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

Abstract

ObjectiveTo determine the incidence and case fatality of seven distinct subtypes of stroke in Perth, Western Australia. Design and settingA population‐based descriptive epidemiological study. SubjectsAll 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 measuresThe 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. ResultsOver the 18‐month study period 538 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. ConclusionsIn 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.

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

“…Incidences were reported separately for women and men by age category in 16 studies 5 6 9 10 16 18–20 22 27 45 49 50 52 54 57. In this subset of studies, the women–men ratio ranged from 0.65 (95% CI 0.51 to 0.82) to 1.50 (95% CI 1.07 to 2.10).…”

“…Twenty studies, including the nine studies with only age specified subsets of the population, reported separately on incidences per age group 5 6 8–10 16 18–20 22 27 36 45 49 50 52 54 57 60 64. The overall incidence of these 20 studies was 13.9 (95% CI 13.3 to 14.5) per 100 000 person-years.…”

“…Eighteen studies reported incidences for men and women separately 5 9 10 17 18 20 22 27 29 35 44 45 47 49 50 52 54 57. The overall incidence in this subset of studies was 10.5 (95% CI 9.9 to 11.2) per 100 000 person-years; the incidence for men was 9.2 (95% CI 8.4 to 10.2) and for women 11.5 (95% CI 10.6 to 12.6).…”

The Impact of Neuropsychological Deficits on Functional Stroke Outcomes

“…As noted previously, stroke is a heterogeneous disorder that consists of major pathological types, each of which has differing aetiologies (Donnan, McNeil, Adena, Doyle, O'Malley, et al, 1989;Thrift, McNeil, Forbes, & Donnan, 1996, incidence rates (Sudlow & Warlow, 1997;Petty, Brown, Whisnant, Sicks, O'Fallon, et al, 2000), management (Schievink, 1997; National Institute of Neurological Disorders and Stroke rt-PA Stroke Study Group, 1995), and short to medium-or long-term outcomes (Anderson, et al, 1993;Bamford et al, 1991;Brown, Whisnant, Sicks, O'Fallon, & Wiebers, 1996;Longstreth, Nelson, Koepsell, & van Belle, 1993;Thrift, Dewey, Macdonell, McNeil, & Donnan, 2000). If specific stroke subtypes are shown to have differing neuropsychological outcomes, then the need for community and rehabilitation services, educational and interventional programs in stroke patients and their families could also be different (Sturm et al, 2002).…”

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

“…Because of the poor outcome in patients developing intracerebral haemorrhage,13 – 15 there has been concern that intracerebral haemorrhage might offset the benefits of aspirin treatment, particularly when used in low risk settings such as for the primary prevention of coronary heart disease. 2 16…”