Abstract

Background: The modern lifestyle is changing the circadian rhythm of the body especially in rotating shift workers. The impact of this might impair cognitive performance of the rotating shift workers who are frequently exposed to unstable circadian rhythm.

Aims and Objective: To evaluate cognitive functions using neurophysiological and neuropsychological methods in rotating night shift and day workers and to compare cognition between the two groups.

Materials and Methods: Forty healthy male security guards (25–35 years) who did rotating night shifts at least for 6 months and 40 day workers ( 25–35 years) who did not do night shift in last 2 years were involved in the study. A battery of neuropsychological tests, latency, and amplitude of P300 were recorded.

Result: Kolmogorov–Smirnov test for normalcy showed the latencies and amplitude of P300 to be normally distributed. Student’s unpaired t-test showed significant difference (p < 0.05) in the various neuropsychological tests and in the latency of P300 between night- and day-shift workers. There was no significant difference in the amplitude of P300.

Conclusion: Night-shift workers who are prone to circadian rhythm alteration will have impaired cognitive performance.

Key words: Circadian rhythm; Shift workers; Sleep deprivation; P300