Nerve conduction and its correlations with duration of diabetes mellitus and glycosylated haemoglobin in type 2 diabetes mellitus (T2DM)

Background: Diabetic neuropathy is one of the most common microvascular complications associated with diabetes mellitus. Diabetic peripheral neuropathy (DPN) has been linked to hyperglycaemia and long duration of uncontrolled type 2 diabetes mellitus (T2DM) as measured by glycosylated haemoglobin (HbA1c). To our knowledge the estimated duration between diagnosis and developing DPN and the level of HbA1c have not yet been investigated in Sudanese patients with type 2 DM. Therefore, this study aims to investigate the relationship between the duration of diabetes and HbA1c with nerve conduction velocity (NCV) in patients with type 2 DM. Methods: This cross-sectional study recruited 63 male and female patients with T2DM who attended the diabetic outpatient clinic of Academy Charity Teaching Hospital (ACTH) and Alzaytouna Private Hospital for Nerve Conduction Velocity (NCV) and electromyography (EMG) tests. Nerve conduction was done by using ADInstruments PowerLab series 26. SPSS was used to analyse the data and p-value < 0.05 was considered significant. Results: The mean duration of DM was 14.7 (± SD 9.24) years and the mean age of participants was 57.71 (± SD 12.2) years. The most common symptom was numbness (50%). Pearson's correlation test revealed a significant negative correlation between HbA1c and nerve conduction velocity (r = 0.4, p < 0.05) and negative significant correlation between the duration and the amplitude (r = 0.35, p < 0.05). Conclusion: There is a slowing of nerve conduction velocity in type 2 diabetic patients, which is accelerated by the poor glycaemic control (HbA1c). These findings support the need for tight glycaemic control to avoid drastic neuropathic complications of diabetes.