Table 1.
Baseline characteristics of patients in both groups.
| Variable | Original cohort | P | Matched cohort | P | Standard difference | ||
|---|---|---|---|---|---|---|---|
| MOR high expression group (n=145) | MOR low expression group (n=136) | MOR high expression group (n=118) | MOR low expression group (n=118) | ||||
| Age (media-IQR, year) | 56 (45-63) | 55 (46-67) | 0.726 | 56 (46-62) | 56 (46-66) | 0.684 | 3.15 |
| Gender (n, %) | |||||||
| Female | 48 (33.2%) | 44 (32.0%) | 0.893 | 42 (35.6%) | 43 (36.4%) | 0.892 | – |
| Male | 97 (66.8%) | 92 (68.0%) | 76 (64.4%) | 75 (63.6%) | – | ||
| BMI kg/m2, (median-IQR) | 23.5 (21.3-24.3) | 22.6 (20.8-24.8) | 22.3 (21.3-23.9) | 23.0 (20.7-24.3) | – | ||
| ASA (n, %) | 0.881 | 0.948 | 2.58 | ||||
| I | 94 (65.2%) | 89 (65.4%) | 76 (64.4%) | 74 (62.7%) | – | ||
| II | 38 (26.4%) | 37 (27.2%) | 35 (29.6%) | 36 (30.5%) | – | ||
| III | 13 (8.4%) | 10 (7.4%) | 7 (6%) | 8 (6.8%) | – | ||
| Patients enrolled | 0.969 | 0.915 | – | ||||
| 2015 | 50 (34.5%) | 46 (33.6%) | 39 (33.1%) | 41 (34.7%) | |||
| 2016 | 47 (32.4%) | 46 (33.8%) | 38 (32.2%) | 39 (33.1%) | |||
| 2017 | 48 (33.1%) | 44 (32.6%) | 41 (34.7%) | 38 (32.2%) | |||
| CCI (n, %) | 0.946 | 0.861 | 2.89 | ||||
| 0 | 91 (62.8%) | 87 (63.9%) | 79 (66.9%) | 75 (63.5%) | – | ||
| 1 | 43 (29.7%) | 38 (27.8%) | 30 (25.4%) | 33 (27.9%) | |||
| ≧2 | 11 (7.5%) | 11 (8.3%) | 9 (7.7%) | 10 (8.9%) | |||
| Tumor differentiation (n, %) | 0.727 | 0.893 | 3.26 | ||||
| Well-moderate | 53 (36.8%) | 47 (34.8%) | 43 (36.4%) | 44 (37.3%) | – | ||
| Poor | 92 (63.2%) | 89 (65.2%) | 75 (63.6%) | 74 (62.7%) | – | ||
| T stage (n, %) | 0.542 | 0.404 | |||||
| 1 | 35 (23.9%) | 31 (22.8%) | 30 (25.4%) | 29 (24.6%) | – | ||
| 2 | 95 (65.7%) | 85 (62.6%) | 80 (67.8%) | 75 (63.6%) | – | ||
| 3 | 15 (10.4%) | 20 (14.6%) | 8 (6.8%) | 14 (11.8%) | – | ||
| N stage (n, %) | 0.914 | 0.836 | |||||
| 0 | 60 (41.2%) | 55 (40.5%) | 54 (45.7%) | 52 (44.1%) | – | ||
| 1 | 56 (38.7%) | 51 (37.6%) | 51 (43.2%) | 50 (42.4%) | – | ||
| 2 | 29 (20.1%) | 30 (21.9%) | 13 (11.1%) | 16 (13.5%) | – | ||
| AJCC 8th edition TNM stage (n, %) | 0.766 | 0.392 | 4.15 | ||||
| I | 70 (48.8%) | 63 (46.5%) | 54 (45.7%) | 52 (44.1%) | – | ||
| II | 56 (38.7%) | 51 (37.9%) | 52 (44.1%) | 47 (39.8%) | – | ||
| III | 19 (12.5%) | 22 (15.6%) | 12 (10.2%) | 19 (16.1%) | – | ||
| Tumor size (n, %) | 0.757 | 0.613 | 3.69 | ||||
| ≤2 cm | 110 (75.8%) | 101 (74.2%) | 98 (83.1%) | 95 (80.5%) | – | ||
| >2 cm | 35 (24.2%) | 35 (25.8%) | 20 (16.9%) | 23 (19.5%) | – | ||
| Surgery type (n, %) | 0.660 | 0.628 | 3.54 | ||||
| Pancreaticoduodenectomy | 82 (56.7%) | 74 (54.7%) | 71 (60.2%) | 68 (57.6%) | – | ||
| Distal pancreatectomy | 46 (31.4%) | 41 (30.0%) | 34 (28.8%) | 32 (27.1%) | – | ||
| Total pancreatectomy | 17 (11.9%) | 21 (15.3%) | 13 (11.0%) | 18 (15.3%) | – | ||
| Tumor location (n, %) | 0.446 | 0.777 | 4.56 | ||||
| Head of pancreas | 99 (68.5%) | 87 (64.2%) | 83 (70.3%) | 81 (68.6%) | |||
| Tail of pancreas | 46 (31.5%) | 49 (35.8%) | 35 (29.7%) | 37 (31.4%) | |||
| Estimated blood loss (n, %) | 0.739 | 0.757 | – | ||||
| ≤ 400 ml | 106 (73.5%) | 97 (71.6%) | 92 (77.9%) | 90 (76.3%) | – | ||
| > 400 ml | 39 (26.5%) | 39 (28.4%) | 26 (22.1%) | 28 (23.7%) | – | ||
| Blood transfusion | 0.858 | 0.678 | – | ||||
| No | 131(90.5%) | 122 (89.7%) | 104 (88.1%) | 106 (89.8%) | |||
| Yes | 14 (9.5%) | 14 (10.3%) | 14 (11.9%) | 12 (10.2%) | |||
| Postoperative chemotherapy (n, %) | 0.689 | 0.619 | 5.21 | ||||
| Yes | 122 (84.4%) | 112 (82.6%) | 97 (82.2%) | 94 (79.6%) | – | ||
| no | 23 (15.6%) | 24 (17.4%) | 21 (17.8%) | 24 (20.4%) | – | ||
BMI, Body Mass Index; IQR, Inter Quartile Range; ASA, American Society of Anesthesiologists score; CCI, Charlson Comorbidity Index; AJCC 8th TNM stage, American Joint Committee on Cancer the 8th edition; MOR, Mu-Opioids Receptor.