TABLE 2.
CLINICAL FEATURES OF PATIENTS WITH OBESITY HYPOVENTILATION SYNDROME
| Variable | Mean (range) |
|---|---|
| Age, yr | 52 (42–61) |
| Men, % | 60 (49–90) |
| Body mass index, kg/m2 | 44 (35–56) |
| Neck circumference, cm | 46.5 (45–47) |
| pH | 7.38 (7.34–7.40) |
| PaCO2, mm Hg | 53 (47–61) |
| PaO2, mm Hg | 56 (46–74) |
| Serum bicarbonate, mEq/L | 32 (31–33) |
| Hemoglobin, g/dl | 15 |
| Apnea–hypopnea index | 66 (20–100) |
| Oxygen nadir during sleep, % | 65 (59–76) |
| Percent time SaO2 less than 90%, % | 50 (46–56) |
| FVC, %pred | 68 (57–102) |
| FEV1, %pred | 64 (53–92) |
| FEV1/FVC | 77 (74–88) |
| Medical Research Council dyspnea class 3 and 4, % | 69 |
| Epworth Sleepiness Scale, score | 14 (12–16) |