TABLE 1.
COMPARISON OF BASELINE CHARACTERISTICS OF 1,045 PATIENTS INCLUDED IN CURRENT ANALYSIS WITH LOW VERSUS HIGH UPPER ZONE PERFUSION
| Upper Zone Perfusion <20% |
Upper Zone Perfusion ≥20% |
||
|---|---|---|---|
| Baseline Characteristic | (n = 555) | (n = 490) | P Value |
| Demographic factors | |||
| Age, median (IQR), yr | 68 (64, 71) | 68 (64, 71) | 0.61 |
| Female, % | 37 | 43 | 0.050 |
| Body mass index, median (IQR), kg/m2 | 25 (22, 27) | 25 (22, 28) | 0.47 |
| Smoking history | |||
| Pack-years of smoking, median (IQR) | 60 (42, 84) | 61 (42, 82) | 0.60 |
| Years since quitting, median (IQR) | 8 (4, 14) | 8 (4, 15) | 0.31 |
| Pulmonary function | |||
| FEV1, median (IQR), % predicted | 27 (22, 32) | 28 (23, 32) | 0.31 |
| FVC, median (IQR), % predicted | 68 (59, 78) | 69 (59, 79) | 0.50 |
| RV, median (IQR), % predicted | 212 (185, 245) | 208 (184, 238) | 0.20 |
| TLC, median (IQR), % predicted | 127 (116, 136) | 127 (117, 136) | 0.59 |
| DlCO, median (IQR), % predicted | 28 (22, 34) | 29 (24, 36) | 0.003 |
| Arterial blood gases | |||
| PaO2, median (IQR), mm Hg | 66 (59, 74) | 63 (56, 70) | <0.001 |
| PaCO2, median (IQR), mm Hg | 42 (38, 45) | 42 (39, 46) | 0.09 |
| Quality-of-life scores | |||
| SGRQ total score, median (IQR) | 53 (43, 62) | 53 (43, 61) | 0.69 |
| SOBQ score, median (IQR) | 63 (51, 74) | 61 (48, 37) | 0.99 |
| Maximal exercise capacity, median (IQR), W | 38 (25, 51) | 38 (25, 51) | 0.67 |
| LVEF <45%,* % | 4.0 | 3.5 | 0.74 |
| Percent emphysema in upper zone, median (IQR)† | 29 (18, 40) | 9 (3, 19) | <0.001 |
Definition of abbreviations: DlCO = diffusing capacity of carbon monoxide; IQR = interquartile range; LVEF = left ventricular ejection fraction; RV = residual volume; SGRQ = St. George Respiratory Questionnaire; SOBQ = University of California at San Diego Shortness-of-Breath Questionnaire; TLC = total lung capacity.
*
Measured by transthoracic echocardiography.
†
Measured by computed tomography densitometry and available for 606 patients.