Table 1 Baseline characteristics of controls and cases with lung squamous cell carcinoma
Control (N = 3172) | Case (N = 793) | P-value | |
|---|---|---|---|
Sex (%) | 1.000 | ||
 Men | 2772 (87.4) | 693 (87.4) | |
 Women | 400 (12.6) | 100 (12.6) | |
Low income (%) | 0.028 | ||
 No | 3133 (98.8) | 775 (97.7) | |
 Yes | 39 (1.2) | 18 (2.3) | |
Urbanization (%) | 0.012 | ||
 Urban | 1593 (50.2) | 356 (44.9) | |
 Suburban | 1082 (34.1) | 286 (36.1) | |
 Rural | 497 (15.7) | 151 (19.0) | |
Age diagnosed with asthma or COPD (year) (mean ± sd) | 71.6 ± 9.4 | 71.6 ± 9.4 | 1.000 |
Months between initiation and index date (mean ± sd)a | 46.3 ± 16.3 | 46.3 ± 16.3 | 1.000 |
No. of health care utilities between initiation and index date | |||
 No. of outpatient visits for asthma (%) | |||
  0–10 | 2925 (92.2) | 698 (88.0) | <0.001 |
  >10 | 247 (7.8) | 95 (12.0) | |
 No. of hospitalization for asthma (%) | |||
  0–2 | 3128 (98.6) | 777 (98.0) | 0.193 |
  >2 | 44 (1.4) | 16 (2.0) | |
 No. of outpatient visits for COPD (%) | |||
  0–10 | 2800 (88.3) | 622 (78.4) | <0.0001 |
  >10 | 372 (11.7) | 171 (21.6) | |
 No. of hospitalization for COPD (%) | |||
  0–2 | 2995 (94.4) | 683 (86.1) | <0.0001 |
  >2 | 177 (5.6) | 110(13.9) | |
Comorbidities (%) | |||
 Pneumonia | 1179 (37.2) | 483 (60.9) | <0.0001 |
 Pulmonary tuberculosis | 214 (6.7) | 132(16.7) | <0.0001 |
 Chronic renal disease | 302 (9.5) | 90 (11.4) | 0.123 |
 Diabetes mellitus | 1035 (32.6) | 271 (34.2) | 0.408 |
 Hyperlipidemia | 999 (31.5) | 213 (26.9) | 0.011 |
 Smoking-related cancers | 63 (2.0) | 40 (5.0) | <0.0001 |
Medication within 2-year prior to index dateb | |||
 ICS, cDDDs per quarter | <0.0001 | ||
  No use | 2866 (90.4) | 607 (76.5) | |
  Lower dose (≦18.8) | 156 (4.9) | 95 (12.0) | |
  Higher dose (>18.8) | 150 (4.7) | 91 (11.5) | |
 OCS (Hydrocortisone equivalent/quarter) | <0.0001 | ||
  No use | 1955 (61.6) | 338 (42.6) | |
  Lower dose (≦90.0 mg) | 644 (20.3) | 195 (24.6) | |
  Higher dose (>90.0 mg) | 573 (18.1) | 260 (32.8) | |
 Aspirin (mg per quarter) | 0.1888 | ||
  No use | 1998 (63.0) | 489 (61.7) | |
  Lower dose (≦3012.5) | 574 (18.1) | 165 (20.8) | |
  Higher dose (>3012.5) | 600 (18.9) | 139 (17.5) |