Electrophysiological Characteristics Of Impaired Glucose Regulation Combined With Peripheral Neuropathy

Objective:Using nerve conduction study(NCS)to explore the characteristics of nerve damage in patients with impaired glucose regulation(IGR)combined with peripheral neuropathy(PN)and understand the relationship between impaired glucose regulation and Large fiber neuropathy,evaluate the diagnostic value of NCS combined with Toronto clinical scoring system(TCSS)for IGR combined with PN,help clinicians to detect peripheral neuropathy in patients with impaired glucose regulation earlyMethods:There were a total of 150 subjects in the experimental groups,including 50 patients with IFG,50 patients with IGT and 50 patients with type 2 diabetes,all subjects scored no less than 6 in the Toronto clinical scoring system.They were divided into three groups,namely IFG+PN group,IGT+PN group and DPN group.At the same time,50 healthy subjects were selected as the control group.The motor nerve conduction study was performed on median nerve,ulnar nerve,tibial nerve,and common peroneal nerve of limbs on one side of all subjects.The measurement indicators included motor nerve conduction velocity(MCV),compound muscle action potential(CMAP),and distal motor latency(DML).Sensory nerve conduction study was performed on median nerve,ulnar nerve,sural nerve,and superficial peroneal nerve of the subjects.The measurement indicators included sensory nerve conduction velocity(SCV)and sensory nerve action potential(SNAP).The F-wave mean latency and occurrence in ulnar nerve and tibial nerve were measured.Blood lipids and HbAlc levels were measured by standard laboratory methods in all subjects All the data were statistically analyzed by SPSSResults:(1)The levels of glycated hemoglobin,triglycerides and low-density lipoprotein(LDL)were significantly higher in patients with impaired glucose regulation combined with peripheral neuropathy and patients with DPN compared with healthy subjects(P<0.05).There was no significant difference in the levels of total cholesterol and high-density lipoprotein(HDL)between the patients with impaired glucose regulation combined with peripheral neuropathy and the healthy subjects(P>0.05).Level of HDL of patients with DPN was lower than healthy subjects(P<0.05)(2)Sensory nerve conduction study:The SNAP amplitude and SCV of median nerve in the experimental groups were lower than the control group(P<0.05).The SNAP amplitude and SCV of median nerve in DPN group were lower than the other three groups,and were below the lower limit of normal value.In addition,a considerable number of patients in the DPN group had carpal tunnel syndrome.The SNAP amplitude of sural nerve and superficial sural nerve in the experimental groups was significantly lower than the control group(P<0.05).Compared with the control group,the SCV of the sural nerve and superficial peroneal nerve in IGT+PN group and DPN group was significantly reduced(P<0.05).There was no significant difference in SCV of the sural nerve and superficial peroneal nerve between IFG+PN group and control group(P>0.05).The SNAP amplitude and SCV of median nerve,sural nerve and superficial peroneal nerve in DPN group were significantly lower than the IFG+PN group(P<0.05).There was no significant difference in SCV and SNAP amplitude between the four groups(P>0.05)(3)Motor nerve conduction study:the MCV and CMAP amplitude of the median nerve,common peroneal nerve,and tibial nervewere significantly reduced,DML was prolonged in DPN group when compared with the control group(P<0.05).When compared with the contrast group,the CMAP amplitude of the median nerve,common peroneal nerve and tibial nerve was significantly reduced,DML was prolonged,and MCV of the median nerve,common peroneal was decreased in IGT+PN group(P<0.05).In comparison with control group,the MCV of median nerve and the CMAP amplitude of tibial nerve were significantly reduced in IFG+PN group(P<0.05).In comparison with IFG+PN group,the CMAP amplitude of median nerve and common peroneal nerve was significantly reduced,DML was prolonged,and MCV of the tibial nerve was decreased in DPN group(P<0.05).The CMAP amplitude of common peroneal nerve was significantly reduced,DML was prolonged in IGT+PN group when compared with IFG+PN group(P<0.05)(4)There were statistical difference in the F-wave mean latency and occurence in ulnar nerve and tibial nerve between experimental groups and control group(P<0.05).The F-wave occurence in ulnar nerve and tibial nerve was reduced and the F-wave mean latency in tibial nerve was prolonged in DPN group.The F-wave occurence in tibial nerve was reduced in IGT+PN group.The F-wave mean latency in tibial nerve was prolonged in DPN group and in comparison with IFG+PN group and IGT+PN group,the difference was significant(P<0.05).The F-wave mean latency in tibial nerve was prolonged in IGT+PN group when compared with IFG+PN group(P<0.05)There were statistical difference in the F-wave mean latency and occurence in ulnar nerve and tibial nerve between IFG+PN group and DPN group(P<0.05)Conclusions:(1)Patients with impaired glucose regulation and peripheral neuropathy are prone to abnormal lipid metabolism,which is similarto DPN patients,mainly manifested as an increase in triglycerides and low-density lipoprotein(2)Injury of large nerve fibers are found in patients with impaired glucose regulation and PN,lower extremity nerves are more influenced than upper extremity nerves,which are reflected in the decrease of SNAP amplitude and SCV of sural nerve and superficial peroneal nerve.Sensory nerves are more affected than motor nerves(3)According to the Toronto Clinical Scoring System,the degree of nerve damage is the least in IFG patients with PN(7.48±2.22),followed by IGT patients with PN(10.32±2.29),and patients with DPN(12.16±2.46)(4)F-wave detection showed that the damage of proximal nerve in patients with impaired glucose regulation may be earlier than that of distal nerve,and the injury of tibial nerve is more commonly than ulnar nerve.