Table 7.
Univariate Cox proportional hazards analyses of baseline variables and stepwise multivariate Cox proportional hazards analyses of the effect of treatment and baseline values to determine which variables were associated with time to the composite cardiac endpoint (spontaneous cardiac death, euthanasia due to heart failure, or worsening of congestive heart failure class)
| Variable | Hazard Ratio | 95% Confidence Interval | P‐value |
|---|---|---|---|
| Univariate Cox proportional hazards analyses | |||
| Treatment group | 0.49 | [0.29; 0.85] | 0.011 |
| Age | 1.02 | [0.92; 1.12] | 0.75 |
| Sex: Female vs. Male | 1.62 | [0.97; 2.70] | 0.06 |
| Cavalier King Charles | 0.85 | [0.39; 1.87] | 0.68 |
| Body weight | 0.96 | [0.90; 1.01] | 0.13 |
| Appetite decreased vs. normal | 2.62 | [1.48; 4.66] | 0.0010 |
| Dyspnea: | |||
| 1 vs. 0 | 0.94 | [0.50; 1.76] | 0.92 |
| 2 vs. 0 | 0.95 | [0.48; 1.88] | |
| 3 vs. 0 | 0.59 | [0.14; 2.55] | |
| Exercise tolerance: | |||
| 1 vs. 0 | 0.75 | [0.39; 1.46] | 0.37 |
| 2 vs. 0 | 1.56 | [0.43; 5.60] | |
| Cough: | |||
| 1 vs. 0 | 1.52 | [0.62; 3.71] | 0.73 |
| 2 vs. 0 | 1.66 | [0.69; 4.02] | |
| Syncope yes vs. no | 2.33 | [1.24; 4.40] | 0.0089 |
| Ascites: | |||
| 1 vs. 0 | 1.40 | [0.34; 5.72] | 0.67 |
| 2 vs. 0 | 2.21 | [0.30; 16.23] | |
| Composite clinical score | 1.01 | [0.84; 1.21] | 0.92 |
| Respiratory rate | 1.01 | [1.00; 1.01] | 0.32 |
| Heart rate | 1.01 | [1.00; 1.02] | 0.0043 |
| NYHA class: | |||
| Stage III vs. stage II | 0.65 | [0.37; 1.14] | 0.21 |
| Stage IV vs. stage II | 1.17 | [0.56; 2.47] | |
| IRIS stage: | |||
| 2 vs. 1 | 0.99 | [0.43; 2.32] | 0.92 |
| 3 vs. 1 | 1.51 | [0.47; 4.85] | |
| Pretrial furosemide dosage: | 0.038 | ||
| <4 mg/kg/d vs. no furosemide | 2.28 | [1.13; 4.58] | 0.021 |
| ≥4 mg/kg/d vs. no furosemide | 2.73 | [1.18; 6.32] | 0.019 |
| Pretrial treatment | 1.50 | [0.47; 4.80] | 0.49 |
| Duration of diuretic pretrial treatment | 1.00 | [1.00; 1.00] | 0.090 |
| Duration of heart disease | 1.00 | [1.00; 1.00] | 0.84 |
| Duration of pretrial treatment | 1.00 | [1.00; 1.00] | 0.42 |
| ACE inhibitor pretrial treatment | 1.03 | [0.62; 1.71] | 0.93 |
| Spironolactone pretrial treatment | 1.35 | [0.72; 2.54] | 0.36 |
| Pimobendan pretrial treatment | 1.61 | [0.96; 2.71] | 0.07 |
| Other pretrial treatment | 2.01 | [1.05; 3.88] | 0.037 |
| First diagnosis of congestive heart failure | 0.59 | [0.18; 1.87] | 0.37 |
| Urea | 1.22 | [0.67; 2.22] | 0.52 |
| Creatinine | 1.02 | [0.97; 1.06] | 0.50 |
| Potassium | 0.68 | [0.44; 1.05] | 0.079 |
| Sodium | 0.98 | [0.95; 1.02] | 0.32 |
| Chloride | 0.99 | [0.97; 1.00] | 0.091 |
| Multivariate Cox model with stepwise selection | |||
| Treatment group: Tora vs. Furo | 0.47 | [0.27; 0.82] | 0.0077 |
| Appetite | 2.58 | [1.43; 4.65] | 0.0016 |
| Heart rate | 1.01 | [1.01; 1.02] | 0.0021 |
| Syncope | 2.19 | [1.14; 4.20] | 0.019 |
| Pretrial furosemide dosage: | 0.030 | ||
| <4 mg/kg/d vs. no furosemide | 1.94 | [0.96; 3.94] | 0.067 |
| ≥4 mg/kg/d vs. no furosemide | 3.16 | [1.35; 7.39] | 0.0081 |
P‐values that appear in bold are < 0.05.