TABLE 3.
Predictors of treatment failure in 87 cats with TT4 ≥40 nmol/L after single injection of radioiodine for treatment of hyperthyroidism
| Variable | Failure (n = 52) | Success (n = 3S) | P value | |
|---|---|---|---|---|
| Age (years) | 12.4 [10.4, 14.0] | 12.4 [11.0, 14.0] | .75 | |
| Breed | Purebred | 1 | 1 | .65 |
| Nonpurebred | 51 | 34 | ||
| Stay duration | Long stay | 24 | 16 | .57 |
| Short stay | 28 | 19 | ||
| Dose (MBq) | 74 | 1 | 1 | .07 |
| 111 | 2 | 4 | ||
| 148 | 10 | 13 | ||
| 185 | 35 | 17 | ||
| 250 | 4 | 0 | ||
| Weight (kg) | 3.6 [3.0, 4.3] | 4.2 [3.2, 5.3] | .05 | |
| Weight normalized dose (MBq/kg) | 50.7 [38.5, 62.1] | 33.6 [32.9, 47.4] | .005 | |
| TT4 pretreatment (nmol/L) | 383.8 [251.8, 513.8] | 270.0 [211.0, 372.0] | .003 | |
| TT4 at discharge (nmol/L) | 162.5 [100.75, 258.25] | 62.3 [48.0, 98.1] | <.001 | |
| % change in TT4 | −56.1 [−69.3, −34.0] | −72.3 [−81.8, −61.6] | <.001 | |