Effect of smoking on nerve conduction velocity in type 2 diabetes mellitus patients

Background: India has one of the highest prevalence of Diabetes mellitus globally. One of the leading micro-vascular complication of diabetes mellitus is diabetic neuropathy. Smoking is a huge public health problem in India and is known to affect blood supply of peripheral nerves. Hence, both smoking and diabetes mellitus can adversely affect the peripheral nervous system. Aim & Objectives: To study the effect of tobacco smoking on nerve conduction velocity in male patients with type 2 diabetes mellitus. Materials & methods: The study comprised of 3 groups with 25 individuals each. Group A – Non diabetic, non smoking healthy volunteers. Group B – Non smoking individuals with diabetes mellitus type 2. Group C - Individuals with diabetes mellitus type 2 who were smokers. Every individual in each of the group was subjected to right median nerve motor and sensory nerve conduction studies, right peroneal motor nerve conduction studies and right sural sensory nerve conduction studies, in accordance to established parameters. Results: Sural sensory NCV was significantly lower (P<0.05) in the diabetic smokers (group C) as compared to controls (group A) and diabetic non-smokers (group B). Median sensory NCV was significantly lower (P<0.05) in the diabetic smokers (group C) as compared to non-smokers (group B). Conclusion: In smokers with diabetes there is subclinical reduction in sensory nerve conduction velocities suggestive of earlier onset of peripheral diabetic neuropathy.