Study Objectives: This study examined changes in sleep parameters between the laboratory and the home setting before and after laboratory monitoring in depressed insomniacs undergoing treatment. Methods: This study was a post hoc analysis of a double-blind, randomized, placebo-controlled clinical trial performed with 60 depressed, insomniac outpatients. Patients underwent actigraphic monitoring along with sleep diaries over a continuous 2-week period. After one week of baseline monitoring, subjects spent one night in the laboratory with concurrent actigraphic and PSG monitoring with sleep diaries. Actigraphic monitoring and sleep diaries were continued for another week at home, along with initiation of open-label fl uoxetine (FLX). Results: Actigraphically recorded laboratory sleep during the night in the laboratory was found to be improved relative to actigraphically recorded sleep at home, with less wake time and greater sleep time and sleep effi ciency occurring in the laboratory. In contrast, sleep diaries indicated a slight worsening of sleep in the laboratory compared to home, with signifi cantly more awakenings in the laboratory compared to the week at home before and after the laboratory night.
Conclusions
S C I E N T I F I C I N V E S T I G A T I O N SM any individuals experience worse sleep during their fi rst night in a sleep laboratory than on successive nights. This "fi rst night effect" (FNE) is typically characterized by increased sleep onset latency, increased REM latency, a lower percentage of REM stage sleep, and lower sleep effi ciency as measured by polysomnography (PSG). While many studies have observed the FNE phenomenon in normal subjects and in those with depression or insomnia, 1-3 others have observed a reduced or absent FNE. [4][5][6] It has been suggested that factors such as the location of monitoring or pleasantness of the laboratory environment may attenuate this effect, or that individual variability may cancel out differences for entire samples.
5,7-10Many studies observing a FNE have also noted a "paradoxical" or "reverse" fi rst night effect (RFNE) in some of their subjects.11-14 The RFNE is characterized by the observation of decreased sleep onset latency, decreased REM latency, a higher percentage of REM, and greater sleep effi ciency in the fi rst night at the laboratory relative to successive nights, as measured by PSG.13 For insomniacs who demonstrate this phenomenon, several explanations have been proposed. Hauri et al. suggested that maladaptive reinforcements are formed between the insomniac's sleeping problems and their normal sleep environment. 13,15 This conditioned arousal reaction to their normal sleep environment does not generalize to the novel sleep environment of the laboratory, where they fall asleep more easily. Alternatively, de la Pena proposed that some insomniacs require a higher level of waking sensory stimulation to induce sleep, and the greater sensory stimulation of the novel laboratory environment improves their sleep.
16Studies investigating sleep ...