Nerve conduction studies in healthy Chinese: correlation with age, sex, height and skin temperature

We consecutively collected 68 normal subjects who assented to receive electrophysiological examination in four limbs. There were 50 men and 18 women, with a mean age of 50.8 +/- 17.9 years (range: 15-88) and a mean height of 162.72 +/- 9.05 cm (range: 138-180). Mean skin temperature was 32.75 +/- 1.51 degrees C (range: 29.4-35.6) at wrist and 30.9 +/- 1.1 degrees C (range: 29-33) at lower leg. The mean values with standard deviation of the nerve conduction parameters such as distal latency, nerve conduction velocity, amplitude, duration and area of compound muscle action potential and sensory action potential, minimal latencies of H reflexes and F responses, and their side-to-side differences were presented. Age was negatively correlated with motor nerve conduction velocity (P < 0.05, r = -0.37 to -0.46), amplitude of compound muscle action potential (P < 0.05, r = -0.32 to -0.43) and sensory action potential (P < 0.05, r = -0.33 to -0.65), but not with sensory nerve conduction velocity (P > 0.05). Height was correlated with minimal latencies of H-reflexes and F-responses (P < 0.05, r = 0.45 to 0.76). Gender and temperature were not correlated with any parameters (P > 0.05).