Correlation (r values) between lung function and HRCT parameters in asthmatic patients (n = 45)
| MLD (HU) | RA950 (%) | ||||
| r value | p value | r value | p value | ||
| Age (years) | –0.456 | 0.0018 | 0.405 | 0.0062 | |
| FVC (% pred) | 0.116 | NS | –0.278 | NS | |
| FEV1 (% pred) | 0.666 | <0.0001 | –0.746 | <0.0001 | |
| FEV1/FVC (%) | 0.556 | <0.0001 | –0.574 | <0.0001 | |
| FEF25–75 (% pred) | 0.441 | 0.0032 | –0.495 | 0.0006 | |
| TLC (% pred) | –0.379 | 0.0126 | 0.332 | 0.0358 | |
| FRC (% pred) | –0.312 | 0.0448 | 0.345 | 0.0246 | |
| RV (% pred) | –0.381 | 0.0120 | 0.511 | 0.0004 | |
| RV/TLC (%) | –0.239 | NS | 0.341 | 0.0251 | |
| Tlco (% pred) | –0.115 | NS | 0.096 | NS | |
| Tlco/VA (% pred) | –0.056 | NS | –0.008 | NS | |
HRCT = high resolution computed tomography; MLD = mean lung density; HU = Hounsfield units; RA950 = relative area of the lung with attenuation values lower than –950 HU; FEF25–75 = mean forced expiratory flow during the middle half of the FVC; NS = not significant. Other abbreviations as in footnote to table 1.