[The incidence of aspirin resistance and relevant influencing factors in patients on maintenance hemodialysis].
OBJECTIVE
To explore aspirin resistance (AR) and its relevant influencing factors in patients on maintenance hemodialysis (MHD).


METHODS
Patients on MHD who visited Beijing Chaoyang Hospital from June 1 to 30, 2011 were enrolled in this study. A total of 150 age and gender matched individuals with normal renal function were taken as control group. Anthropometric data, biochemistry parameters, ultrasonography and thromboelastograph (TEG) were inspected in the both groups. AR was defined as inhibiting rate of acetylsalicylic acid drugs [MA(AA)]>50% by TEG.


RESULTS
Among the total 391 patients on MHD, hypercoagulation was found in 18 patients (4.6%), normal coagulation in 288 patients (73.7%) and hypocoagulation in 85 patients (21.7%). Pearson's correlation analysis revealed that the reaction time (R) and the thrombus maxithrombelastic degree (MA) values were not correlated with the levels of hemoglobin and platelet in MHD patients. A total of 306 patients with hypercoagulation and normal coagulation were chosen as the MHD group. Compared with the control group, higher high sensitivity C reactive protein (hsCRP), homocysteine (Hcy) and R value were observed in the MHD group (P < 0.05), while MA was significantly lower in the MHD group. Statistically higher incidence of AR was shown in the MHD group (48.0% vs 20.0%, P = 0.00). Patients in the MHD group were divided into the AR group and the aspirin sensitive (AS) group by the result of TEG. Compared with the AS group, patients in the AR group were found to be older with a higher female/male ratio, longer dialysis sustained time, higher ratio of diabetes history, higher hsCRP, Hcy and fasting blood glucose (FBG) and MA. They also manifested a higher incidence of cardiovascular and cerebrovascular diseases, peripheral vascular disease and arteriovenous fistulas with thrombosis with more spots of carotid artery and higher intima thickness of carotid artery (IMT) (all P values<0.05). Lower R value was shown in the AR group. Binary logistic regressive analysis revealed that the ratio of diabetes history, age and dialysis sustained time. Hcy and hsCRP were the independent risk factors for AR in patients on MHD. A total of 289 patients on MHD with atherosclerosis were followed up for the mean time of 18.0 months with no hemorrhage found in the process. Cox proportional hazards regression modeling demonstrated that AR was associated with the major adverse long-term outcome of the vascular events [HR = 0.40, 95%CI 0.29-0.72, P = 0.00].


CONCLUSIONS
The ratio of platelet activation in patients on MHD is significantly lower than in those with normal renal function. Small dose of aspirin could be prescribed for the patients on MHD with atherosclerosis to prevent vascular events. The incidence of AR is 48.0% in the MHD group and the independent risk factors for AR in MHD patients are the ratio of diabetes history, age, dialysis sustained time, Hcy and hsCRP. AR is associated with the major adverse long-term outcome of acute vascular events.
Urology and Nephrology Center, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
Chunhua
C
Zhang
Urology and Nephrology Center, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China. Email: andrewcui@sina.com.
Taigen
T
Cui
Urology and Nephrology Center, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
Sumei
S
Zhao
Urology and Nephrology Center, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
Shixiang
S
Wang
Urology and Nephrology Center, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
Xiaodong
X
Zhang
D000368:Aged; D001241:Aspirin / Q000494:pharmacology*; D016022:Case-Control Studies; D004351:Drug Resistance; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis / Q000009:adverse effects*; D012307:Risk Factors
D001241:Aspirin