A prospective reevaluation of transient ischemic attacks as a risk factor for death and fatal or nonfatal cardiovascular events

[Changes in cerebral perfusion in patients undergoing revascularization of carotid artery stenosis]

Ischemic stroke is caused by atherosclerotic lesions in extra- and intracranial arteries in about 25% of cases. Revascularization surgery has been long and widely used for secondary prevention of ischemic stroke in patients with atherosclerotic lesions of the carotid arteries. However, currently the changes in cerebral perfusion in patients with atherosclerotic lesions of brachiocephalic arteries, who underwent surgical revascularization, are still not fully understood. This article highlights the issues of changes of cerebral hemodynamics in patients undergoing surgery on the carotid arteries.

Low risk of vascular events following urgent treatment of transient ischaemic attack: the Aarhus TIA study

BACKGROUND AND PURPOSE

Patients with TIA have a high short-time risk of stroke and an increased long-term risk of ischaemic vascular events compared with the general population. Urgent intervention may reduce short-time stroke risk, but little is known about the effect beyond 3 months. We examined 1-year outcome and risk factor management in patients with TIA after urgent intervention.

METHODS

All patients with TIA referred to Aarhus University Hospital 1 March 2007-28 February 2008 were seen by an acute TIA team (ATT), integrating outpatient care and stroke unit facilities. Preventive treatment was initiated immediately, including fast-track surgery for carotid stenosis. Follow-up including nurse-conducted health counseling was carried out after 7, 90, and 365 days.

RESULTS

A total of 306 patients were included. Stroke, myocardial infarction, or vascular death occurred in 5.2% during 1 year of follow-up. The cumulated stroke rate was 1.6%, 2.0%, and 4.4% after 7, 90, and 365 days, respectively, compared to expected 4.5% [relative risk (RR) 0.36, 95% CI 0.13-0.98] and 7.5% (RR 0.26, 95% CI 0.11-0.63) after 7 and 90 days using ABCD(2) criteria. Recurrent TIA occurred in 10.2% (n = 32). Secondary prevention targets were attained in 47.6% after 1 year. Carotid surgery was performed in 8.1%; median time to operation was 11 days after contact with the ATT.

CONCLUSION

Urgent intervention after TIA by an ATT covering outpatient and stroke unit facilities combined with nurse-conducted health counseling is associated with a low 1-year risk of new vascular events and may improve risk factor control.

Young strokes in Sri Lanka: an unsolved problem

Stroke in young adults is more common in India and Sri Lanka and the reasons for this are not well understood. The current study was conducted to elucidate the risk factors and radiologic features in young people (age < 45 years) with ischemic stroke. Sociodemographic data, stroke risk factor information, and laboratory investigations were recorded in 41 cases with first-ever ischemic stroke. Most common risk factors for stroke in the 15- to 45-year-old age group were: hypertension, 8 (21%); family history of stroke, 7 (18%); transient ischemic attack, 6 (16%); hyperlipidemia, 3 (8.0%); and diabetes, two (5%). Age group younger than 15 years included 3 girls and one had a mass attached to the posterior mitral valve leaflet. Our observations underscore the importance of the presence of hypertension, family history of stroke, and transient ischemic attack in young adults and thus to adopt preventative strategies.

Hyperglycaemia in acute ischaemic stroke is associated with an increased 5-year mortality

BACKGROUND

admission hyperglycaemia (HG) is associated with worse prognosis and higher mortality within 3 months after stroke. Reports on long-term mortality are inconsistent.

OBJECTIVE

to evaluate the influence of admission HG [blood glucose (BG) levels >8 mmol/L] on long-term mortality after ischaemic stroke (IS) and transient ischaemic attack (TIA).

METHODS

consecutive patients with IS or TIA, admitted from January 1997 until December 2002, were retrospectively screened. BG was measured within 3 days from onset of symptoms. Information on the date of death was obtained within 10 years after onset.

RESULTS

a total of 509 patients (78% IS; 22% TIA) were included. Admission HG was present in 28% and 18% of the IS and TIA patients, respectively (P = 0.05). Mean admission BG was 7.6 +/- 3.2 mmol/L in the IS and 6.7 +/- 2.3 mmol/L in TIA (P = 0.002). During a mean observation of 66 +/- 35 months, the overall 1- and 10-year mortality rate was 12% and 51% in IS compared to 4% and 38% in TIA patients (P = 0.004). Normoglycaemic IS patients had a longer median survival than those with HG (113 vs 84 months, P = 0.04). Admission HG did not affect the mortality rates in TIA patients.

CONCLUSION

admission HG is associated with greater mortality rates up to 5 years after stroke but does not influence the survival of TIA patients.

Elderly women have lower rates of stroke, cardiovascular events, and mortality after hospitalization for transient ischemic attack

BACKGROUND AND PURPOSE

Patients with transient ischemic attack (TIA) are at increased risk for stroke, cardiovascular events, and death, yet little is known about whether these risks differ for men and women. We determined whether there are sex-based differences in these outcomes 30 days and 1 year after TIA using a national sample of elderly patients.

METHODS

Rates of 30-day and 1-year hospitalization for TIA (International Classification of Diseases, 9th Revision Code 435), stroke (International Classification of Diseases, 9th Revision Codes 433, 434, and 436), coronary artery disease (International Classification of Diseases, 9th Revision Codes 410 to 414), all-cause readmission, and mortality were determined for fee-for-service Medicare patients >or=65 years of age discharged with a TIA in 2002. Cox proportional hazards models and random-effects logistic models compared outcomes with risk adjustment for demographics, medical history, comorbidities, and prior hospitalizations.

