Methods
Study population
We collected data on 801 patients with type 2 diabetes suffering from
acute ischemic cardio-cerebral vascular events, including acute coronary
syndrome (ACS) and acute ischemic stroke (AIS), at the Guangdong
Provincial People’s Hospital and Guangdong Geriatrics Institute during
the past four years from the hospital information system(seen in Figure.
1). All enrolled patients must be within one week from onset to
admission, and were treated with
dual antiplatelet therapy (DAPT,
including clopidogrel (Plavix) and aspirin).
Exclusion criteria:
patients with atrial fibrillation, cerebral embolism, hemorrhagic
stroke, thrombocytopenia, thrombocytosis, platelet dysfunction, type 1
diabetes, coagulation dysfunction, severe liver disease, hematopoietic
dysfunction, chronic kidney disease (≥stage 3), pregnancy, or malignant
tumors and patients treated with anticoagulant agents or thrombolytic or
novel antiplatelet drugs within one week before admission. Patients with
partial clinical data or laboratory results were also excluded.
Data collection and
organization:
Data collection:
Staff employed in the statistics office of our hospital conducted a data
search based on important fields, such as diagnosis, laboratory results,
and primary clinical medications.
Data arrangement:
Data such as diagnosis, laboratory results, and clinical medications
were integrated into the same data file based on ”patient identification
number & hospitalization date” by Excel for Windows; thus, a medical
database was established.
Data elimination:
To avoid selective bias and confounding factors, we chose the data from
patients treated with a single hypoglycemic drug. Data with a small
sample, such as patients treated with short-acting insulin, dipeptidyl
peptidse-4 inhibitors, repaglinide, or thiazolidinedione, were
eliminated. Moreover, patients with insulin duration <7 days
were excluded, and for core data such as the maximum amplitude of
adenosine diphosphate-induced platelet-fibrin clots
(MAADP), the outliers were eliminated, the criteria
were -3 ≤ z ≤ 3.
These details are shown in Figure. 1.
Data supplementation:
We reviewed medical documents and supplied some demographic data
(height, weight, etc.), lifestyle data (smoking, drinking, etc.), and
data on past medical history and drugs taken before admission. For those
who did not have a detailed record, we contacted the patient by phone.
Data verification:
All core data were carefully verified by 2 staff members.
Antiplatelet therapy
regimen:
According to clinical record data, all patients included presented two
groups, Conventional DAPT (clopidogrel 75 mg daily, aspirin 100 mg
daily) should be carried out at least 7 days before admission. For those
who did not take any antiplatelet drugs before admission or only took
one antiplatelet drug, they received intensive DAPT (clopidogrel 300 mg
daily, aspirin 300 mg daily) after admission. The clopidogrel taken by
patients was a reference listed drug, not a generic drug.
CYP2C19 Genotyping
As stated in the published article, 14 CYP2C19 was
determined in our hospital by a genotyping kit (DNA Microarray, BaiO
Inc., Shanghai, China).CYP2C19*2 mutations include 681GA and 681AA,
while CYP2C19*3 mutations include 636GA and 636AA.
Thromboelastography (TEG)
Thrombelastograms (TEGs) reflects not only thrombin generation kinetics
and fibrinnetwork formation during clot generation but also platelet
function.15 MAADP refers to the
maximum fibrin clot strength induced by adenosine diphosphate(ADP), and
is an important indicator in TEG. The quantitative assessment of
MAADP measured by TEG can assess the patient’s response
to oral antiplatelet therapy and can be related to the prognosis of
cardiovascular and cerebrovascular events,15-17 and
with the increase of MAADP, the risk of thrombosis
increased or the antiplatelet effect was poor.18 In
the study, we adopted MAADP measured by TEG as a main
indicator to evaluate patients’ effect on antiplatelet treatment.
Blood samples that were collected from patients at least 6 h after they
received intensive treatment or 7 days after they received regular
antiplatelet therapy were sent for analysis in vacutainer tubes
containing 3.2% trisodium citrate. The vacutainer tubes were filled to
capacity and inverted 3–5 times to ensure complete mixing of the
anticoagulant. Thrombelastography® uses four channels to detect the
effects of antiplatelet therapy acting via the arachidonic acid and ADP
pathways. A detailed description of this method has been outlined
previously.19 The TEG® 5000 Thrombelastograph®
Hemostasis Analyzer System (Haemoscope Corporation, Niles, USA) and
automated analytical software were used to measure the physical
properties.
Statistical Analysis
Statistical analysis was performed using IBM SPSS Statistics 23
software. The Kolmogorov-Smirnov test (KS test) was used to perform
normal distribution analysis for all measurement data. Data that were
fit for analyses were transferred to the normal distribution. Continuity
variables are expressed as the mean ± the standard deviation (SD). Each
candidate risk factor was analyzed by univariate linear regression
analysis, and P < 0.1 was defined as the screening
criterion. Then,
stratified
regression analysis was carried out to gradually adjust for the
demographic data, genetic factors, lifestyle, biochemical indicators,
antiplatelet regimen, etc., and to analyze the effects of hypoglycemic
treatment on MAADP tested by TEG. p <
0.05 was defined as statistically significant.
The present study was approved by the Human Ethics Committee of
Guangdong Provincial People’s Hospital and Guangdong Academy of Medical
Sciences (No. GDREC2017280H) and adhered to the tenets of the
Declaration of Helsinki.