Table 3.
Baseline polygraphic characteristics of the study population according to positional category.
| All | NPOSA | POSA | P Value vs NPOSA | e-POSA | P Value vs NPOSA | |
|---|---|---|---|---|---|---|
| Apnea duration, s | 16.6 (6.3) | 17.0 (6.5) | 16.3 (6.0) | < .0001 | 15.4 (6.6) | < .0001 |
| Events duration, s | 19.2 (4.1) | 19.1 (4.3) | 19.3 (4.0) | .1166 | 19.4 (4.2) | .0050 |
| Fhyponea, % | 73.2 (23.9) | 70.2 (26.2) | 75.8 (21.3) | < .0001 | 79.9 (18.8) | < .0001 |
| Desaturation indices | ||||||
| 3% ODI, events/h | 13.9 (17.6) | 20.0 (21.9) | 8.5 (10.1) | < .0001 | 3.9 (5.3) | < .0001 |
| 4% ODI, events/h | 10.4 (15.8) | 15.7 (20.1) | 5.9 (8.4) | < .0001 | 2.4 (4.0) | < .0001 |
| T90, % | 9.2 (16.5) | 13.7 (19.9) | 5.2 (11.5) | < .0001 | 2.8 (9.0) | < .0001 |
| Nadir Sao2, % | 80.7 (8.7) | 78.1 (9.8) | 83.1 (6.7) | < .0001 | 85.4 (5.3) | < .0001 |
| Hypoxic burden | 67.1 (90.5) | 96.2 (117.5) | 41.7 (43.8) | < .0001 | 20.4 (21.4) | < .0001 |
Data are expressed as mean (standard deviation) or percentages. P values are based on t tests. e-POSA = exclusive positional obstructive sleep apnea, Fhypopnea = fraction of events that were hypopneas, NPOSA = nonpositional obstructive sleep apnea, ODI = oxygen desaturation index, POSA = positional obstructive sleep apnea, T90 = percentage of sleep (recording) time with oxygen saturation (Sao2) < 90%.