Table 1

Mean (SD) respiratory, sleep stage, and arousal results

DiagnosticManualAutoSetFixed
Apnoea + hypopnoea index (events/h)60.3  (5.7)10.1  (3.0)  2.8 (0.9)m**   2.5 (0.7)d***
Apnoea duration (s)34.7 (2.1)22.4 (1.5)16.1  (1.9)m* 16.1  (2.2)d***
Mean nadir saturation (%)70.9 (2.2)84.8 (1.4)90.4 (0.8)m** 90.0 (0.9)d***
Total sleep time (min)357 (4.6)366 (4.3)344 (5.8)m*** 358 (4.3)a**
Stage 1 sleep (%)28.6 (4.0)14.7 (1.9)13.8 (1.6)12.9 (1.5)d**
Stage 2 sleep (%)46.9 (2.9)25.8 (2.4)26.0 (2.3)29.0 (2.4)d***
Slow wave sleep (%)8.1 (2.2)30.5 (4.2)29.8 (3.1)32.5 (2.9)d***
REM sleep (%)10.3 (1.6)22.9 (1.5)21.0 (1.3)20.4 (1.8)d***
Respiratory arousal index (events/h)49.6 (4.9)7.9 (2.4)1.5 (0.6)m** 1.3 (0.4)d***
Non-respiratory arousal index (events/h)3.1 (0.6)6.3 (0.7)7.4 (0.8)8.2 (1.0)d***
  • Diagnostic = diagnostic study without CPAP; manual = manual titration night; AutoSet = AutoSet automatic titration night; fixed = conventional fixed pressure treatment at pressure recommended from AutoSet night

  • d*, d**, d***, significantly different from diagnostic (p<0.05, p<0.01, p<0.001, respectively); a*, a**, a***, significantly different from AutoSet (p<0.05, p<0.01, p<0.001, respectively); m*, m**, m***, significantly different from manual titration (p<0.05, p<0.01, p<0.001, respectively).