| Parameters | Event-occurrence group (n = 16) | Event-free group (n = 7) | p Value |
| Age (years) | 65.9±10.2 | 67.0±10.3 | 0.810 |
| Sex (male/female) | 15/1 | 4/3 | 0.067 |
| Obstructive jaundice | 11 | 0 | 0.0046 |
| Abdominal pain | 5 | 0 | 0.147 |
| Pancreatic ductal change diffuse/focal | 11/5 | 2/5 | 0.169 |
| IgG4 (mg/dl) | 545 ± 683 (n = 8) | 543 ± 226 (n = 7) | 0.993 |