Table 1.
Characteristics of study subjects included in immunohistochemical analysis
| Parameters | IPF (n = 50) | Control (n = 10) |
|---|---|---|
| Tissue sample histology, n (%) | ||
| Normal | – | 10 (100) |
| UIP | 47 (94) | – |
| UIP and DAD | 3 (6) | – |
| Two separate lung tissue samples—Surgical lung biopsy and autopsy lung tissue specimen, n (%) | ||
| UIP in biopsy and UIP with DAD in autopsy | 6 (12) | – |
| UIP with DAD in both biopsy and autopsy specimens | 2 (4) | – |
| Age years, mean (SD) | 62.3 (7.9) | 70.5 (6.4) |
| Gender, n (%) | ||
| Male | 37 (74) | 1 (10) |
| Female | 13 (26) | 9 (90) |
| Smoking status, n (%)a | ||
| Never-smoker | 17 (38) | 9 (90) |
| Ex-smoker | 20 (44) | 1 (10) |
| Current smoker | 8 (18) | 0 (0) |
| Pack-years of ever-smokers, median (IQR)b | 25.0 (19.5–37.0) | 7 |
| FVC%, mean (SD)c | 73.8 (15.5) | 100.8 (17.5) |
| FEV1%, mean (SD)c | 78.4 (16.7) | 99.3 (19.3) |
| DLCO%, median (IQR)d | 53.0 (45.0–62.1) | 87.8 (76.4–111.0) |
| Follow up time, months, median (IQR)e | 41.3 (15.1–73.8) | – |
| Episode of AE during follow-up, n (%) | 22 (44) | – |
| Diseased or transplanted, n (%) | 39 (78) | – |
| Transplanted, n (%) | 4 (8.0) | – |
The values were from the time of surgical lung biopsy (IPF). For follow-up time, death or lung transplantation was used as an endpoint event. Follow-up time for patients having no endpoints was defined as the time between biopsy date and May 11, 2021. Non-smoking patients operated for lung cancer were used as controls
AE acute exacerbation, DAD diffuse alveolar damage, DLCO% percent predicted diffuse capacity for carbon monoxide, FEV1% percent predicted forced expiratory volume at one second, FVC% percent predicted forced vital capacity, IQR interquartile range, n number, SD standard deviation, UIP usual interstitial pneumonia
aIPF n = 45
bIPF n = 25
cIPF n = 42, control n = 9
dIPF n = 41, control n = 8
eIPF n = 49