Table 2. Univariate analysis.
| Patient characteristics | Unadjusted HR (95% CI) | P value |
|---|---|---|
| Age (10 years increase) | 1.02 (0.96, 1.09) | 0.47 |
| Gender | ||
| Female | Reference | |
| Male | 1.19 (1.05, 1.35) | 0.01 |
| Race | ||
| Non-Caucasian | Reference | |
| Caucasian | 1.27 (0.98, 1.65) | 0.07 |
| Stage | ||
| I | Reference | |
| II | 1.94 (1.55, 2.44) | <.0001 |
| III | 3.15 (2.67, 3.71) | <.0001 |
| IV | 5.04 (4.25, 5.96) | <.0001 |
| Smoking status | ||
| Never | Reference | |
| Former | 0.98 (0.82, 1.18) | 0.85 |
| Current | 0.90 (0.74, 1.10) | 0.32 |
| Pack years | ||
| Never smokers | Reference | |
| ≤40 | 0.91 (0.75, 1.10) | 0.33 |
| >40 and <60 | 1.01 (0.82, 1.24) | 0.93 |
| ≥60 | 1.03 (0.84, 1.26) | 0.77 |
| Histologic cell type | ||
| Other cell type | Reference | |
| Adenocarcinoma | 0.67 (0.56, 0.81) | <0.0001 |
| Squamous | 0.77 (0.63, 0.94) | 0.01 |
| α1ATD carrier status¶ | ||
| Non-carriers | Reference | |
| Carriers | 0.93 (0.77, 1.12) | 0.43 |
| Serum level of α1AT (50 unit increase) | ||
| In all patients† | 1.13 (1.09, 1.18) | <.0001 |
| In patients whose blood were drawn before initial treatment‡ |
1.39 (1.19, 1.63) | <.0001 |
Abbreviations: α1ATD, alpha 1-antitrypsin deficiency; α1AT, alpha 1-antitrypsin; HR, hazard ratio; CI: confidence interval.
Other cell type includes large cell, not specified non-small-cell lung cancer, adenosquamous carcinoma, sarcomatoid, and other mixed cell types.
¶
N=1321, number of events= 995.
†
Cox Proportional Hazard model with Landmark Approach. Survival time was calculated from the date of the blood draw to death. N= 1303, number of events= 982.
‡
N= 128, number of events= 110.