application in community-based settings and to be used by nonneurologists: issues which have not been explored before. Hence, we aimed to determine the reliability of the NIHSS when administered by research nurses within the existing North Eastern Melbourne Stroke Incidence Study. Using the NIHSS, thirty-one consecutively registered stroke patients were assessed by 2 neurologists and 1 of 2 trained research nurses. The interrater reliability of observations was compared using weighted and unweighted kappa statistics and intraclass correlation coefficients (ICC). There was a high level of agreement for total scores between the 2 neurologists (ICC = 0.95) and between each neurologist and research nurse (ICC = 0.92 and 0.96). While there was moderate to excellent agreement among neurologists and research nurse (weighted kappa > 0.4) for the majority of the NIHSS items, there was poor agreement for the component 'limb ataxia'. Overall, agreement between nurse and neurologist for individual items was not significantly different from agreement between neurologists. It appears that in both hospital and community settings, trained research nurses can administer the NIHSS with a reliability similar to stroke-trained neurologists. This ability could be used to advantage in large community-based trials and epidemiological studies.

Heavy drinking, but not moderate or intermediate drinking, increases the risk of intracerebral hemorrhage

An increased risk of intracerebral hemorrhage among heavy consumers of alcohol has been demonstrated in several epidemiologic studies. The effect of moderate or intermediate intakes is, however, unclear. Although several studies provide evidence for a protective effect, this conclusion may be spurious, resulting from the inclusion, within the zero intake (reference) group, of past drinkers who have recently abstained for health reasons. The present study describes the relation between alcohol consumption and intracerebral hemorrhage among 331 case-control pairs recruited in Melbourne, Australia. Heavy drinking was associated with an increased risk of intracerebral hemorrhage (odds ratio (OR) 3.4, 95% confidence interval (CI) = 1.4-8.4). The odds ratio of intracerebral hemorrhage with moderate drinking, when compared with never drinkers, was 0.7, (95% CI = 0.4-1.2) and was 0.6 (95% CI = 0.4-1.0) when compared with nondrinkers (never drinkers plus past drinkers). Wine drinkers were apparently protected from intracerebral hemorrhage (OR 0.5, 95% CI = 0.2-0.9). These results are consistent with the possibility that moderate drinking may confer protection from intracerebral hemorrhage, but this protection may be less than that previously reported.

Ischemic stroke risk and passive exposure to spouses' cigarette smoking. Melbourne Stroke Risk Factor Study (MERFS) Group

OBJECTIVES

This study investigated the association between ischemic stroke risk and passive exposure to cigarette smoking.

METHODS

Risk factors among 452 hospitalized cases of first-episode ischemic stroke were compared with 452 age- and sex-matched "neighbor-hood" controls.

RESULTS

The risk of stroke was twice as high for subjects whose spouses smoked as for those whose spouses did not smoke (95% confidence interval = 1.3, 3.1), after adjustment for the subject's own smoking, heart disease, hypertension, diabetes, and education level. These results were confirmed when analysis was limited to those who never smoked.

CONCLUSIONS

These findings provide evidence that spousal smoking may be a significant risk factor for ischemic stroke.

Risk of primary intracerebral haemorrhage associated with aspirin and non-steroidal anti-inflammatory drugs: case-control study

OBJECTIVE

To examine the association between use of aspirin or other non-steroidal anti-inflammatory drugs and intracerebral haemorrhage.

DESIGN

Case-control study.

SETTING

13 major city hospitals in the Melbourne and metropolitan area.

SUBJECTS

331 consecutive cases of stroke verified by computed tomography or postmortem examination, and 331 age (+/- 5 years) and sex matched controls who were community based neighbours.

INTERVENTIONS

Questionnaire administered to all subjects either directly or by proxy with the next of kin. Drug use was validated by reviewing prescribing records held by the participants' doctors.

MAIN OUTCOME MEASURES

Previous use of aspirin or other non-steroidal anti-inflammatory drugs.

RESULTS

Univariate analysis showed no increased risk of intracerebral haemorrhage with low dose aspirin use in the preceding 2 weeks. Using multiple logistic regression to control for possible confounding factors, the odds ratio associated with the use of aspirin was 1.00 (95% confidence interval 0.60 to 1. 66, P=0.998) and the odds ratio associated with the use of other non-steroidal anti-inflammatory drugs was 0.85 (0.45 to 1.61, P=0. 611) compared with respective non-users in the preceding fortnight. Moderate to high doses of aspirin (>1225 mg/week spread over at least three doses) yielded an odds ratio of 3.05 (1.02 to 9.14, P=0. 047). There was no evidence of an increased risk among subgroups defined by age, sex, blood pressure status, alcohol intake, smoking, and the presence or absence of previous cardiovascular disease.

CONCLUSIONS

No increase in risk of intracerebral haemorrhage was found among aspirin users overall or among those who took low doses of the drug or other non-steroidal anti-inflammatory drugs. These data provide evidence that doses of aspirin usually used for prophylaxis against vascular disease produce no substantial increase in risk of intracerebral haemorrhage.

