| Group | Sex (n/%) | Average Age (years) | Average Course of Disease (years) | |
| Male | Female | |||
| Observation Group | 20 (47.62) | 22 (52.38) | 61.9 ± 2.0 | 3.8 ± 0.5 |
| Control Group | 19 (45.23) | 23 (54.77) | 61.5 ± 5.1 | 3.7 ± 0.6 |
| X2/t | 2.079 | 0.218 | 0.211 | |
| P | >0.05 | >0.05 | >0.05 | |