Nerve conduction parameters and its correlations with glycemic control and duration in type 2 diabetes mellitus − A cross-sectional study

Background: Diabetic neuropathy is one of the most common microvascular complications of diabetes mellitus (DM) and can lead to a wide array of complications, which are concerning as these are considered a leading cause of disability due to foot ulceration, amputation, gait disturbances, and injuries secondary to falls. Nerve conduction studies (NCS) enable the diagnosis of sensory and motor neuropathy even if the dysfunction is subclinical. This study was conducted to assess the correlation between glycated hemoglobin and duration of diabetes with the parameters of NCS among patients of type 2 DM. Methodology: A cross-sectional study was conducted in a tertiary care center in South India. The study was conducted from November 2022 to February 2023. Sixty patients with type 2 DM who presented to the outpatient department with symptoms of neuropathy were included in the study. Detailed clinical history was taken and clinical examination was done. NCS was conducted in them. The parameters of NCS were correlated with HbA1c and duration of diabetes. The statistical analysis was carried out using the SPSS software version 29.0. Results: Sixty patients with type 2 DM were included in the study. The mean age of type 2 DM patients was 60.92 ± 10.9 years. The mean duration of type 2 DM (in years) was 12.8 ± 6.5. Twenty-three participants (38.3%) had solely an axonal pattern of diabetic neuropathy; whereas 20 (33.3%) participants showed a combined axonal and demyelinating pattern of diabetic neuropathy. There was a significant negative correlation between HbA1c and NCS parameters such as nerve conduction velocity, amplitude, and persistence ( p < 0.001); and a significant positive correlation between HbA1c and NCS parameters such as latency and F -wave latency ( p < 0.001). There was a significant correlation between parameters of NCSs and duration of DM ( p < 0.001). Conclusion: Glycemic control and duration of DM have a significant impact on the nerve conduction parameters. Patients with poor glycemic control have decreased NCS parameters such as velocity, amplitude, and persistence; and increased parameters such as latency and F -wave latency. Strict glycemic control can be reinforced for better management of diabetic neuropathy.