Table 2.
Comparison Between Patients in Whom CPAP Was Successfully Titrated and Patients Who Were Shifted to BPAP
| Variable Total (n=54) | Mean ± SD/n (%) | P-Value | |
|---|---|---|---|
| CPAP (n=36) | BPAP (n=18) | ||
| Age (Year) | 53.4 ± 13.3 | 57.7 ± 16.9 | 0.307 |
| Body mass index (kg/m2) | 45.7 ± 11.6 | 46.1 ± 10.2 | 0.1 |
| Epworth sleepiness scale | 8.6 ± 5.3 | 8.9 ± 5.3 | 0.821 |
| PaCO2 (mmHg) | 49 ± 4.7 | 63.7 ± 11.5 | < 0.001 |
| PaO2 (mmHg) | 69.4 ± 17.7 | 62.5 ± 16.6 | 0.178 |
| HCO3 (mmol/L) | 29.1 ± 2.4 | 35.1 ± 13.3 | 0.006 |
| FEV1/FVC (%) | 85.4 ± 6.1 | 85 ± 7.5 | 0.875 |
| FVC (% predicted) | 76.1 ± 19.3 | 49.4 ± 14.4 | 0.001 |
| FEV1 (% predicted) | 79.4 ± 19.5 | 50.6 ± 12.5 | < 0.001 |
| Sex (Female) | 27 (75) | 14 (77.8) | 1.000 |
| Premenopausal | 9 (25) | 2 (11.1) | 0.429 |
| Comorbidities | |||
| Hypertension | 22 (61) | 15 (83.3) | 0.21 |
| Ischemic heart disease | 4 (11) | 2 (11.1) | 1.00 |
| Diabetes mellitus | 16 (44.4) | 13 (72.2) | 0.08 |
| Renal failure | 0 (0) | 2 (11.1) | 0.11 |
| Compensated heart failure | 2 (5.6) | 1 (5.6) | 1.00 |
| Bronchial asthma | 15 (41.7) | 4 (22.2) | 0.16 |
| Allergic rhinitis | 5 (13.9) | 0 (0) | 0.26 |
| Hypothyroidism | 6 (16.7) | 1 (5.6) | 0.40 |
| Hypercholesterolemia | 15 (41.7) | 4 (22.2) | 0.25 |
| Polysomnographic findings at baseline | |||
| Sleep efficiency (%) | 72.1 ± 16.5 | 67.6 ± 20.9 | 0.39 |
| Stage N1 (%) | 7.7 ± 5.6 | 11 ± 14.7 | 0.83 |
| Stage N2 (%) | 71.5 ± 17.1 | 63.4 ± 19.6 | 0.12 |
| Stage N3 (%) | 8.7 ± 15.1 | 9.8 ± 13.2 | 0.67 |
| Stage REM (%) | 11.9 ± 9.3 | 14.6 ± 16.2 | 0.52 |
| Apnea hypopnea index (events/hr) | 17.4 ± 7.8 | 15.3 ± 7.8 | 0.35 |
| Central apnea index (events/hr) | 0 ± 0.1 | 0 ± 0.1 | 0.946 |
| Obstructive apnea index (events/hr) | 0.6 ± 1.2 | 0.6 ± 1.7 | 0.577 |
| Mixed apnea index (events/hr) | 0.7 ± 4.4 | 0.1 ± 0.1 | 0.079 |
| Hypopnea index (events/hr) | 16.8 ± 7.6 | 14 ± 7.6 | 0.205 |
| Desaturation index (desaturations/hr) | 24.1 ± 22.1 | 12.2 ± 8.5 | 0.026 |
| Time with SpO2 <90% (mins) | 20.4 ± 34.2 | 65.4 ± 37.2 | < 0.001 |
| Lowest recorded SpO2 (%) | 81.1 ± 11.7 | 69.8 ± 11.8 | < 0.001 |
| Mean nocturnal SpO2 (%) | 91.8 ± 10.9 | 84.4 ± 7.7 | < 0.001 |
| Arousal index (arousals/hr) | 22.1 ± 9.9 | 21.5 ± 11.5 | 0.76 |
| Polysomnographic findings during successful titration | |||
| Sleep efficiency (%) | 76 ± 15.7 | 61.4 ± 22.3 | 0.01 |
| Stage N1 (%) | 7 ± 5.8 | 11.9 ± 14 | 0.49 |
| Stage N2 (%) | 65.5 ± 15.4 | 64.5 ± 18.2 | 0.649 |
| Stage N3 (%) | 6 ± 9.7 | 8.9 ± 12.1 | 0.59 |
| Stage REM (%) | 21.2 ± 11.4 | 14.1 ± 11 | 0.04 |
| Apnea hypopnea index (events/hr) | 5.9 ± 6.2 | 8.3 ± 7.3 | 0.216 |
| Central apnoea index (events/hr) | 0.4 ± 1.3 | 0.1 ± 0.2 | 0.732 |
| Obstructive apnoea index (events/hr) | 0.3 ± 1 | 0.3 ± 0.8 | 0.438 |
| Mixed apnoea index (events/hr) | 0.1 ± 0.2 | 0 ± 0.1 | 1.000 |
| Hypopnea index (events/hr) | 4.6 ± 4.5 | 7.9 ± 7 | 0.094 |
| Desaturation index (desaturations/hr) | 4.7 ± 4.8 | 4.9 ± 5 | 0.917 |
| Time with SpO2 <90% (mins) | 0.9 ± 2.1 | 15.7 ± 23.7 | 0.002 |
| Lowest recorded SpO2 (%) | 90.6 ± 3 | 81 ± 18.6 | 0.017 |
| Mean nocturnal SpO2 (%) | 95.7 ± 1.7 | 94.1 ± 2.7 | 0.015 |
| Arousal index (arousals/hr) | 12.8 ± 9.2 | 15.6 ± 14.3 | 0.868 |
| Required supplemental oxygen | – | 2 (11.1) | |
| PAP device pressure | |||
| PAP recommended pressure | 11 ± 3.4 | 14.8 ± 3/10.1 ± 2.5 | - |
Abbreviations: HCO3, bicarbonate; FEV1, forced expiratory volume in 1 sec; FVC, forced vital capacity; SPO2, percent saturation of oxygen in the blood; PAP, positive airway pressure.