healthmedicinet

Subjects

A hospital-based retrospective study was performed from January 1, 2006 to December
31, 2006. During this period, a total of 1377 consecutive stroke patients were admitted
to the Department of Neurology, the Second Affiliated Hospital of Guangzhou Medical
University. Five hundred and thirty patients with acute ischemic stroke (within 7 days
from symptom onset) were eligible to be recruited in this study (Fig. 1). Criteria for exclusions were patients who experienced the onset of stroke more
than 7 days before hospitalization, or who were diagnosed with “silent stroke” or
who were sent to the Emergency Department and died soon there before hospitalization.
Patients with cerebral hemorrhage, subarachnoid hemorrhage, brain tumor or other central
nervous system disorders were also excluded. This study was approved by the Hospital
Institutional Ethics Committee. Also, written informed consent to participate in the
study was obtained from each patient or his/her relative if patients could not consent
by themselves.

Fig. 1. Study design

All the subjects presented clinical characteristics of acute ischemic stroke, confirmed
by cranial computed tomography and/or magnetic resonance imaging/angiography.

Assessments

Data collection was performed by using a standardized questionnaire based on an extensive
manual and follow-up information. General information, present illness, previous history
(including hypertension, diabetes mellitus, coronary heart disease, transient ischemic
attack and stroke), personal history (including cigarette smoking and drinking habits),
family history (including hypertension, diabetes mellitus, coronary heart diseases
and cerebrovascular diseases), the data of physical examination, laboratory and imaging
results were all recorded for all subjects enrolled in this study. Carotid ultrasonography,
transcranial doppler and magnetic resonance angiography were used to evaluate brain-supplying
arteries. Cardiac diagnostic test such as electrocardiography and transthoracic echocardiography
were used to identify cardioembolic stroke.

All the baseline clinical characteristics were recorded at the time of admission while
venous blood samples were extracted after 12 h fasting time at the second day of hospitalization.
Serum glucose, TG, TC, HDL-C, LDL-C, apolipoprotein (Apo)-A, Apo-B, creatinine, urea
nitrogen and UA were measured by Hitachi 7600 automatic analyzer (Hitachi Instruments
Corporation, Tokyo, Japan). Blood fibrinogen was evaluated by turbidimetry with the
use of CA7000 (Sysmex, Japan).

Waist circumference was measured by a measuring tape positioned at the narrowest part
between the lowest rib margin and the high point of the iliac crest after a normal
expiratory breath. Body height was measured, without wearing shoes, with an accuracy
of 0.1 cm, using a calibrated stadiometer. Body weight was measured to the nearest
0.1 kg, wearing underwear, with a calibrated electronic scale. BMI was calculated
by dividing weight by height squared (kg/m
²
). Blood pressure was measured on the right arm at heart level with a mercury sphygmomanometer
after being seated for at least 5 min. CCAs IMT was defined as the distance between
the edges of the lumen-intima interface and the media-adventitia interface of the
far wall. In this study, IMT of both CCAs were uniformly measured by one sonographer,
using color doppler ultrasonography (ALOKA prosound ?5, Hitachi Instruments Corporation,
Tokyo, Japan) with a 7.5?~?10.0 MHz transducer frequency in 3 days after admission.

Clinical assessments consisted of the NIHSS, mRS and BI, which were performed by four
well-trained neurologists who were blinded to magnetic resonance imaging results.
The score of NIHSS is from 0 (normal) to 42, measured at the admission. Functional
outcome was assessed with mRS and BI at 30 and 90 days after the occurrence of stroke.
Patients who died scored 6 in the mRS. A mRS of 0 to 2, or a BI score of 95 to 100
was considered as a favorable outcome, and mRS ?3 or BI 60 was used as cutoff scores
to defined poor outcome 36].

Recurrent stroke was defined as any new episode of focal cerebral dysfunction persisting
24 h, which occurred after a period of unequivocal neurological stability or improvement.
This definition excluded any new deficit that occurred within 24 h or that was thought
to be attributable to edema, mass effect, brain shift syndrome, or hemorrhagic transformation
of the incident infarct.

Patients were followed up with hospital visits during the first and three months after
the stroke event. Patients who were unable to attend the scheduled visits or had migrated
from our city were contacted by telephone. In case of death, dates and causes were
registered by gathering information from relatives or records kept by hospitals.

Definition of metabolic syndrome

Patients were classified into two groups at baseline based on whether or not the diagnostic
criteria for MetS were met. According to the American Heart Association/National Heart,
Lung, and Blood Institute definition for MetS 37], MetS was defined as the presence of any three of the following five risk components:
(i) elevated WC (male???85 cm, female???80 cm), (ii) TG???1.70 mmol/L, (iii) HDL-C??1.0 mmol/L
(male) or 1.3 mmol/L (female), (iv) hypertension: systolic pressure???130 mmHg, diastolic
pressure???85 mmHg or need for anti-hypertensive medication and (v) hyperglycemia:
FBG???5.6 mmol/L (?100 mg/dL) or need for anti-hyperglycemic medication.

Statistical analysis

The data was entered duplicatedly into a stroke data bank built with Microsoft Visual
FoxPro 6.0 and checked for completeness, logical consistency and duplication, and
then locked in. Statistical analyses were performed with the Statistical Package for
Social Sciences for Windows, version 13.0 (SPSS, Inc, Chicago, IL, USA). Measurement
data were summarized by mean?±?standard deviation or as median and 25th and 75th quartile
values. The differences of baseline characteristics of the patients were compared
with the unpaired Student’s t-test or Mann-Whitney test for continuous variables and the chi-square test or Fisher’s
exact test for categorical variables. To generate the odds ratio, univariate binary
logistic regression analysis was conducted to assess MetS, hyperglycemia, hypertension,
low HDL-C, elevated TG and high WC to the contribution of stroke prognosis. Further,
multiple logistic regression models were conducted after adjusting for age and sex.