Impact of impaired glucose regulation on the functions of large and small fibers of peripheral nerves

Na Liu,Ju Zhu,Zhecheng Zhang,Qian Li,Jing Zhang,Xianzhu Zeng,Li Tian

doi:10.3906/sag-1804-53

Abstract

This article analyzes the incidence and characteristics of peripheral neuropathy in patients with impaired glucose regulation (IGR). A total of 120 IGR patients and 60 healthy controls were enrolled. All subjects underwent nerve conduction study (NCS) of large fibers and skin sympathetic response (SSR) and contact heat pain evoked potential (CHEP) testing of small fibers with a Medtronic Keypoint machine (Medoc Ltd., Israel). IGR patients were evaluated using the Michigan Neuropathy Screening Instrument (MNSI). The abnormal rates (MNSI >2) in IGR patients and NCS and SSR evaluations were 18.3%, 22.5%, and 39.2%, respectively. All abnormal NCS findings were accompanied with abnormal SSR findings. Compared with the control group, the sensory nerve action potential wave of the posterior tibial and sural nerve was decreased in the IGR group (P = 0.01, P = 0.00), the SSR wave was reduced in the upper and lower limbs (P = 0.002, P = 0.00), and the CHEP wave was decreased in opisthenar and shank (P = 0.00). Compared with the control group, the CHEP wave was decreased in the shank in the normal SSR group (P < 0.05) and in the opisthenar and shank in the normal NCS group (P < 0.05). IGR patients have peripheral neuropathy characterized by impaired functions of large and small fibers focused on small fiber and lower limb sensory nerves. CHEP can detect small fiber damage earlier than SSR and NCS.

Highlights

Impaired glucose regulation (IGR), known as prediabetes, is defined as the intermediate stage that is higher than the normal value of blood glucose but lower than the diabetes threshold
Compared with the control group, the sensory nerve action potential wave of the posterior tibial and sural nerve was decreased in the IGR group (P = 0.01, P = 0.00), the skin sympathetic response (SSR) wave was reduced in the upper and lower limbs (P = 0.002, P = 0.00), and the contact heat pain evoked potential (CHEP) wave was decreased in opisthenar and shank (P = 0.00)
Conclusion: : IGR patients have peripheral neuropathy characterized by impaired functions of large and small fibers focused on small fiber and lower limb sensory nerves

Summary

Introduction

Impaired glucose regulation (IGR), known as prediabetes, is defined as the intermediate stage that is higher than the normal value of blood glucose but lower than the diabetes threshold. IGR consisted of impaired fasting glucose (IFG) and impaired glucose tolerance (IGT), and 5%–10% IGR patients may develop diabetes mellitus (DM) per year. According to a report by the International Diabetes Federation, it is predicted that the number of global IGR patients will reach 471 million by 2035 [1]. In China, the IGR population reached 148.2 million in 2010 [2]. Peripheral neuropathy (PN) is one of the three most prevalent complications of DM and 10% of patients diagnosed with DM had accompanying PN [3]. Several researchers have already demonstrated that IGT patients have

Methods

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Conclusion