Table 1 Baseline characteristics of the analysis population
|  | All subjects (n = 2,425) | Excluded subjects (n = 648) | Analyzed subjects (n = 1,777) | P value |
|---|---|---|---|---|
Age (years) | ||||
 40–59 | 370 (15.3) | 114 (17.6) | 256 (14.4) | <0.001 |
 60–69 | 847 (34.9) | 172 (26.5) | 675 (38.0) | |
 ≥70 | 1,208 (49.8) | 362 (55.9) | 846 (47.6) | |
Sex | ||||
 Male | 985 (40.6) | 211 (32.6) | 774 (43.6) | <0.001 |
 Female | 1,440 (59.4) | 437 (67.4) | 1,003 (56.4) | |
Occupational categories | ||||
 No occupation | 1,430 (59.0) | 401 (61.9) | 1,029 (57.9) |  |
 Nonmanual | 134 (5.5) | 33 (5.1) | 101 (5.7) | 0.059 |
 Service | 250 (10.3) | 63 (9.7) | 187 (10.5) | |
 Manual | 426 (17.6) | 93 (14.4) | 333 (18.7) | |
 Other | 185 (7.6) | 58 (9.0) | 127 (7.1) | |
Smoking status | ||||
 Never | 1,578 (65.2) | 463 (71.9) | 1,115 (62.7) | <0.001 |
 Past | 587 (24.2) | 127 (19.7) | 460 (25.9) | |
 Current | 256 (10.6) | 54 (8.4) | 202 (11.4) | |
Alcohol consumption | ||||
 Never | 770 (32.1) | 222 (35.6) | 548 (30.8) | <0.001 |
 Every day | 559 (23.3) | 108 (17.3) | 451 (25.4) | |
 Sometimes | 454 (18.9) | 122 (19.6) | 332 (18.7) | |
 Rarely | 617 (25.7) | 171 (27.5) | 446 (25.1) | |
BMI (kg/m2) | ||||
 <25 | 1,134 (63.2) | 220 (63.2) | 1,124 (63.3) | 0.990 |
 ≥25 | 781 (36.8) | 128 (36.8) | 653 (36.7) | |
Past medical history | ||||
 Hypertension | ||||
  No | 1,234 (51.6) | 332 (54.0) | 902 (50.8) | 0.168 |
  Yes | 1,158 (48.4) | 283 (46.0) | 875 (49.2) | |
 Cerebrovascular disease | ||||
  No | 2,277 (95.4) | 583 (95.6) | 1,694 (95.3) | 0.804 |
  Yes | 110 (4.6) | 27 (4.4) | 83 (4.7) | |
 Cardiac disease | ||||
  No | 2,186 (91.5) | 563 (91.8) | 1,623 (91.3) | 0.697 |
  Yes | 204 (8.5) | 50 (8.2) | 154 (8.7) | |
 Hyperlipidemia | ||||
  No | 1,653 (69.3) | 433 (71.0) | 1,220 (68.7) | 0.282 |
  Yes | 734 (30.8) | 177 (29.0) | 557 (31.3) | |
 Diabetic disease | ||||
  No | 2,191 (91.9) | 564 (92.8) | 1,627 (91.6) | 0.348 |
  Yes | 194 (8.1) | 44 (7.2) | 150 (8.4) | |
Subjective outcome, mean (SD) | ||||
 The QuickDASH | 8.9 (11.4) | 9.7 (11.9) | 8.7 (11.2) | 0.046 |
 SF-12 | ||||
  PCS | 31.9 (12.2) | 30.8 (12.1) | 32.2 (12.2) | 0.030 |
  MCS | 45.8 (8.9) | 45.9 (8.3) | 45.8 (9.1) | 0.892 |