Table 2.
Covariate-adjusted and propensity-adjusted hazard ratios and 95% confidence intervals from Cox regression models for 1- and 3-year outcomes after landmark date according to PDC levels for RASI and β-blockers during first year post-HF discharge
| 1-year outcomes | 3-year outcomes | |||||
|---|---|---|---|---|---|---|
| All-cause death | HF readmissiona | Death/HF readmission | All-cause death | HF readmissiona | Death/HF readmission | |
| PDC as a categorical variable comparing PDC ≥ 90% vs < 90% (reference group) | ||||||
| Covariate-adjusted Cox modelsb | ||||||
| RASI PDC ≥ 90% | 0.813 (0.679, 0.972) | 0.875 (0.726, 1.054) | 0.908 (0.790, 1.010) | 0.858 (0.766, 0.961) | 0.918 (0.804, 1.047) | 0.907 (0.823, 0.998) |
| p-value | 0.025 | 0.159 | 0.090 | 0.008 | 0.203 | 0.044 |
| Propensity-adjusted Cox modelsc | ||||||
| RASI PDC ≥ 90% | 0.786 (0.660, 0.937) | 0.830 (0.693, 0.993) | 0.852 (0.746, 0.974) | 0.842 (0.754, 0.940) | 0.887 (0.780, 1.008) | 0.871 (0.793, 0.956) |
| p-value | 0.007 | 0.042 | 0.019 | 0.002 | 0.067 | 0.004 |
| Covariate-adjusted Cox modelsb | ||||||
| β-blocker PDC ≥ 90% | 0.757 (0.597, 0.961) | 0.745 (0.591, 0.938) | 0.740 (0.621, 0.882) | 0.876 (0.759, 1.005) | 0.883 (0.754, 1.034) | 0.869 (0.773, 0.978) |
| p-value | 0.022 | 0.013 | 0.0008 | 0.071 | 0.123 | 0.020 |
| Propensity-adjusted Cox modelsc | ||||||
| β-blocker PDC ≥ 90% | 0.723 (0.583, 0.898) | 0.734 (0.592, 0.910) | 0.732 (0.622, 0.860) | 0.852 (0.747, 0.973) | 0.898 (0.774, 1.043) | 0.880 (0.788, 0.982) |
| p-value | 0.003 | 0.005 | 0.0002 | 0.018 | 0.158 | 0.023 |
| PDC as a continuous variable and with each 10% increase in PDC adherence between 60 and 100% | ||||||
| Covariate-adjusted Cox modelsb | ||||||
| RASI | 0.934 (0.825, 0.976) | 0.955 (0.919, 0.994) | 0.946 (0.925, 0.980) | 0.944 (0.920, 0.970) | 0.988 (0.956, 1.014) | 0.964 (0.944, 0.988) |
| Trend p-value | 0.003 | 0.031 | 0.002 | < 0.001 | 0.279 | 0.001 |
| β-blockers | 0.952 (0.922, 0.999) | 0.944 (0.911, 0.983) | 0.942 (0.920, 0.972) | 0.970 (0.946, 0.996) | 0.985 (0.952, 1.003) | 0.974 (0.950, 0.992) |
| Trend p-value | 0.042 | 0.005 | 0.001 | 0.024 | 0.203 | 0.019 |
PDC proportion of days covered, HF heart failure, RASI renin-angiotensin system inhibitor
aThe hazard ratio for HF readmission is the subdistribution HR treating death as a competing risk event
bCox regression models adjusted for sex, age, indigenous status, private insurance, Accessibility Remoteness Index of Australia plus classification, Socio-Economic Indexes for Areas (as the index of Relative Socio-economic Disadvantage), HF hospitalisation(s) prior to index admission and in landmark period, other comorbidities, Charlson comorbidity index, concurrent medications (yes/no), β-blocker adherence (≥ 90%, < 90%) in RASI model and RASI adherence (≥ 90%, < 90%) in β-blocker model
cInverse probability treatment weighted Cox regression models