| Gender | Number of cases (%) | Average age (years) |
| Male | 151 (84.36) | 49.79 ± 14.42 |
| Female | 28 (15.64) | 43.57 ± 17.28 |
| χ2 or t value | 169.0391 | 2.0299 |
| P value | 0.0000 | 0.0000 |