Table 1.
Characteristics of LSC subjects with and without ever WS exposure for over a year
| Variable | WS exposure for over a year | P | |
|---|---|---|---|
| Ever | Never | ||
| N | 684 | 1688 | |
| Baseline variables | |||
| Age (year, mean ± SD) | 55.3 ± 9.0 | 56.7 ± 9.5 | 0.0013* |
| Male sex (n, %) | 188 (27.5) | 438 (26.0) | 0.44† |
| Ethnicity (n, %) | < 0.0001† | ||
| NHW | 457 (66.8) | 1286 (76.2) | |
| Hispanic | 165 (24.1) | 271 (16.1) | |
| Other ethnicities | 62 (9.1) | 131 (7.8) | |
| Current smoker (n, %) | 425 (62.1) | 957 (56.7) | 0.015† |
| Packyears (median, IQR) | 35.5 (26.8–48.5) | 34.5 (25.5–48.5) | 0.35‡ |
| Time since quit (year, median, IQR) | 6.3 (2.2–15.4) | 9.4 (3.5–18.3) | 0.0026‡ |
| College education (n, %)†† | 450 (66.0) | 1190 (70.7) | 0.024† |
| Annual income ≥ 30 K (n, %)‡‡ | 248 (44.6) | 684 (52.2) | 0.0034† |
| FEV1 (L/s, mean ± SD) | 2.54 ± 0.77 | 2.59 ± 0.76 | 0.21* |
| FVC (L, mean ± SD) | 3.51 ± 0.94 | 3.53 ± 0.95 | 0.73* |
| FEV1/FVC ratio (%, mean ± SD) | 72.3 ± 11.3 | 73.4 ± 10.2 | 0.024* |
| Airway obstruction (n, %) | 215 (31.4) | 442 (26.2) | 0.0097† |
| CMH (n, %) | 222 (32.4) | 398 (23.5) | < 0.0001† |
| Sputum MI (median, IQR)§ | 2 (1–4) | 2 (1–4) | 0.90‡ |
| Charlson comorbidity score ≥ 1 (n, %) | 412 (60.2) | 819 (48.5) | < 0.0001† |
| HRQoL: SF-36 (mean ± SD, % with score 100) | |||
| Physical functioning | 71.0 ± 27.3, 15.5|| | 78.1 ± 24.1, 22.1 | < 0.0001* |
| Role physical | 67.8 ± 40.5, 55.9|| | 79.1 ± 35.0, 69.1 | < 0.0001* |
| Bodily pain | 61.6 ± 26.2, 17.4|| | 68.8 ± 24.8, 24.9 | < 0.0001* |
| Role emotional | 69.7 ± 41.7, 61.7|| | 77.1 ± 38.5, 71.3 | < 0.0001* |
| Social functioning | 75.5 ± 27.2, 41.8|| | 82.2 ± 24.4, 52.7 | < 0.0001* |
| Mental health | 70.1 ± 20.2, 3.2** | 74.9 ± 19.4, 5.3 | < 0.0001* |
| Vitality | 51.1 ± 23.8, 1.3 | 57.5 ± 21.9, 1.9 | < 0.0001* |
| General health perceptions | 61.8 ± 22.6, 3.7 | 68.7 ± 21.1, 4.9 | < 0.0001* |
| HRQoL: SGRQ (mean ± SD, % with score 0) | |||
| Symptom | 39.1 ± 24.9, 5.3|| | 28.1 ± 22.2, 11.9 | < 0.0001* |
| Activity | 38.1 ± 25.9, 8.5|| | 29.2 ± 24.5, 16.1 | < 0.0001* |
| Impact | 16.2 ± 16.2, 18.7|| | 10.3 ± 13.4, 35.6 | < 0.0001* |
| Total | 27.8 ± 19.54, 1.0|| | 19.6 ± 17.0, 4.3 | < 0.0001* |
| Longitudinal data | |||
| # Spirometry (median, IQR) | 3 (1.5–6) | 4 (2–7) | 0.0008‡ |
| Duration in cohort (year, median, IQR) | 3.6 (0.5–8.5) | 4.6 (1.4–9.6) | 0.0013‡ |
| # SGRQ (median, IQR) | 2 (1–5) | 2 (1–6) | 0.12‡ |
| # Death by 2020 (n, %) | 108 (15.8) | 272 (16.1) | 0.85† |
| Age at death (year, mean ± SD) | 69.3 ± 10.3 | 72.8 ± 10.2 | 0.0029* |
| Primary cause of death (n, %) | 0.90† | ||
| Cardio pulmonary diseases | 41 (38.0) | 114 (41.9) | |
| Cancers | 35 (32.4) | 84 (30.9) | |
| Other causes | 32 (29.6) | 74 (27.2) | |
| Lung cancer incidence (n, %) | 22 (3.2) | 50 (3.0) | 0.74† |
| Age at LC diagnosis (year, mean ± SD) | 68.6 ± 8.2 | 69.9 ± 8.2 | 0.56* |
CMH chronic mucous hypersecretion, HRQoL health related quality of life, IRQ inter quartile range, NHW non-Hispanic white, SD standard deviation, SGRQ St. George’s Respiratory questionnaire, MI methylation index, WS woodsmoke
*Student t test. Age at death was missing for one subject with ever WS exposure
†Chi-square test
‡Wilcoxon rank sum test
§Sputum MI is available in 521 subjects with ever WS exposure for over a year and 1280 subjects without
||Chi-square test, P < 0.0001, compared to never WS exposure
**Chi-square test, P = 0.028, compared to never WS exposure
††Missing education for 2 subjects with ever and 5 subjects with never WS exposure
‡‡Missing income for 128 subjects with ever and 373 subjects with never WS exposure