Current issues of ACP Journal Club are published in Annals of Internal Medicine


Prognosis

After a first-ever stroke mortality was increased, especially in the first 30 days

ACP J Club. 1993 Nov-Dec;119:83. doi:10.7326/ACPJC-1993-119-3-083


Source Citation

Dennis MS, Burn JP, Sandercock PA, et al. Long-term survival after first-ever stroke: The Oxfordshire Community Stroke Project. Stroke. 1993 Jun;24:796-800.


Abstract

Objective

To determine the incidence of death after a first-ever stroke in patients registered with the Oxfordshire Community Stroke Project.

Design

Inception cohort followed for a maximum of 6.5 years.

Setting

Population-based study in the United Kingdom.

Patients

675 patients (mean age 72 y, 53% women) with a first stroke identified in a community-based stroke register. The pathologic type of the first stroke was cerebral infarction in 545 (81%), primary intracerebral hemorrhage in 66 (10%), subarachnoid hemorrhage in 33 (5%), and unknown in 31 (5%).

Assessment of prognostic factors

Age, sex, and pathologic type of the first stroke were noted. Follow-up assessments were done at 1, 6, and 12 months, and annually thereafter. Symptoms of transient ischemic attack, recurrent stroke, and myocardial infarction were documented.

Main outcome measures

Mortality classified as first-stroke deaths, recurrent-stroke deaths, cardiovascular deaths, nonvascular deaths, and unclassified deaths. The cause of death was determined by reviewing all available clinical evidence including hospital, general practitioner, and autopsy records.

Main results

The risks for death during the first 30 days and during the first year were 19% (95% Cl 16% to 22%) and 31% (Cl 27% to 34%), respectively. For those surviving at least 30 days or for at least 1 year, the average annual risks for death up to 5 years were 9.1% (Cl 8.1% to 10.4%) and 6.6% (Cl 4.6% to 8.8%), respectively. In patients who survived for 30 days, the risk for dying during the rest of the first year was 15% higher than in subsequent years. Stratification by age showed that older patients had a worse prognosis during the early period after the stroke and throughout the follow-up period (P < 0.001). The risk for dying in the first year after a first stroke caused by cerebral infarction was 22.1% (Cl 18.9% to 26.9%). The data on the risks for dying in the first year because of intracranial hemorrhage and subarachnoid hemorrhage were unreliable because few patients survived beyond 30 days. For those patients who survived at least 30 days, 36% of deaths were caused by the first or recurrent stroke, and 34% were because of other vascular causes.

Conclusions

In an unselected, community-based population with first stroke, the risk for dying remained elevated for several years but was particularly high in the first 30 days.

Sources of funding: Medical Research Council of Great Britain and the Stroke Association.

For article reprint: Dr. M.S. Dennis, Department of Clinical Neurosciences, Western General Hospital, Edinburgh, Scotland EH4 2XU, UK. FAX 44-31-332-5150.


Commentary

The study by Dennis and colleagues is important because it is community-based. Patients presenting with stroke are very high-risk patients who should be treated aggressively, not only with medical treatment for atherosclerotic risk factors, such as hyperlipidemia (1). They should also be considered for carotid endarterectomy in appropriate circumstances. The North American Symptomatic Carotid Endarterectomy Trial (NASCET) showed a reduction in 2-year risk for stroke and death from 24% in the group randomized to medical therapy (a risk figure remarkably close to that reported in the study by Dennis and colleagues) to 9% in patients randomized to surgery for symptomatic severe ( 70%) carotid stenosis (2). The high risk reported in the study by Dennis and colleagues supports the observation that it is no longer adequate management for patients with stroke or transient ischemic attacks to simply recommend that they take aspirin and cross their fingers. The cause of the stroke must be identified; if they have severe symptomatic carotid stenosis and are medically fit for surgery and an expert surgeon is available, endarterectomy should be offered.

In this study, intracerebral hemorrhage accounted for only 10% of first strokes. Improved detection and treatment of hypertension may have led to a decline in the proportion of strokes caused by intracerebral hemorrhage (3).

J. David Spence, MD
University of Western OntarioLondon, Ontario, Canada


Commentary Update

The study by Dennis and colleagues is important because it is community-based. It confirms that patients with cerebral vascular disease have a very high risk, not only for stroke, but also for cardiac events (4). They should receive aggressive treatment: In addition to smoking cessation, diet, blood pressure control and aspirin, they should be regarded as candidates for lipid lowering therapy (5, 6). Vitamin treatment for hyper-homocyst(e)inemia may also be considered (7). For patients with symptomatic severe carotid stenosis, endarterectomy is warranted (8); in asymptomatic cases and in those with lesser degrees of stenosis, aggressive medical management may be appropriate (9).


References

1. Bots ML, Breslau PJ, Briet E, et al. Cardiovascular determinants of carotid artery disease. The Rotterdam elderly study. Hypertension. 1992;19:717-20.

2. North American Symptomatic CarotidEndarterectomy Trial collaborators. Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade carotid stenosis. N Engl J Med. 1991;325:445-53.

3. Spence JD. Antihypertensive drugs and prevention of atherosclerotic stroke. Stroke. 1986;17:808-10.

4. Chimowitz MJ, Weiss DG, Cohen SL, et al. Cardiac prognosis of patients with carotid stenosis and no history of coronary artery disease. Veteran's Affairs Cooperative Study Group 167. Stroke. 1994;25:759-65.

5. Bots ML, Breslau PJ, Briet E, et al. Cardiovascular determinants of carotid artery disease. The Rotterdam Elderly Study. Hypertension. 1992;19:717-20.

6. Hachinski VC, Graffagnino C, Beaudry M, et al. Lipids and stroke: a paradox resolved. Arch Neurol. 1996;53:303-8.

7. Peterson JC, Spence JD. Vitamins and progression of atherosclerosis in hyper-homocyst(e)inemia. [Letter]. Lancet. 1998;351:263.

8. North American Symptomatic Carotid Endarterectomy Trial Collaborators. Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade carotid stenosis. N Engl J Med. 1991;325:445-53.

9. Perry JR, Szalai JP, Norris JW. Consensus against both endarterectomy and routine screening for asymptomatic carotid artery stenosis. Canadian Stroke Consortium. Arch Neurol. 1997;54:25-8.