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％),nomal 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 longterm outcome of the vascular events [HR =0.40,95 ％ CI 0.29-0.72,P =0.00].Conclusions The ratio of platetet 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.

Objective To investigate aspirin resistance (AR) and its related factors in patients with stage 3-4 chronic kidney disease(CKD).Methods The clinical data of 108 patients with stage 3-4CKD from nephrology department in Beijing Chaoyang Hospital were collected (CKD group) ; and 110 age and sex-matched subjects with normal renal function served as control group.Anthropometric parameters,blood biochemistry index,ultrasonography and thromboelastograph (TEG) were examined in both groups; and inhibition ratio of arachidonic acid ＞ 50％ on TEG was defined as AR.Results The incidence of cardio-cerebral vascular disease,the incidence of peripheral vascular disease,ratio of female,the intimamedia thickness (IMT) of carotid artery,the levels of high-sensitive C-reactive protein (hsCRP),homocysteine(Hcy),evaluated glomerular filtration rate(eGFR) and maximal thrombelastodegree (MA) on TEG in CKD group were significantly higher than those in control group (all P ＜ 0.05),while R value was significantly lower in CKD group.Pearson's correlation analysis revealed that the levels of MA,hsCRP,Hcy,IMT were positively correlated and R value was negatively correlated with eGFR in CKD group.The incidence of AR in CKD group (32.4％) was significantly higher than in control group (20.0％).According to TEG,the patients were divided into AR group (n =35) and aspirin sensitive (AS) group (n =73).The incidence of cardio-cerebral vascular disease,the incidence of peripheral vascular disease,ratio of female,IMT,ratio of diabetes,the levels of hsCRP,Hcy,fasting plasma glucose (FBG),eGFR and MA in AR group were significantly higher than those in AS group (all P ＜ 0.05),while R value was significantly lower in AR group.Binary logistic regressive analysis revealed that the ratio of diabete,FBG,eGFR,hsCRP were independent risk factors for AR in patients with stage 3-4 CKD.Conclusions CKD stage 3-4 is associated with increased ratio of platelet activation and atherosclerosis,and this condition is aggravated while eGFR declining.Incidence of AR is 32.4％ in this group of CKD patients,the independent risk factors of AR in CKD patients are the ratio of diabetes,FBG,eGFR and hsCRP.

Objective To elucidate the effect of bioimpedance ratio in the calf (calf-RBI) for volume evaluation on hypertension in hemodialysis (HD) patients. Methods Bioimpedance in the right calf was measured by bioimpedance spectroscopy (BIS). As an index of volume status, calf-RBI was calculated as follows: calf-RBI =impedance at 200 kHz / impedance at 5 kHz. The range of age-stratified 1SD from mean calf-RBI in the healthy control was assumed as the target range for the corresponding HD patients. The dry body weight (DBW) was stepwise decreased under the guidance of calf-RBI. The changes of calf-RBI, blood pressure and antihypertensive medications were recorded and correlation analysis among indexes was performed. Results The calf-RBI showed a normal distribution in both healthy subjects and HD patients. The calf-RBI was positively correlated with age, but not with gender or BMI. Forty-two patients with (35.9%) calf-RBI beyond target range were identified in 117 HD patients. The percentage of uncontrolled hypertensive individuals was significantly higher as compared to those with calf-RBI within or below target range (59.5% vs 33.3% and 16.7%, P＜0.01). The percentage of uncontrolled hypertensive individuals and the dose of antihypertensive medications was significant improved after decreasing the DBW in the patients with calf-RBI beyond target range (74.1% vs 33.3%, P＜0.01) and defined daily dose (2.00±2.28 vs 2.49±2.47, P＜0.05 ). Conclusions The age-stratified calf-RBI may be used as a useful index for estimation of volume status, and has a good association with clinical manifestations. Recognition and correction of chronic fluid overload based on age-stratified calf-RBI is helpful in hypertension control for hemodialysis patients.