A study on median nerve conduction velocity in different age groups.

Background: Nerve Conduction Velocity (NCS) is a test to measure the speed and electrical activity in a nerve. Physiological factors like age, temperature, height, gender affect the nerve conduction velocity. There is paucity on the data regarding the age group at which these changes become significant. Therefore, the aim of the study was to determine the specific age group at which changes in nerve conduction velocity occurs. Methods: 103 individuals in the age group of 15-65 years participated in the study. They were grouped into, Group I in the age group of 15-30 (n=40) years, Group II 31-45 years (n=31), Group III 46-60 years (n=32). Median motor and sensory conduction velocity were determined. Results: There was a significant correlation between age and median motor (p=0) and sensory (p=0) conduction velocities. There was a significant decreasing trend observed in Group III. Conclusions: Age has definite correlation with the NCS in median motor and sensory nerves. It is essential to have reference values with relation to age.

Effect of Iron and Zinc Deficiency on Short Term Memory in Children.

Objective: To evaluate the effect of iron and zinc deficiency on short term memory of children in the age group of 6-11 years and to assess the response to supplementation therapy. Design: Interventional study. Setting: 100 children in the age group of 6-11 years (subdivided into 6-8 yr and 9-11 yr groups) from an urban corporation school. Methods: After collection of demographic data, the study children underwent hematological assessment which included serum iron, serum zinc, and hemoglobin estimation. Based on the results, they were divided into Iron deficient, Zinc deficient, and Combined deficiency groups. Verbal and nonverbal memory assessment was done in all the children. Intervention: Iron (2mg/kg bodyweight in two divided doses) and zinc (5mg once-a-day) supplementation for a period of 3 months for children in the deficient group. Results: All children with iron and zinc deficiency in both the age groups had memory deficits. Combined deficiency in 9-11 years group showed severe degree of affectation in verbal (P<0.01) and non-verbal memory (P<0.01), and improved after supplementation (P = 0.05 and P<0.01, respectively). In 6-8 years group, only non-verbal form of memory (P =0.02) was affected, which improved after supplementation. Conclusion: Iron and zinc deficiency is associated with memory deficits in children. There is a marked improvement in memory after supplementation. Post supplementation IQ scores do not show significant improvement in deficient groups in 6-8 year olds.