Factors affecting total treatment costs (using the national unit costs) and marginal effect of covariates (n=2738)
| Covariate | Coefficient | SE | p>z | 95% CI | Marginal effect* in euros (95% CI) |
|---|---|---|---|---|---|
| Age | −0.003 | 0.004 | 0.39 | −0.01 to 0.00 | −0.58 (−1.91 to 0.75) |
| Gender, male | −0.269 | 0.088 | 0.00 | −0.44 to −0.10 | −48.53 (−80.35 to −16.71)† |
| CHD | 0.069 | 0.123 | 0.57 | −0.17 to 0.31 | 12.57 (−32.17 to 57.30) |
| Angina | 0.313 | 0.119 | 0.01 | 0.08 to 0.55 | 61.27 (10.91 to 111.62)† |
| MI | 0.068 | 0.127 | 0.59 | −0.18 to 0.32 | 12.52 (−34.11 to 59.15)) |
| Diabetes | 0.282 | 0.104 | 0.01 | 0.08 to 0.49 | 54.70 (11.51 to 97.89)† |
| Hypertension | 0.124 | 0.124 | 0.32 | −0.12 to 0.37 | 23.21 (−24.18 to 70.60) |
| Other bleed | −1.109 | 1.100 | 0.31 | −3.27 to 1.05 | −119.90 (−248.04 to 8.24) |
| GI bleed | 0.476 | 0.838 | 0.57 | −1.17 to 2.12 | 108.81 (−362.56 to 580.19) |
| Intracranial bleed | −2.923 | 1.607 | 0.07 | −6.07 to 0.23 | −169.42 (−202.92 to −135.92)† |
| ICH | 0.175 | 1.536 | 0.91 | −2.83 to 3.18 | 34.19 (−606.32 to 674.71) |
| Stroke | −0.065 | 0.132 | 0.62 | −0.32 to 0.19 | −11.30 (−55.47 to 32.87) |
| TIA | 0.207 | 0.137 | 0.13 | −0.06 to 0.48 | 40.04 (−16.48 to 96.56) |
| CHF | −0.090 | 0.107 | 0.40 | −0.30 to 0.12 | −15.80 (−52.01 to 20.41) |
| Thromboembolism | 0.051 | 0.492 | 0.92 | −0.91 to 1.02 | 9.41 (−171.97 to 190.78) |
| PVD | 0.125 | 0.169 | 0.46 | −0.21 to 0.46 | 23.66 (−42.31 to 89.64) |
| Atherosclerosis of aorta | 1.008 | 1.094 | 0.36 | −1.14 to 3.15 | 310.61 (−737.32 to 1358.54) |
| Neoplasm | 0.926 | 0.409 | 0.02 | 0.13 to 1.73 | 269.58 (−86.92 to 626.08)† |
| Liver disease | −0.390 | 1.103 | 0.72 | −2.55 to 1.77 | −57.74 (−319.54 to 204.07) |
| Kidney disease | 1.077 | 0.736 | 0.14 | −0.37 to 2.52 | 344.51 (−408.13 to 1097.14) |
| TTR classification (compared with no warfarin use) | |||||
| TTR<40% | 2.264 | 0.163 | 0.00 | 1.95 to 2.58 | 551.52 (369.17 to 733.87)† |
| 40≤TTR<60% | 2.466 | 0.173 | 0.00 | 2.13 to 2.81 | 689.86 (452.71 to 927.02)† |
| 60%≤TTR<70% | 2.319 | 0.170 | 0.00 | 1.99 to 2.65 | 586.36 (386.17 to 786.54)† |
| 70%≤TTR<80% | 2.227 | 0.160 | 0.00 | 1.91 to 2.54 | 529.07 (358.82 to 699.33)† |
| TTR≥80% | 2.019 | 0.122 | 0.00 | 1.78 to 2.26 | 417.90 (318.24 to 517.56)† |
| Inpatient days | −0.001 | 0.001 | 0.29 | 0.00 to 0.00 | −0.21 (−0.6 to 0.18) |
| Follow-up time (days) | 0.002 | 0.001 | 0.05 | 0.00 to 0.00 | 0.31 (−0.01 to 0.62) |
| Use of home nursing services | 0.079 | 0.105 | 0.45 | −0.13 to 0.28 | 14.40 (−23.81 to 52.61) |
| Intercept | 3.727 | 0.444 | 0.00 | 2.86 to 4.60 | |
*Estimated as a change from the base level at mean values of covariates except for follow-up time, which was fixed at 365 days.
†Statistically significant marginal effect.
CHD, coronary heart disease; CHF, congestive heart failure; GI, gastrointestinal; ICH, intracerebral haemorrhage; MI, myocardial infarction; PVD, peripheral vascular disease; TIA, transient ischaemic attack; TTR, time in therapeutic range.