Effects Of Triazolam And Zaleplon On Polysomnographic Examination And Cognitive Function

ObjectivesTo explore the effects of the short-acting hypnotics of triazolam and zaleplon, on polysomnographic examination and cognitive function.Methods(1) The study was conducted according to a single-blind, 2-way cross-over design. 10 young healthy volunteers participated in this research. Either 0.25mg triazolam or 10mg zaleplon was administrated to the subjects by randomized allocation with a single oral administration at about 23:00h. A polysomnography (PSG) was recorded on 1 baseline and 2 medication nights for each subject from about 23:00 to 07:00 the following day. Then, performance tests were performed and subjective data were collected which began at about 07:15. There was a 7-days interval as washout period between the two medication nights.(2)This was a single-blind, 2-crossover study in which 30 healthy volunteers were randomized to 0.25mg oral dose of triazolam or 10mg oral dose of zaleplon. Performance tests were completed at -1.0predrug and 1.0(zaleplon) or 1.5(triazolam),3.0,6.0 hours postdrug. At same time, advert events were recorded .There was a 7-days interval as washout period between the two medication days.Results(1)According to the PSG, both 0.25mg triazolam and 10mg zaleplon shortened sleep latency significantly compared with baseline. Besides, Triazolam resulted in a significant increase in total sleep time,NREM periods,sleep efficiency and stage2% and a signicant decrease in REM%. No significant differences were observed in any sleep architecture variables between zalaplon and baseline.(2)Compared with triazolam, the total sleep time and NREM periods were significant shorter in zaleplon group, and latency to stage3 was significant shorter in zaleplon group.(P<0.05)(3)With regard to carryover effects, neither of the drugs had any significant effect on performance, attention,woking memory and psychomotor.(P>0.05)(3)Administrated at morning, zaleplon 10mg was devoid of residual effects regardless of the time of testing, except for CPT(continuous performance test) and Combination Reaction Time when tested at 1.0 hour postdrug relative to baseline. Compared with baseline, the number of missing responses , false responses and reaction time was significantly different from baseline. Triazolam significantly impaired CPT and Combination Reaction Time at 1.5hours postdrug, and it significantly impaired CPT at 3.0 hours postdrug. Further more, zaleplon differed from triazolam in the extent of performance impairment at 1/1.5 and 3.0 hours postdrug.Conclusions(1) Administrated at bedtime, triazolam shortened sleep latency, increased sleep efficiency and altered sleep architecture. While zaleplon shortened sleep latency, but did not alter sleep architecture.(2) Administrated at bedtime, neither triazolam nor zaleplon had any significant effects on performance, attention,woking memory and psychomotor at the next morning.(3) Administrated at morning , both triazolam and zaleplon impaired attention. Furthermore, compared with triazolam, zaleplon produced less and shorter period attention impairment.