Table 1.
The baseline characteristics of the participants classified by liver function.
| Non-liver-injury groupa | Liver injury group | Normal liver function group | Liver dysfunction group | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| n | Valueb | n | Value | Pc | n | Value | n | Value | P | |
| Age | 556 | 50.0 (35.8) | 49 | 43.0 (30.0) | 0.153 | 464 | 50.5 (37.0) | 141 | 46.0 (28.5) | 0.054 |
| Gender | 556 | 49 | 0.429 | 464 | 141 | 0.107 | ||||
| Male | 402 (72.3%) | 38 (77.6%) | 330 (71.1%) | 110 (78.0%) | ||||||
| Female | 154 (27.7%) | 11 (22.4%) | 134 (28.9%) | 31 (22.0%) | ||||||
| Area | 0.000 | 464 | 141 | 0.000 | ||||||
| Qingdao | 179 (32.2%) | 31 (63.3%) | 129 (27.8%) | 81 (57.4%) | ||||||
| Linyi | 377 (67.8%) | 18 (36.7%) | 335 (72.2%) | 60 (42.6%) | ||||||
| BMI, kg/m2 | 551 | 20.8 ± 2.9 | 49 | 21.4 ± 3.0 | 0.133 | 459 | 20.7 ± 2.8 | 141 | 21.1 ± 3.3 | 0.154 |
| Smoking | 556 | 119 (21.4%) | 49 | 10 (20.4%) | 1.000 | 464 | 104 (22.4%) | 141 | 25 (17.7%) | 0.290 |
| Alcohol consumption | 556 | 88 (15.8%) | 49 | 8 (16.3%) | 0.841 | 464 | 69 (14.9%) | 141 | 27 (19.1%) | 0.237 |
| Marital status | 549 | 49 | 0.592 | 457 | 141 | 0.424 | ||||
| Single | 127 (23.1%) | 11 (22.4%) | 110 (24.1%) | 28 (19.9%) | ||||||
| Married | 402 (73.2%) | 38 (77.6%) | 330 (72.2%) | 110 (78.0%) | ||||||
| Widowed | 17 (3.1%) | 0 (0.0%) | 15 (3.3%) | 2 (1.4%) | ||||||
| Divorced | 3 (0.5%) | 0 (0.0%) | 2 (0.4%) | 1 (0.7%) | ||||||
| Education completed | 550 | 48 | 0.001 | 458 | 140 | 0.000 | ||||
| None | 78 (14.2%) | 2 (4.2%) | 76 (16.6%) | 4 (2.9%) | ||||||
| Primary school | 134 (24.4%) | 4 (8.3%) | 112 (24.5%) | 26 (18.6%) | ||||||
| Class VII-IX | 203 (36.9%) | 20 (41.7%) | 164 (35.8%) | 59 (42.1%) | ||||||
| Class X-XII | 92 (16.7%) | 12 (25.0%) | 73 (15.9%) | 31 (22.1%) | ||||||
| Diploma or higher | 43 (7.8%) | 10 (20.8%) | 33 (7.2%) | 20 (14.3%) | ||||||
| History of liver diseasesd | 550 | 6 (1.1%) | 49 | 2 (4.1%) | 0.134 | 458 | 5 (1.1%) | 141 | 3 (2.1%) | 0.400 |
| Diabetes | 554 | 87 (15.7%) | 49 | 13 (26.5%) | 0.051 | 462 | 70 (15.2%) | 141 | 30 (21.3%) | 0.087 |
| Outdoor exercise | 553 | 49 | 0.386 | 461 | 141 | 0.004 | ||||
| Almost none | 24 (4.3%) | 3 (6.1%) | 19 (4.1%) | 8 (5.7%) | ||||||
| <2 h per day | 181 (32.7%) | 20 (40.8%) | 139 (30.2%) | 62 (44.0%) | ||||||
| >2 h per day | 348 (62.9%) | 26 (53.1%) | 303 (65.7%) | 71 (50.4%) | ||||||
Liver injury group had an alanine aminotransferase (ALT) or aspartate aminotransferase (AST) level of higher than two times of the upper limit of normal (ULN); Non-liver-injury group had an ALT and AST level of equal or lower than two times of the ULN. Liver dysfunction had an ALT or AST level of higher than the ULN; Normal liver function group had an ALT and AST level of equal or lower than the ULN. The ULN for ALT and AST is 40 U/L.
Non-normal variables were presented as median (IQR); normal variables were presented as mean ± SD; categorical variables were presented as number of patients in a specific category (percentage).
P was calculated between the non-liver-injury group and liver injury group, and between the normal liver function group and liver dysfunction group. The statistical difference for the non-normal data was tested by a Mann-Whitney U-test; the difference for the normal data was tested by a t-test; the difference for the categorical data was tested by a χ2-test.
The intergroup difference for the history of liver diseases was tested by a Fisher's exact-test. P values were labeled in bold if they were less than 0.05.