TABLE 4

Placebo and zopiclone polysomnography data for the 8-h overnight sleep studies during the baseline and night 30 conditions

Placebo#ZopicloneDelta changep-value
BaselineNight 30BaselineNight 30
Sleep onset latency min10 (6–13)6 (2–15)9 (5–26)16 (10–32)6 (−11–17)0.47
Sleep efficiency % sleep84±785±1079±1386±65 (−2–13)0.16
TST min415±34424±45386±61427±2732 (−2–67)0.07
Non-REM sleep N1 % TST7±45±310±37±4−1 (−3–1)0.35
Non-REM sleep N2 % TST49±849±746±1049±74 (−3–10)0.24
Non-REM sleep N3 % TST25±626±724±724±4−1 (−4–4)0.80
REM sleep % TST19±520±520±519±5−2 (−6–2)0.33
Wake after sleep onset min71±3365±5187±5653±32−28 (−61–6)0.10
Arousal index arousals·h−127±1024±1128±1124±8−1 (−8–6)0.75
Supine % TST48±2852±3149±2846±28−7 (−25–11)0.43
Supine AHI events·h−138±2832±2146±2437±23−2 (−14–18)0.82
Low arousal threshold AHI events·h−1+23±1220±1121±1116±10−1 (−10–8)0.82
Moderate arousal threshold AHI events·h−1§19±718±1026±1419±5−6 (−16–3)0.18
Respiratory event duration s25±327±527±527±5−2 (−6–1)0.20
Mean SaO2 during sleep %95±295±194±294±20 (−1–1)0.93
Nadir SaO2 during sleep %86±586±686±685±5−1 (−4–3)0.64

Data are presented as mean±sd or median (interquartile range), unless otherwise stated; the delta change column indicates the difference from baseline to night 30 between conditions (mean (95% CI) for normally distributed data and Hodge–Lehmann estimated median (95% CI) for nonnormally distributed data). REM: rapid eye movement; TST: total sleep time; AHI: apnoea–hypopnoea index; SaO2: estimated arterial blood oxygen saturation (measured via pulse oximetry). #: n=16; : n=14; +: for low arousal threshold (> −15 cmH2O) AHI, n=9 in the placebo group and n=7 in the zopiclone group; §: for moderate arousal threshold (< −15 and > −25 cmH2O) AHI, n=7 in the placebo and zopiclone groups. p-values refer to the difference from baseline to night 30 compared between placebo and zopiclone conditions.