Table 1.
Pre-ILD baseline demographic and clinical characteristics
| Demographics | Total (N = 114,921) |
IPF (N = 5,555) |
Non-IPF ILD (N = 109,366) |
p-value |
|---|---|---|---|---|
| Age (continuous), mean (SD) | 66.9 (14.2) | 72.4 (10.4) | 66.7 (14.3) | < 0.001 |
| Gender, n (%) | < 0.001 | |||
| Female | 60,669 (52.8) | 2,167 (39.0) | 58,502 (53.5) | |
| Male | 54,252 (47.2) | 3,388 (61.0) | 50,864 (46.5) | |
| US Region1, n (%) | ||||
| Northeast | 25,815 (22.5) | 1,326 (23.9) | 24,489 (22.4) | 0.010 |
| Midwest | 46,507 (40.5) | 2,145 (38.6) | 44,362 (40.6) | 0.004 |
| South | 31,701 (27.6) | 1,509 (27.2) | 30,192 (27.6) | 0.472 |
| West | 10,898 (9.5) | 575 (10.4) | 10,323 (9.4) | 0.024 |
| Race, n (%) | ||||
| White | 77,744 (67.7) | 4,073 (73.3) | 73,671 (67.4) | < 0.001 |
| African American | 11,492 (10.0) | 274 (4.9) | 11,218 (10.3) | < 0.001 |
| Asian | 1,824 (1.6) | 113 (2.0) | 1,711 (1.6) | 0.006 |
| Unknown | 23,861 (20.8) | 1,095 (19.7) | 22,766 (20.8) | 0.048 |
| Ethnicity, n (%) | ||||
| Hispanic | 5,455 (4.8) | 227 (4.1) | 5,228 (4.8) | 0.018 |
| Not Hispanic | 78,150 (68.0) | 3,825 (68.9) | 74,325 (68.0) | 0.162 |
| Unknown | 31,316 (27.3) | 1,503 (27.1) | 29,813 (27.3) | 0.740 |
| Insurance type, n (%) | ||||
| Commercial only | 39,533 (34.4) | 1,718 (30.9) | 37,815 (34.6) | < 0.001 |
| Medicare only | 49,475 (43.1) | 2,825 (50.9) | 46,650 (42.7) | < 0.001 |
| Medicaid only | 12,420 (10.8) | 269 (4.8) | 12,151 (11.1) | < 0.001 |
| Multiple known types | 10,194 (8.9) | 552 (9.9) | 9,642 (8.8) | 0.004 |
| Unknown type | 3,299 (2.9) | 191 (3.4) | 3,108 (2.8) | 0.009 |
| Baseline Charlson comorbidity score (continuous), mean (SD) | 2.5 (2.4) | 1.8 (1.9) | 2.5 (2.5) | < 0.001 |
| Baseline Charlson comorbidity score (categorical), n (%) | ||||
| 0 | 26,689 (23.2) | 1,723 (31.0) | 24,966 (22.8) | < 0.001 |
| 1–2 | 40,841 (35.5) | 2,196 (39.5) | 38,645 (35.3) | < 0.001 |
| 3–4 | 25,885 (22.5) | 1,123 (20.2) | 24,762 (22.6) | < 0.001 |
| 5+ | 21,506 (18.7) | 513 (9.2) | 20,993 (19.2) | < 0.001 |
| Underlying ILD type, n (%) | ||||
| Autoimmune ILD | 17,827 (15.5) | 0 (0) | 17,827 (16.3) | |
| Hypersensitivity pneumonitis | 19,570 (17.0) | 0 (0) | 19,570 (17.9) | |
| Sarcoidosis | 3,801 (3.3) | 0 (0) | 3,801 (3.5) | |
| Multiple known types | 4,094 (3.6) | 0 (0) | 4,094 (3.7) | |
| Unclassified | 69,629 (60.6) | 5,555 (100) | 64,074 (58.6) | |
| Medications, n (%) | ||||
| Antibiotics | 62 (0.1) | 42 (0.8) | 20 (0.0) | < 0.001 |
| Corticosteroids | 43,698 (38.0) | 1,799 (32.4) | 41,899 (38.3) | < 0.001 |
| Biologics | 3,078 (2.7) | 88 (1.6) | 2,990 (2.7) | < 0.001 |
| Calcineurin inhibitors | 959 (0.8) | 43 (0.8) | 916 (0.8) | 0.612 |
| Other immunosuppressants | 4,024 (3.5) | 62 (1.1) | 3,962 (3.6) | < 0.001 |
| Respiratory conditions, n (%) | ||||
| Pulmonary hypertension | 9,611 (8.4) | 394 (7.1) | 9,217 (8.4) | < 0.001 |
| Acute respiratory failure | 17,880 (15.6) | 465 (8.4) | 17,415 (15.9) | < 0.001 |
| Asthma | 20,259 (17.6) | 686 (12.4) | 19,573 (17.9) | < 0.001 |
| COPD | 40,500 (35.2) | 1,688 (30.4) | 38,812 (35.5) | < 0.001 |
| Pneumonia | 29,785 (25.9) | 1,110 (20.0) | 28,675 (26.2) | < 0.001 |
| Lung transplantation | 312 (0.3) | 46 (0.8) | 266 (0.2) | < 0.001 |
| URTI | 25,908 (22.5) | 1,052 (18.9) | 24,856 (22.7) | < 0.001 |
| LRTI | 21,788 (19.0) | 876 (15.8) | 20,912 (19.1) | < 0.001 |
| Lung cancer | 4,598 (4.0) | 75 (1.4) | 4,523 (4.1) | < 0.001 |
| Cystic fibrosis | 217 (0.2) | 3 (0.1) | 214 (0.2) | 0.018 |
| Other clinical characteristics, n (%) | ||||
| Oxygen therapy use | 21,343 (18.6) | 776 (14.0) | 20,567 (18.8) | < 0.001 |
| Evidence of smoking | 46,885 (40.8) | 1,747 (31.5) | 45,138 (41.3) | < 0.001 |
| Pulmonary rehabilitation | 773 (0.7) | 42 (0.8) | 731 (0.7) | 0.435 |
Abbreviations: IPF– idiopathic pulmonary fibrosis; ILD– interstitial lung disease; SD– standard deviation; URTI– upper respiratory tract infection; LRTI– lower respiratory tract infection
Notes: 1States included in each region are as follows: Northeast (CT, MA, ME, NH, RI, VT, NJ, NY, PA); Midwest (IL, IN, MI, OH, WI, IA, KS, MN, MO, ND, NE, SD); South (DC, DE, FL, GA, MD, NC, SC, VA, WV, AL, KY, MS, TN, AR, LA, OK, TX); West (AZ, CO, ID, MT, NM, NV, UT, WY, AK, CA, HI, OR, WA)
2The identification period used only partial years in 2016 (October - December) and 2022 (January - July)