The risk of intracerebral haemorrhage with smoking. The Melbourne Risk Factor Study Group

To determine whether smoking contributes to the risk of primary intracerebral haemorrhage (ICH) a case-control study was carried out on 331 consecutive cases of first-episode ICH as verified by computed tomography. Patients were age- and sex-matched to 331 community-based controls. Unlike other forms of stroke where smoking is an established risk factor, there was no increase in risk of ICH with smoking in this study (odds ratio, OR, 1.07, 95% confidence interval, CI, 0.631.81). Similar ratios were obtained for past and current smokers. Neither the amount smoked nor the duration of smoking were associated with ICH. Further investigation, however, revealed an interaction between smoking and hypertension on the risk of ICH that was similar regardless of the amount of cigarettes currently smoked and was largely seen to be a phenomenon in men (OR 8.13, 95% CI 2.0432.42). This interaction is a new finding, but the post-hoc nature of this analysis requires that it be further tested, preferably in a large prospective study.

Three important subgroups of hypertensive persons at greater risk of intracerebral hemorrhage. Melbourne Risk Factor Study Group

Hypertension as a risk factor for intracerebral hemorrhage (ICH) is poorly quantified, particularly in the setting of the use of modern antihypertensive agents. To investigate this, we studied 331 consecutive hospital cases of primary ICH verified by computed tomography or autopsy, occurring during the period 1990 through 1992, and 331 age- and sex-matched community-based control subjects in a city-wide study involving 13 hospitals. Hypertension approximately doubled the risk of ICH (adjusted odds ratio [OR], 2.45; 95% confidence interval [CI], 1.61 to 3.73). The OR associated with hypertension was significantly greater among those who had ceased taking medications, supervised and unsupervised (OR, 4.98; 95% CI, 2.25 to 11.02), compared with those who had not (OR, 1.95; 95% CI, 1.20 to 3.16), were under the age of 55 years (OR, 7.68; 95% CI, 2.65 to 22.5), or were current smokers (OR, 6.12; 95% CI, 2.29 to 16.35). The presence of hypertension did not influence size or location of the hemorrhage. However, those dying from ICH displayed a greater risk of ICH due to hypertension than survivors, with the ratio of the two ORs being 5.47 (95% CI, 1.23 to 24.44). These findings provide evidence for a greater increase in risk of ICH due to hypertension among younger persons, current smokers, and those discontinuing antihypertensive therapy. This is the first direct evidence for a link between stopping antihypertensive medication use and stroke risk; targeting these individuals for more intensive monitoring and education on the importance of risk factor modification may help to reduce the impact of this form of stroke.

Risk factors for stroke due to cerebral infarction in young adults

BACKGROUND AND PURPOSE

Stroke in the young is particularly tragic because of the potential for a lifetime of disablement. More than 10% of patients with stroke due to cerebral infarction are aged 55 years or younger. While a number of studies have addressed the issue of stroke mechanism in the young, quantitation of risk factors has rarely been undertaken. Given the importance of risk factor assessment in primary prevention, we aimed to assess this using case-control methodology in a hospital-based series and community-based control subjects.

METHODS

A total of 201 consecutive patients with first-onset stroke due to cerebral infarction aged 15 to 55 years (mean, 45.5 years) were accrued from four teaching hospitals during 1985 to 1992 and compared with their age- and sex-matched neighborhood controls. Information concerning potential risk factor exposure status was collected by structured questionnaire at interview. Stroke risks were estimated by calculating the odds ratios with multivariate logistic regression.

RESULTS

Significantly increased risk of stroke was found among those with diabetes (odds ratio, 11.6 [95% confidence intervals, 1.2 to 115.2]), hypertension (6.8 [3.3 to 13.9]), heart disease (2.7 [1.1 to 6.4]), current cigarette smoking (2.5 [1.3, 5.0]), and long-term heavy alcohol consumption (> or = 60 g/d) (15.3 [1.0 to 232.0]). However, heavy alcohol ingestion (> or = 60 g) within 24 hours preceding stroke onset was not a risk factor (0.9 [0.3 to 3.4]).

CONCLUSIONS

Diabetes, hypertension, heart disease, current smoking, and long-term heavy alcohol consumption are major risk factors for stroke in young adults. Given that the majority of these factors are either correctable or modifiable, prevention strategies may have the potential to reduce the impact of stroke in this age group.

Risk factors for cerebral hemorrhage in the era of well-controlled hypertension. Melbourne Risk Factor Study (MERFS) Group

BACKGROUND AND PURPOSE

Given that hypertension is now relatively well controlled and use of antiplatelet agents has increased, our primary aims were to investigate the risk of intracerebral hemorrhage (ICH) associated with hypertension and use of antiplatelet agents.

METHODS

In this city-wide case-control study, 370 consecutive cases of primary ICH, verified by CT or autopsy, were identified from one of 13 Melbourne hospitals. Ten subjects (or their next of kin) could not be located and 29 refused to participate, resulting in 331 eventual cases. Patients were aged between 18 and 80 years and had no prior stroke. Population-based control subjects were individually age- (+/- 5 years), sex-, and geographically matched to subject cases. A questionnaire administered to participants (or next of kin) elicited information about prior exposure to various potential risk factors.

RESULTS

Hypertension approximately doubled the risk of ICH (odds ratio, 2.55; 95% confidence interval, 1.72 to 3.79). The use of aspirinlike drugs, in doses used for secondary prevention of ischemic stroke or cardiac disease, was not associated with an increased risk of ICH (odds ratio, 0.66; 95% confidence interval, 0.20 to 2.21). Factors associated with a reduced risk of ICH were a history of cardiovascular disease, arthritis, or high cholesterol level; being moderately overweight or using hormone replacement therapy; and drinking coffee.

CONCLUSIONS

Hypertension was the most important risk factor for ICH but not as high as previously reported, nor was it higher than that reported for ischemic stroke. There was no evidence for any association between the use of aspirinlike drugs and ICH.