Table 2. The association between depression and mortality risk: Parameter estimates from the primary survival analysis models stratified by type of cancer.
| Parameter | Hazard Ratio | 95% CI | p-value |
|---|---|---|---|
| Breast cancer | |||
| Major depression diagnosis | 1.42 | 1.15, 1.75 | 0.001 |
| Years between cancer diagnosis and depression screeninga | 0.96 | 0.46, 1.99 | 0.905 |
| Age at cancer diagnosisb | 0.28 | 0.19, 0.41 | <0.001 |
| Age at cancer diagnosisb squared | 1.13 | 1.10, 1.17 | <0.001 |
| SIMDb | 1.09 | 1.05, 1.14 | <0.001 |
| Therapy intent (palliative v curative) | 7.80 | 6.57, 9.26 | <0.001 |
| Years between cancer diagnosis and depression screeninga × Age at cancer diagnosisb | 1.17 | 0.91, 1.52 | 0.218 |
| Years between cancer diagnosis and depression screeninga × Age at cancer diagnosisb squared | 0.98 | 0.96, 1.01 | 0.157 |
| Years between cancer diagnosis and depression screeninga × SIMDb | 1.02 | 0.99, 1.05 | 0.123 |
| Years between cancer diagnosis and depression screeninga × therapy intent (palliative v curative) | 0.74 | 0.65, 0.84 | <0.001 |
| Colorectal cancer | |||
| Major depression diagnosis | 1.47 | 1.11, 1.94 | 0.007 |
| Years between cancer diagnosis and depression screeningc | 1.06 | 0.88, 1.27 | 0.553 |
| Age at cancer diagnosisb | 1.14 | 1.06, 1.24 | <0.001 |
| Sex (male v female) | 1.13 | 0.98, 1.29 | 0.087 |
| SIMDb | 1.02 | 0.97, 1.08 | 0.378 |
| Therapy intent (palliative v curative) | 7.39 | 6.10, 8.94 | <0.001 |
| Years between cancer diagnosis and depression screeningc × Age at cancer diagnosisb | 1.00 | 0.98, 1.03 | 0.793 |
| Years between cancer diagnosis and depression screeningc × SIMDb | 1.01 | 0.99, 1.03 | 0.444 |
| Years between cancer diagnosis and depression screeningc × therapy intent (palliative v curative) | 0.79 | 0.71, 0.87 | <0.001 |
| Gynaecological cancer | |||
| Major depression diagnosis | 1.36 | 1.08, 1.71 | 0.010 |
| Years between cancer diagnosis and depression screeningd | 1.00 | 0.95, 1.06 | 0.896 |
| Years between cancer diagnosis and depression screeninge | 1.00 | 0.98, 1.02 | 0.997 |
| Age at cancer diagnosisb | 1.18 | 1.11, 1.26 | <0.001 |
| SIMDb | 1.04 | 0.99, 1.09 | 0.148 |
| Therapy intent (palliative v curative) | 5.03 | 4.14, 6.11 | <0.001 |
| Years between cancer diagnosis and depression screeningd × Age at cancer diagnosisb | 1.00 | 0.99, 1.01 | 0.794 |
| Years between cancer diagnosis and depression screeninge × Age at cancer diagnosisb | 1.00 | 1.00, 1.00 | 0.761 |
| Years between cancer diagnosis and depression screeningd × SIMDb | 1.00 | 0.99, 1.01 | 0.487 |
| Years between cancer diagnosis and depression screeninge × SIMDb | 1.00 | 1.00, 1.00 | 0.407 |
| Years between cancer diagnosis and depression screeningd × therapy intent (palliative v curative) | 0.96 | 0.88, 1.03 | 0.252 |
| Years between cancer diagnosis and depression screeninge × therapy intent (palliative v curative) | 1.01 | 0.98, 1.05 | 0.425 |
| Lung cancer | |||
| Major depression diagnosis | 1.39 | 1.24, 1.56 | <0.001 |
| Years between cancer diagnosis and depression screeninga | 0.81 | 0.62, 1.06 | 0.133 |
| Age at cancer diagnosisb | 1.09 | 1.04, 1.15 | <0.001 |
| Sex (male v female) | 1.13 | 1.05, 1.21 | 0.001 |
| SIMDb | 1.02 | 1.00, 1.05 | 0.075 |
| Therapy intent (palliative v curative) | 2.16 | 1.93, 2.41 | <0.001 |
| Years between cancer diagnosis and depression screeninga × Age at cancer diagnosisb | 1.03 | 1.00, 1.08 | 0.078 |
| Years between cancer diagnosis and depression screeninga × SIMDb | 1.00 | 0.98, 1.02 | 0.819 |
| Years between cancer diagnosis and depression screeninga × therapy intent (palliative v curative) | 0.69 | 0.63, 0.75 | <0.001 |
| Prostate cancer | |||
| Major depression diagnosis | 1.76 | 1.08, 2.85 | 0.022 |
| Years between cancer diagnosis and depression screeningc | 0.76 | 0.47, 1.22 | 0.254 |
| Age at cancer diagnosisb cubed | 0.93 | 0.89, 0.97 | 0.001 |
| Age at cancer diagnosisb cubed × loge(age at cancer diagnosisb) | 1.03 | 1.01, 1.05 | <0.001 |
| SIMDb | 1.17 | 1.06, 1.30 | 0.003 |
| Therapy intent (palliative v curative) | 3.11 | 2.01, 4.82 | <0.001 |
| Years between cancer diagnosis and depression screeningc × age at cancer diagnosisb cubed | 1.01 | 1.00, 1.02 | 0.080 |
| Years between cancer diagnosis and depression screeningc × age at cancer diagnosisb cubed × loge(age at cancer diagnosisb) | 1.01 | 1.00, 1.02 | 0.080 |
| Years between cancer diagnosis and depression screeningc × SIMDb | 0.98 | 0.96, 1.00 | 0.027 |
| Years between cancer diagnosis and depression screeningc × therapy intent (palliative v curative) | 0.98 | 0.90, 1.06 | 0.551 |
The hazard ratios of primary importance (shown in bold) relate to the comparison between those patients with and without major depression. The hazard ratios for other variables and interactions between pairs of such variables are for (sometimes) transformed covariates that make up the fractional polynomial model used for covariate adjustment. The transformations are
a
loge (X+0.1);
b
X/10;
c
X+0.1;
d
(X+0.1)^2 and
e
([X+0.1]^2)×loge[X+0.1].