Short-Term Prognosis of Transient Ischemic Attack and Predictive Value of the ABCD(2) Score in Hong Kong Chinese.
BACKGROUND
Literature on prognosis of transient ischemic attack (TIA) in Chinese is scarce. The short-term prognosis of TIA and the predictive value of the ABCD(2) score in Hong Kong Chinese patients attending the emergency department (ED) were studied to provide reference for TIA patient management in our ED.


METHODS
A cohort of TIA patients admitted through the ED to 13 acute public hospitals in 2006 was recruited through the centralized electronic database by the Hong Kong Hospital Authority (HA). All inpatients were e-coded by the HA according to the International Classification of Diseases, Ninth Revision (ICD9). Electronic records and hard copies were studied up to 90 days after a TIA. The stroke risk of a separate TIA cohort diagnosed by the ED was compared.


RESULTS
In the 1,000 recruited patients, the stroke risk after a TIA at days 2, 7, 30, and 90 was 0.2, 1.4, 2.9, and 4.4%, respectively. Antiplatelet agents were prescribed in 89%, warfarin in 6.9%, statin in 28.6%, antihypertensives in 39.3%, and antidiabetics in 11.9% of patients after hospitalization. Before the index TIA, the prescribed medications were 27.6, 3.7, 11.3, 27.1, and 9.7%, respectively. The accuracy of the ABCD(2) score in predicting stroke risk was 0.607 at 7 days, 0.607 at 30 days, and 0.574 at 90 days. At 30 days, the p for trend across ABCD(2) score levels was 0.038 (OR for every score point = 1.36, p = 0.040). Diabetes mellitus, previous stroke and carotid bruit were associated with stroke within 90 days (p = 0.038, 0.045, 0.030, respectively). A total of 45.4% of CTs of the brain showed lacunar infarcts or small vessel disease. There was an increased stroke risk at 90 days in patients with old or new infarcts on CT or MRI. Patients with carotid stenosis ≥70% had an increased stroke risk within 30 (OR = 6.335, p = 0.013) and 90 days (OR = 3.623, p = 0.050). Stroke risks at days 2, 7, 30, and 90 in the 289 TIA patients diagnosed by the ED were 0.35, 2.4, 5.2, and 6.2%, respectively.


CONCLUSIONS
The short-term stroke risk in Hong Kong Chinese TIA patients is low. The administered nonurgent treatment cannot solely explain the favorable outcome, the lower risk can be due to the different pathophysiological mechanisms of stroke between Caucasians and Chinese. The predictive value of the ABCD(2) score is low in our population.
Accident and Emergency Department at Princess Margret Hospital, Hong Kong, SAR, PR China.
Lai Hong Simon
LH
Chiu
Accident and Emergency Department at Queen Elizabeth Hospital, Hong Kong, SAR, PR China.
Wah Hon
WH
Yau
Accident and Emergency Department at Queen Mary Hospital, Hong Kong, SAR, PR China.
Ling Pong
LP
Leung
Accident and Emergency Department at Yan Chai Hospital, Hong Kong, SAR, PR China.
Peter
P
Pang
Accident and Emergency Department at Princess Margret Hospital, Hong Kong, SAR, PR China.
Chee Tat
CT
Tsui
Accident and Emergency Department at Ruttongie and Tang Siu Kin Hospital, Hong Kong, SAR, PR China.
Kuang An
KA
Wan
Accident and Emergency Department at Pamela Youde Nethersole Eastern Hospital, Hong Kong, SAR, PR China.
Thomas Tak-Shun
TT
Au
Department of Medicine and Geriatrics, Queen Elizabeth Hospital, Hong Kong, SAR, PR China.
Wing Chi
WC
Fong
Accident and Emergency Department at Tuen Mun Hospital, Queen Elizabeth Hospital, Hong Kong, SAR, PR China.
Shun Hang Joseph
SH
Chung
Carotid stenosis; Chinese ethnicity; Lacunar infarct; Prognosis; Stroke; Transient ischemic attack