Table 2– Respiratory data according to sleep apnoea severity
AHI <5 events·h−1AHI 5–14 events·h−1AHI ≥15 events·h−1p-value
Subjects n13614076
Recording time min463 (413–510)463 (421–512)454 (410–501)0.874
Average O2 saturation %95 (93–95)94 (93–95)94 (93–95)0.003
Desaturation index %5 (2–9)12 (7–17)20 (15–34)<0.001
Minimal O2 saturation %82 (76–87)81 (74–85)79 (73–83)0.037
Cardiac frequency beats·min−160±1461±960±110.889
Epworth Sleepiness Scale score5 (3–8)5 (4–8)7 (4–9)0.184
  • Data are presented as median (interquartile range) or mean±sd, unless otherwise stated. The desaturation index was based on oxygen desaturations ≥3%. AHI: apnoea/hypopnoea index.