Fixed effect regression analysis
| Model | Coefficient | 95% CI | P value |
| Any periodontal treatment | −€12.03 | −€15.77 to −€8.29 | <0.001 |
| Intensity of periodontal treatment | |||
| Intermediate periodontal treatment | −€8.04 | −€12.80 to −€3.28 | 0.001 |
| Advanced periodontal treatment | −€16.06 | −€21.01 to −€11.11 | <0.001 |