Table 2.
Comparison of lung parameters in all lung biopsies by smoking status separate for lung fibrosis patients and controls.
| Never smokers | Previous smokers | Current smokers | p-value | |
|---|---|---|---|---|
| Cases | ||||
| MDA, μmol/g lung tissue | 98 (89–125) | 103 (94–131) | 100 (97–102) | 0.52 |
| COX/SDH-ratio | 0.12 (0.09–0.14) | 0.07 (0.03–0.11) | 0.11 (0.10–0.13) | 0.17 |
| mtDNA, copies/pulmonary cell | 385 (325–484) | 414 (365–487) | 426 (365–487) | 0.92 |
| COX2/COX4-ratio | 0.81 (0.57–1.01) | 0.64 (0.51–0.83) | 0.73 (0.47–0.99) | 0.28 |
| common deletion, % of mtDNA molecules | 8.0 (0–31) | 24.3 (0–32) | 27.1 (22–32) | 0.21 |
| Controls | ||||
| MDA, μmol/g lung tissue | 115 | 91 (66–102) | 89 (87–91) | 0.29 |
| COX/SDH-ratio | 0.14 | 0.12 (0.11–0.19) | 0.15 (0.12–0.18) | 0.82 |
| mtDNA, copies/pulmonary cell | 262 | 342 (304–504) | 327 (315–339) | 0.47 |
| COX2/COX4-ratio | 2.10 | 2.20 (1.98–2.44) | 1.98 (1.79–2.18) | 0.45 |
| common deletion, % of mtDNA molecules | 12.7 | 0 (0–14) | 0 (0–0) | 0.41 |
Presented are medians and interquartile ranges.
COX2/COX4, cytochrome c-oxidase subunit 2 protein normalized for cytochrome c-oxidase subunit 4 protein; COX/SDH-ratio, cytochrome c-oxidase/succinate dehydrogenase activity ratio; MDA, malondialdehyde; mtDNA, mitochondrial DNA.