Effect Of Plasma Homocysteine And Cystatin C On Type 2 Diabetic Peripheral Neuropathy

Objiective:To measure levels of plasma homocysteine (Hcy) and cystatin C(CysC) in phages of impaired glucose regulation, simple type 2 diabetes and diabetic peripheral neuropathy,analyze their correlations between Hcy and CysC, nerve conductive velocity, nerve reflex latency,age,sex,body mass index,course of disease,creatinine,fibrinogen,blood pressure,blood fat; and to investigate effect of plasma Hcy and CysC on diabetic peripheral neuropathy.Methods:According to subjective symptoms and electromyographic recorder,103 type 2 diabetic patients were divided into simple diabetic group (SDM), sub-clinical neuropathic group(SDPN), clinical neuropathic group (DPN).30 normal control (NC)and 30 impaired glucose regulation(IGR) subjects were admitted. Sex, age, height, body weight, blood pressure were recorded in all subjects.Fasting plasma Hcy, CysC, blood glucose, HbAlc, blood fat, serum creatinine and fibrinogen were measured in all cases. The correlations between Hcy and other parameters were analyzed. All parameters were compared among different groups.The correlations between Hcy and other parameters were analyzed.Results:1.In NC, IGR, SDM, SDPN, DPN groups, plasma Hcy levels were (6.00±1.43)μmol/L,(7.21±1.64)μmol/L,(8.21±2.40)μmol/L,(12.48±4.15)μmol/L,(13.51±5.80)μmol/L,respectively. In SDM, SDPN,DPN groups it was higher than it in NC and IGR groups(P< 0.05),but there was no significant difference between NC and IGR groups or SDPN and DPN groups. 2.1n NC, IGR, SDM, SDPN, DPN groups,the cases of hyperhomocysteinemia (Hcy≥15.μmol/L) were 0,0,1,4,8, respectively,and the frequency of hyperhomocysteinemia was 0,0,3.13%,11.42%,22.22%, respectively.There were significant differences in diabetic groups (all P< 0.01).According to NSS, There existed 16 mild cases,12 medius cases,8 severe cases in DPN group, plasma Hcy levels were (12.35±3.04)μmol/L, (13.32±5.07)μmol/L, (16.09±9.85)μmol／L in the three subgroups, but there were no significant differences among subgroups.3. In NC, IGR, SDM, SDPN, DPN groups, plasma CysC levels were (0.60 +0.14) mg/L, (0.63±0.17) mg/L, (0.81±0.26) mg/L, (1.01±0.29) mg/L, (1.23 +0.41) mg/L,respectively. There existed significant differences among groups (all P<0.01) except between NC and IGR groups (P=0.761).4.Pearson correlated analysis showed that plasma Hcy was negtively correlated with all nerve conductive velocity (r-0.283,-0.350,-0.621,-0.449, respectively,all P < 0.05),but positively correlated with latency periods of nervous reflex (r 0.409, 0.466,respectively,all P< 0.05), BMI (r=0.424, P=0.009), duration of diabetes(r =0.382, P=0.041), Cr(r=0.383, P=0.007), CysC(r=0.648, P=0.001) and FIB(r =0.342,P=0.038).5.In multivariant stepwise regression analysis model,after control BMI, duration of diabetes, Cr, FIB, CysC remained relationship with Hcy.Conclusion:1. Type 2 diabetes, with or without peripheral neuropathy, their fasting plasma Hcy concentrations were higher than those in NC and IGR groups. It suggestted that insulin resistance or insulin deficiency was related to Hcy metabolic disorders.Though IGR group had elevated plasma glucose and triglyceride levels, its Hcy was no significant difference compared to it in NC group, and did not find hyperhomocysteinemia. Whether related to the degree of insulin resistance, abnormal glucose and lipid metabolism, yet to be further explored.2. Nerve reflex latencies, motor and sensory nerve conduction velocity were slower in SDPN and DPN groups, and EMG-related parameters were related to plasma Hcy,which suggested that plasma Hcy was associated with nerve conduction abnormalities and may be regarded as a predictor of DPN.3. All patients with type 2 diabetes whose fasting plasma CysC concentrations were higher than those in NC and IGR groups, and they were associated with Hcy levels, which suggesting that CysC would probably aggravate DPN interacted with CysC.