RESULTS

The study included 122063 TIA hospitalizations (mean age, 79.0+/-7.6 years; 62% women; 86% white). Men were younger but had higher rates of cardiac comorbidities than women. Women had lower unadjusted rates of stroke, coronary artery disease, and mortality at 30 days and 1 year after TIA admission. These relationships persisted in risk-adjusted analyses at 30 days for stroke (hazard ratio, 0.70; 95% CI, 0.64 to 0.77), coronary artery disease (hazard ratio, 0.86; 0.74 to 1.00), and mortality (odds ratio, 0.74; 0.68 to 0.82) as well as at 1 year for stroke (hazard ratio, 0.85; 0.81 to 0.89), coronary artery disease (hazard ratio, 0.81; 0.77 to 0.86), and mortality (odds ratio, 0.78; 0.75 to 0.81).

CONCLUSIONS

These data suggest that women have a better prognosis than men within the first year after hospital discharge for a TIA. Additional research is needed to identify factors that may explain these sex-related differences in outcomes.

The relation between questions indicating transient ischaemic attack and stroke in 20 years of follow up in men and women in the Renfrew/Paisley Study

STUDY OBJECTIVE

Transient ischaemic attack (TIA) is often a precursor to stroke, so identification of people experiencing TIA could assist in stroke prevention by indicating those at high risk of stroke who would benefit most from intervention for other stroke risk factors. The objective of this study was to investigate whether answers to a simple questionnaire for TIA could predict the occurrence of stroke in the following 20 years.

DESIGN

Prospective cohort study, conducted between 1972 and 1976, with 20 years of follow up.

SETTING

Renfrew and Paisley, Scotland.

PARTICIPANTS

7052 men and 8354 women aged 45-64 years at the time of screening completed a questionnaire and attended a physical examination. The questionnaire asked participants if they had ever, without warning, suddenly lost the power of an arm, suddenly lost the power of a leg, suddenly been unable to speak properly or suddenly lost consciousness. These four questions were taken as indicators of TIA and were related to subsequent stroke mortality or hospital admission.

MAIN RESULTS

For women, each question was significantly related to stroke risk, whereas for men only the question on loss of power of arm was significantly related to stroke risk. Men and women answering two or more questions positively had double the relative rate of stroke compared with men and women answering none of the questions positively, even after adjusting for other risk factors for stroke.

CONCLUSIONS

A simple questionnaire for TIA could help predict stroke over 20 years of follow up. Targeting men and women who report TIA with early treatment could help to prevent strokes from occurring.

HMG-CoA reductase inhibitor therapy and stroke risk reduction: an analysis of clinical trials data

Although associations of cholesterol and coronary heart disease (CHD) are well accepted, the association between cholesterol and stroke has been a subject of some confusion. Epidemiologic evidence suggests no association between plasma concentrations of cholesterol and stroke, and earlier clinical trials were also negative. Two early meta-analyses of clinical trials designed to evaluate the effects of cholesterol lowering on CHD concluded that cholesterol lowering had no effect. More recently newer, more potent and better tolerated agents (HMG-CoA reductase inhibitors, reductase inhibitors) have become available and have been tested for their efficacy in reducing cholesterol and CHD in both primary prevention and secondary prevention trials. Meta-analyses of these trials, in contrast to the earlier trials, reveal a powerful statistically significant effect to reduce stroke as well as CHD in secondary prevention (30%); the direction of the effect is the same in trials of primary prevention or trials that randomized patients with and without CHD (mixed primary and secondary prevention trials) where the risk reductions for stroke, although not reaching statistical significance are 11 and 30%, respectively. An important difference in the newer analysis is the availability of several trials of secondary prevention in which low density lipoprotein cholesterol was lowered 25-30% and in which CHD event reduction was similarly reduced by 30%. Mechanisms for stroke reduction likely involve retardation of plaque progression in the intracranial and extracranial carotid arteries, plaque stabilization, and, in addition, stroke may be reduced partly as a consequence of CHD reduction.

Prospective study of vascular events and cerebral perfusional changes following transient ischemic attacks

A prospective case-control study was carried out to clarify associations of cerebral transient ischemic attacks (TIAs) and other stroke risk factors with progression and exacerbation of cardiovascular and cerebrovascular disorders; 243 neurologically normal controls and 123 TIA patients without prior history of stroke were followed up for a mean interval of 4.4 years of TIA patients, 26 (21%) developed other events (excluding recurrent TIAs); 10 died of vascular causes (8.1%). Of controls, 44 (18%) developed events; 13 died of vascular causes (5.4%) and 3 from cancer. TIA patients were at 2.3 times greater risk than normal controls for stroke or death from vascular causes. They were predominantly male with significantly higher associations of risk factors for stroke, including hypertension, heart disease, diabetes mellitus, smoking, hyperlipidemia, alcohol consumption, and limited education. Controls developing vascular events compared with controls who did not were older, more frequently male, and with greater incidences of heart disease. TIA patients had lower rates of cerebral perfusion compared with controls that persisted throughout the study, with similar rates of decline related to aging among both groups. Among TIA patients, stroke risk factors were more prevalent than among controls. The longer their duration, the greater the incidence and the more rapid the rate of severe, often fatal cardiovascular complications.