Original article / research
Year : 2026 Month : July Volume : 15 Issue : 3 Page : BO01 - BO06 Full Version

Association of HbA1c with Oxidative Stress and Peripheral Neuropathy in Newly Diagnosed Type 2 Diabetes Mellitus Cases: A Cross-sectional Study
Shreoshi Kayal, Joyashree Banerjee, Ankita Rana, Bulbul Mukhopadhyay
1. Junior Resident, Department of Physiology, R. G. Kar Medical College and Hospital, Kolkata, West Bengal, India. 2. Professor and Head, Department of Physiology, Tamrolipta Govermnent Medical College and Hospital, Kolkata, West Bengal, India. 3. Junior Resident, Department of Physiology, R. G. Kar Medical College and Hospital, Kolkata, West Bengal, India. 4. Professor, Department of Physiology, R. G. Kar Medical College and Hospital, Kolkata, West Bengal, India.
 
Correspondence Address :
Joyashree Banerjee,
Flat no 9E, Tower 2, The Forest, 24-Beerpara Lane, Kolkata-30, West Bengal, India.
E-mail: banerjeedrjoyashree@gmail.com
 
ABSTRACT
: Introduction: Diabetic neuropathies are the most common, yet least understood and recognised long-term complications of diabetes. With rising Glycated Haemoglobins (HbA1c) levels, nerve conduction velocities slow and amplitudes decrease, indicating ongoing damage to the myelin sheaths and axonal loss. Worsening glycaemic control leads to increased Oxidative Stress (OS), which has been proposed to play a significant role in the progression of Diabetic Peripheral Neuropathy (DPN).
Aim: To evaluate peripheral nerve damage and Oxidative Stress levels in newly diagnosed Type 2 Diabetes Mellitus (T2DM) patients using Nerve Conduction Studies (NCS) and to assess their association with HbA1c levels.

Materials and Methods: The present cross-sectional analytical study was conducted on 60 newly diagnosed T2DM patients aged 40-60 years and 60 non-diabetic controls in the Department of Physiology, RG Kar Medical College and Hospital, Kolkata, West Bengal, India, from February 2023 to January 2024. Motor NCS were performed on the bilateral ulnar, median, and posterior tibial nerves, and sensory NCS were conducted on the bilateral median and sural nerves. OS levels were assessed by measuring the antioxidant enzyme catalase using spectrophotometry. Blood samples were collected for estimation of catalase activity, Fasting Blood Sugar (FBS), Postprandial Blood Sugar (PPBS), and HbA1c. Statistical analyses included Pearson’s correlation coefficient and the unpaired t-test.

Results: Among the 60 patients (mean age 57 years; male:female ratio=1:1), 40% exhibited DPN. Distal motor latency of the bilateral median, ulnar, and tibial nerves was significantly increased in cases compared with controls. Motor nerve conduction velocity was significantly reduced in the patient group. Sensory nerve conduction velocity and sensory nerve action potential amplitudes of the bilateral sural nerves were decreased, while distal sensory latency was prolonged in cases compared with controls. A significant negative correlation was observed between HbA1c levels and catalase activity (r= -0.78, p<0.0001).

Conclusion: Newly diagnosed T2DM patients demonstrated significant abnormalities in nerve conduction parameters and a strong association between poor glycaemic control and OS. These findings suggest early nerve involvement and increased oxidative damage even at the time of diagnosis.
Keywords : Blood glucose, Catalase activity, Diabetic neuropathy, Glycated haemoglobins, Nerve conduction study, Sensory nerve latency
DOI and Others : DOI: 10.7860/NJLM/2026/81791.2972 Date of Submission: Jul 04, 2025 Date of Peer Review: Sep 19, 2025 Date of Acceptance: Jan 14, 2026 Date of Publishing: Jul 01, 2026 AUTHOR DECLARATION: • Financial or Other Competing Interests: None • Was Ethics Committee Approval obtained for this study? Yes • Was informed consent obtained from the subjects involved in the study? Yes • For any images presented appropriate consent has been obtained from the subjects. NA PLAGIARISM CHECKING METHODS: • Plagiarism X-checker: Jul 05, 2025 • Manual Googling: Jan 07, 2026 • iThenticate Software: Jan 12, 2026 (1%) ETYMOLOGY: Author Origin EMENDATIONS: 8
 
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