Sleep and psychomotor vigilance in female shiftworkers

The purpose of this study was to evaluate the relationships between sleep and psychomotor vigilance in female nurses and the changes in these variables over time. Participants comprised 16 staff registered nurses (10 day, 6 night; aged 30-65 years [M = 47.6; SD = 8.1]) who wore wrist actigraphs continuously and completed a 10-min psychomotor vigilance test (PVT-192, Ambulatory Monitoring, Inc., Ardsley, New York) and the Stanford Sleepiness Scale (SSS) in their homes before and after work for three consecutive 24-hr periods. Repeated measures ANOVA revealed that night nurses slept significantly less than day nurses, F(1, 15) = 26.06, p ≤ .001; M = 227.88 ± 37.03 min versus M = 365.75 ± 59.01 min, respectively, daily for three consecutive days. Night nurses napped more frequently and had more changes in the length of their main sleep periods than day nurses. Day nurses reported more wake episodes during main sleep periods. Night nurses were sleepier after work than day nurses; both groups had increased sleepiness after work for the first 2 days and similar psychomotor vigilance test results. These findings suggest that sleep deprivation, irregular sleep patterns, and sleepiness are significant issues for shiftworking nurses. Future study of the characteristics of sleep and sleepiness in a larger sample would be useful to evaluate the focus for interventions to improve sleep and alertness in shiftworking nurses.