Patients' Estimates of Their First Night Effects during in-Laboratory Polysomnography Using a Morning Questionnaire

Abstract

Objective: The purpose of this study is to investigate first night effect (FNE) and reverse first night effect (RFNE) by conducting a questionnaire survey targeting patients that received in-laboratory polysomnography (PSG) on the previous day, and to analyze the differences in FNE and RFNE by sleep disorder group. Background: Due to the new environment, patients can either sleep badly or soundly compared to usual days. In some studies, FNE and RFNE are different depending on the type of sleep disorder.

Design/Methods: Total 199 patients were included. Each of them was hospitalized in a single in-laboratory PSG room for a day to receive the examination, and then their subjective quality of sleep was evaluated through a questionnaire survey on the next day. The questionnaire items consisted of time in bed, sleep latency, wake-up time, subjective total sleep time, and the number of awakenings after sleep onset. Visual Analog Scale was used to represent that, considering the normal sleep state as 0, if they slept more soundly than usual, they were made add numbers, and if they slept more badly than usual, they were made to subtract numbers.

Results: The mean VAS score was −0.20 ± 4.76. 28.6 % of them answered that they slept normally, 30.2 % more soundly, and 41.2 % more badly. Those with REM sleep related behavior disorders (RBD, n=15) and restless legs syndrome (RLS, n=19) answered that they slept more badly than usual (mean VAS score, RBD: −1.53 ± 4.64, RLS: −2.58 ± 3.82), and those with insomnia answered that they slept more soundly than usual (mean VAS score 0.93 ± 4.86, P = 0.014).

Conclusions: Subjective first night effect measured using self-reported questionnaire vary according to the type of sleep disorder. Further study is needed for clinical significance of the subjective first night effect.

Disclosure: Dr. MOON has nothing to disclose. Dr. Byun has nothing to disclose. Dr. Lee has nothing to disclose. Dr. Cho has nothing to disclose.