Table 3. Stratified Analysis of Unadjusted Hazard Ratios of Structural Recurrence for Coexistent vs Absent Hashimoto Thyroiditis in Cox Proportional Hazards Regression Models.
| Stratification | Hazard ratio (95% CI) | P value | P value for interaction |
|---|---|---|---|
| Age, y | |||
| <45 | 0.76 (0.58-0.98) | .04 | .29 |
| ≥45 | 0.59 (0.41-0.84) | <.001 | |
| Sex | |||
| Female | 0.88 (0.70-1.11) | .27 | .07 |
| Male | 0.47 (0.23-0.94) | .03 | |
| Primary tumor size | |||
| <2 cm | 0.95 (0.73-1.25) | .72 | .06 |
| ≥2 cm | 0.61 (0.43-0.86) | .005 | |
| Extrathyroidal extension | |||
| Absent | 1.08 (0.81-1.44) | .61 | .002 |
| Present | 0.52 (0.38-0.71) | <.001 | |
| Lymph node metastasis | |||
| Absent | 0.73 (0.48-1.12) | .15 | .82 |
| Present | 0.68 (0.53-0.87) | .002 | |
| Extent | |||
| Lobectomy | 0.88 (0.67-1.15) | .35 | .009 |
| Total thyroidectomy | 0.50 (0.35-0.69) | <.001 | |
| Radioactive iodine administration | |||
| Absent | 0.74 (0.59-0.93) | .01 | .55 |
| Present | 0.59 (0.35-0.99) | .046 |