Table 2.

Comparison of Sleep Behavior Before and After Covering the Head With the Duvet During Prone and Supine Sleep

Sleep Parameter2½ Months
Prone n = 30Supine n = 30
No CoverCoverDBMSEPNo CoverCoverDBMSEP
Body movements, non-REM (n)0.51.71.20.6.05 0.41.71.30.4.003
Short arousals, REM (n)2.66.74.12.4.1  3.97.33.41.4.02
Sighs, non-REM (n)1.02.01.00.6.07 0.92.81.90.7.01
Sighs with apnea, non-REM (n)1.41.30.10.2.8  2.11.11.00.2<.001
Sighs with apnea, REM (n)1.91.80.10.6.8  3.41.51.90.6.006
Post sigh apnea duration, non-REM (sec)8.04.83.20.9.01 10.5 4.85.71.0<.001
Post sigh apnea duration, REM (sec)5.72.63.10.9.0017.63.83.81.0.01
Apneas 3 to 10 sec, REM (n)12.0 6.35.72.1.01 15.1 7.87.32.5.007
Episodes of periodic breathing, non-REM (n)0.20.10.10.1.6  0.30.10.20.1.007
Episodes of periodic breathing, REM (n)0.40.20.20.2.3  0.70.30.40.1.004
5 Months
Prone n = 23Supine n = 25
No CoverCoverDBMSEPNo CoverCoverDBMSEP
Body movements, non-REM (n)1.52.51.00.6.1  0.82.31.50.6.01
Sighs, non-REM (n)1.22.61.40.7.05 1.52.40.90.6.1
Sighs with apnea, REM (n)2.11.21.30.8.3  3.31.32.00.9.03
Post sigh apnea duration, non-REM (sec)8.82.76.11.0<.001 7.43.93.51.0.003
Post sigh apnea duration, REM (sec)5.71.34.43.4<.001 7.02.44.61.0<.001
Apneas 3 to 10 sec, REM (n)15.9 6.39.63.4.0111.9 2.79.21.7<.001
  • Abbreviations: n, mean number of events per 20 min; DBM, differences between means; SE, standard error of differences between means; P, level of significance for the uncovered vs the covered period.