Risk of major vascular events in patients without traditional risk factors after transient ischemic attack or minor ischemic stroke: An international prospective cohort

Shinichiro Uchiyama; Takao Hoshino; Kazuo Minematsu; Marie-Laure Meledje; Hugo Charles; Gregory W Albers; Louis R Caplan; Geoffrey A Donnan; José M Ferro; Michael G Hennerici; Carlos Molina; Peter M Rothwell; Lawrence Ks Wong; Pierre Amarenco

doi:10.1177/23969873241300071

Risk of major vascular events in patients without traditional risk factors after transient ischemic attack or minor ischemic stroke: An international prospective cohort

Eur Stroke J. 2024 Nov 21:23969873241300071. doi: 10.1177/23969873241300071. Online ahead of print.

Authors

Affiliations

¹ Clinical Research Center for Medicine, International University of Health and Welfare, Department of Neurology, Akasaka Sanno Medical Center, Tokyo, Japan.
² Department of Neurology, Tokyo Women's Medical University, Tokyo, Japan.
³ National Cerebral and Cardiovascular Center, Osaka, Japan.
⁴ Department of Neurology and Stroke Center, Bichat Hospital, Paris, France.
⁵ Stanford Stroke Center, Department of Neurology and Neurological Sciences, Stanford University Medical Center, Stanford, CA, USA.
⁶ Cerebrovascular Disease Service, Beth Israel Deaconess Medical Center, Harvard University, Boston, MA, USA.
⁷ Melbourne Brain Centre, Royal Melbourne Hospital, University of Melbourne, Parkville, VIC, Australia.
⁸ Instituto de Medicina Molecular João Lobo Antunes, Universidade de Lisboa, Lisbon, Portugal.
⁹ Department of Neurology, Universitäts Medizin Mannheim, Heidelberg University, Heidelberg, Germany.
¹⁰ Department of Neurology, Stroke Unit, Vall d'Hebron University Hospital, Universitat Autonoma de Barcelona, Barcelona, Spain.
¹¹ Department of Clinical Neuroscience, Wolfson Centre for Prevention of Stroke and Dementia, University of Oxford, Oxford, UK.
¹² Department of Medicine and Therapeutics, Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong Special Administrative Region, China.

Abstract

Introduction: To investigate the clinical characteristics in patients without traditional risk factors (TRFs) after transient ischemic attack or minor ischemic stroke, who were recruited in the TIAregistry.org.

Patients and methods: A total of 3847 patients were analyzed. TRFs included hypertension, diabetes, hypercholesterolemia, current smoking, and atrial fibrillation. Background characteristics and outcomes at 1 and 5 years in patients without TRFs were compared to those in patients with TRFs. The primary outcome was major cardiovascular event (MACE), which was non-fatal stroke, non-fatal acute coronary syndrome, or vascular death. To evaluate the causes, we applied the ASCOD (atherosclerosis, small vessel disease, cardiac pathology, other causes or dissection) grading system.

Results: One-year risk of MACE (5.3% vs 6.3%, hazard ratio (HR) 0.84, 95% confidence interval (CI) 0.53-1.31) was comparable between patients without TRFs (n = 402) and those with TRFs (n = 3445). Five-year risk of MACE was significantly lower in patients without TRFs than in those with TRFs (7.9% vs 13.9%, HR 0.57, 95% CI 0.39-0.82). In patients without TRFs, causal atherosclerosis was a potent risk factor (HR 5.67, 95% CI 2.68-12.02) and ipsilateral extra- or intra-cranial arterial stenosis was only significant predictor of MACE (interaction p = 0.0046) at 5 years.

Conclusion and discussion: The 5-year risk of MACE was lower in patients without TRFs than those with TRFs, although a certain level of risk persisted in the absence of TRFs. The most significant predictor of MACE in patients without TRFs was arterial stenosis.

Keywords: Transient ischemic attack; arterial stenosis; prevention; risk factor; stroke.