Psychomotor vigilance task performance during total sleep deprivation in young and postmenopausal women.

The objective of this study was to investigate the effects of age on women's performance in the psychomotor vigilance task (PVT) during total sleep deprivation (SD). A total of 46 healthy women volunteered. They belonged to two age groups: young (n=34; age range 19-30 years; 12 without, and 22 with oral contraceptives (OC); early phase of the menstrual cycle) and older (n=12; age range 60-68; postmenopausal; without hormone therapy). During a 40-h total SD, the subjects performed the PVT and the Stanford Sleepiness Scale (SSS) at 2-h intervals. At baseline, the reaction speed of the young women was faster as compared to the older women (Mann-Whitney U-test p<0.01). During SD, all the PVT measures as well as the SSS scores changed similarly in the two age groups, when the baseline performance difference in favour of the young women was taken into account (area under curve analyses, Mann-Whitney U-tests n.s.). No age difference in the time course of the SD-related deterioration in PVT performance or subjective sleepiness was observed. OC use had no effects on any of the measures during SD. After recovery sleep, young women had higher subjective sleepiness scores than older women, the sleepiness scores being highest in young women not taking OCs. In conclusion, in women, aging has no effects on the amount or the time course of the decline in PVT performance caused by total SD. OC use does not significantly affect young women's PVT performance during SD in the early phase of the menstrual cycle.