Table 1.
Comparison of Clinical Characteristics of ILD patients
| Dallas Cohorts: | P-value (Dallas non-IPF vs. IPF) | Chicago IPF cohort: | San Francisco IPF cohort: | P-value (Three IPF cohorts3) | ||
|---|---|---|---|---|---|---|
|
|
|
|||||
| All Non-IPF ILD (n=221) | IPF cohort (n=149) | IPF cohort (n=139) | IPF cohort (n=54) | |||
| Age at enrollment, mean (SD), years | 56 (13) | 65 (10) | <0·0001 | 68 (9) | 69 (9) | 0·0047 |
| Male, n (%) | 75 (34) | 104 (70) | <0·0001 | 100 (72) | 43 (80) | 0·39 |
| Ethnicity, n (%) | ||||||
| European American | 147 (67) | 126 (85) | 0·00010 | 122 (88) | 40 (75) | 0·11 |
| African American | 38 (17) | 10 (7) | 0·0041 | 10 (7) | 2 (4) | 0·80 |
| Hispanic | 25 (11) | 11 (7) | 0·28 | 5 (4) | 3 (6) | 0·39 |
| Other | 11 (5) | 2 (1) | 0·084 | 2 (1) | 8 (15) | 0·00011 |
| Ever smokers, n (%) | 83 (38) | 94 (63) | 0·00010 | 88 (70) | 39 (72) | 0·35 |
| Baseline Spirometry, mean (SD) | ||||||
| FVC, % predicted | 67 (23) | 62 (21) (n=148) | 0·023 (0·00026) | 64 (18) | 69 (15) | 0·026 (0·12) |
| FEV1, % predicted | 67 (23) | 66 (20) (n=147) | 0·74 (0·067) | 77 (20) (n=137) | NA | <0·0001 (<0·0001) |
| Ratio of FEV1/FVC | 81 (12) (n=211) | 82 (9) (n=148) | 0·49 (0·20) | 84 (8) (n=122) | NA | 0·066 (0·046) |
| DLCO, % predicted | 41 (18) (n=187) | 35 (16) (n=136) | 0·0035 (0·0063) | 48 (18) (n=123) | 46 (16) (n=49) | <0·0001 (<0·0001) |
| Unable to perform DLCO, n (%) | 15 (6·8) | 8 (5·6) | 0·83 | 1 (0·8) | 1 (2·0) | 0·057 |
| Follow up time, median (IQR), months | 27 (13–35) | 15 (9–27) | 0·00013 | 26 (15–49) | 56 (17–72) | <0·0001 |
| Time to Death or Transplant, median (95% CI), months1 | 69 (69-)1 | 21.5 (16–28) | 0·00010 | 67 (46- )1 | 64 (32- )1 | <0·0001 |
| Number of patients undergoing transplant (%) | 13 (6) | 38 (26) | <0·0001 | 11 (8) | 7 (13) | 0·00023 |
| Telomere Length, mean (SD) | 1·46 (0·24) | 1·33 (0·25) | <0·0001 (adjusted 0·47)2 | 1·34 (0·26) | 1·67 (0·37) | <0·0001 |
Abbreviations: SD, standard deviation; FVC, forced vital capacity; FEV1, forced expiratory volume in one second; DLCO, diffusion capacity for carbon monoxide; IQR, interquartile range; 95% CI, 95 percent confidence interval; NA, not available.
The median survival time was estimated using Kaplan-Meier analysis. More than 50% of non-IPF ILD subjects were still alive at the end of the observation period, therefore the median cannot be estimated. The upper 95% confidence limits of median survival time for the San Francisco cohort and Chicago cohorts could not be determined because of the large proportion of transplant-free surviving subjects at the end of the observation period.
The P-values for comparison of Dallas IPF vs. non-IPF patients adjusted for age, male sex, and ethnicity.
The P-values for comparison of Dallas IPF, Chicago IPF and San Francisco IPF cohorts.