Table 1.
Characteristics of lung caner patients and population controls in Xuanwei, China.
| All | Male | Female | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Cases N (%) | Controls N (%) | P | Cases N (%) | Controls N (%) | P | Cases N (%) | Controls N (%) | P | |
| Categorical variables | |||||||||
| Ethnicity | |||||||||
| Han | 490 (98) | 474 (95) | 257 (99) | 245 (94) | 233 (98) | 229 (96) | |||
| Others | 8 (2) | 24 (5) | 0.0040 | 3 (1) | 15 (6) | 0.0040 | 5 (2) | 9 (4) | 0.28 |
| Literacy | |||||||||
| No | 330 (66) | 363 (73) | 123 (47) | 149 (57) | 207 (87) | 214 (90) | |||
| Yes | 167 (34) | 135 (27) | 0.026 | 136 (52) | 111 (43) | 0.025 | 31 (13) | 24 (10) | 0.32 |
| Coal mine work history | |||||||||
| No | 450 (90) | 474 (95) | 212 (82) | 236 (91) | 238 (100) | 238 (100) | |||
| Yes | 48 (10) | 24 (5) | 0.0033 | 48 (18) | 24 (9) | 0.0023 | 0 (0) | 0 (0) | |
| Number of family members | |||||||||
| <=5 | 300 (60) | 245 (49) | 164 (63) | 139 (53) | 136 (57) | 106 (45) | |||
| >5 | 189 (38) | 239 (48) | 0.0007 | 88 (34) | 108 (42) | 0.044 | 101 (42) | 131 (55) | 0.0058 |
| Lung cancer in first-degree relatives | |||||||||
| No | 460 (92) | 495 (99) | 238 (92) | 259 (100) | <0.0001* | 215 (90) | 234 (98) | ||
| Yes | 38 (8) | 3 (1) | <0.0001* | 22 (8) | 1 (0) | 23 (10) | 4 (2) | 0.0002* | |
| Non-malignant lung disease history | |||||||||
| No | 393 (79) | 461 (93) | 197 (76) | 249 (96) | 196 (82) | 212 (89) | |||
| Yes | 105 (21) | 37 (7) | <0.0001 | 63 (24) | 11 (4) | <0.0001 | 42 (18) | 26 (11) | 0.036 |
| Ever cook | |||||||||
| No | 167 (34) | 170 (34) | 164 (63) | 170 (65) | 3 (1) | 0 (0) | |||
| Yes | 330 (66) | 326 (65) | 0.82 | 95 (37) | 88 (34) | 0.54 | 235 (99) | 238 (100) | 0.25* |
| Location of starting fire | |||||||||
| Indoors | 474 (96) | 465 (94) | 246 (96) | 245 (95) | 228 (96) | 220 (93) | |||
| Outdoors | 20 (4) | 29 (6) | 0.19 | 11 (4) | 13 (5) | 0.68 | 9 (4) | 16 (7) | 0.15 |
| Respondent status | |||||||||
| Personal | 415 (83) | 496 (100) | 224 (86) | 259 (100) | <0.0001* | 191 (80) | 237 (100) | ||
| Next-of-kin | 83 (17) | 2 (0) | <0.0001* | 36 (14) | 1 (0) | 47 (20) | 1 (0) | <0.0001* | |
| Passive smoke exposure& | |||||||||
| No | 29 (5) | 45 (9) | 22 (8) | 34 (13) | 7 (3) | 11 (5) | |||
| Yes | 469 (94) | 453 (91) | 0.053 | 238 (92) | 226 (87) | 0.090 | 231 (97) | 227 (95) | 0.34 |
| Ever smoke cigarettes (Males) | |||||||||
| None | 26 (16) | 34 (24) | |||||||
| Yes | 132 (84) | 110 (76) | 0.12 | ||||||
| Tobacco use (Males) | |||||||||
| Never smoker | 26 (10) | 34 (13) | |||||||
| Other tobacco | 112 (43) | 123 (47) | |||||||
| ≤ 20 pack-year cigarettes | 64 (25) | 81 (31) | |||||||
| >20 pack-year cigarettes | 55 (21) | 21 (8) | <0.0001 | ||||||
| Continuous variables | |||||||||
| Age | |||||||||
| 53±11 | 53±11 | 0.46 | 53±12 | 53±13 | 0.62 | 53±10 | 53±10 | 0.56 | |
| Coal used during lifetime (Tons) | |||||||||
| 190±119 | 179±117 | 0.16 | 183±133 | 172±115 | 0.32 | 197±102 | 188±118 | 0.32 | |
| Years cooking food (Mean ± SD) | |||||||||
| 32±17 | 33±16 | 0.29 | 16±16 | 18±17 | 0.58 | 39±11 | 39±11 | 0.69 | |
| Hours spent at home lifetime (*1000) | |||||||||
| 321±76 | 302±711 | <0.0001 | 312±79 | 292±74 | 0.0038 | 331±71 | 312±67 | 0.0026 | |
*
Fisher’s exact test.
#
Lung disease history includes chronic bronchitis, emphysema, asthma, or tuberculosis.
&
Smoking by any family member who lived with the subject.