Table 4.
Summary of Cox regressions on the interaction between low income and medical risk factors of death from renal disease in the USA
| HR (SE) | 95% CI | P | HR (SE) | 95% CI | P | |
|---|---|---|---|---|---|---|
| Model a (main effects) | Model b (interactions) | |||||
| Model 1 | ||||||
| Race (Black) | 2.03 (0.86) | 0.87–4.75 | 0.099 | 2.04 (0.86) | 0.87–4.74 | 0.097 |
| Age (years) | 1.09 (0.02) | 1.06–1.13 | 0.000 | 1.09 (0.02) | 1.05–1.12 | 0.000 |
| Sex (women) | 0.40 (0.26) | 0.11–1.50 | 0.169 | 0.45 (0.27) | 0.14–1.49 | 0.186 |
| SES (Low Income) | 0.80 (0.49) | 0.23–2.74 | 0.717 | 1.84 (1.45) | 0.38–9.03 | 0.442 |
| Smoking | 3.42 (1.90) | 1.11–10.50 | 0.033 | 3.46 (1.78) | 1.23–9.75 | 0.020 |
| Drinking | 0.13 (0.08) | 0.04–0.44 | 0.002 | 0.15 (0.07) | 0.06–0.41 | 0.000 |
| Exercise | 0.78 (0.17) | 0.50–1.19 | 0.239 | 0.81 (0.16) | 0.54–1.20 | 0.283 |
| SRH (poor) | 2.14 (1.00) | 0.83–5.48 | 0.112 | 1.96 (0.85) | 0.82–4.69 | 0.125 |
| Depressive symptoms | 1.46 (0.25) | 1.04–2.06 | 0.031 | 1.46 (0.26) | 1.02–2.08 | 0.040 |
| DM | 7.35 (3.88) | 2.53–21.30 | 0.000 | 19.57 (17.64) | 3.18–120.25 | 0.002 |
| DM × SES | – | – | – | 0.20 (0.19) | 0.03–1.29 | 0.090 |
| Model 2 | ||||||
| Race (Black) | 1.75 (0.80) | 0.70–4.41 | 0.227 | 1.80 (0.82) | 0.72–4.51 | 0.202 |
| Age (years) | 1.08 (0.02) | 1.05–1.11 | 0.000 | 1.08 (0.01) | 1.05–1.11 | 0.000 |
| Sex (women) | 0.39 (0.25) | 0.11–1.44 | 0.154 | 0.42 (0.26) | 0.13–1.43 | 0.162 |
| SES (low income) | 0.60 (0.46) | 0.13–2.77 | 0.508 | 3.56 (3.19) | 0.59–21.58 | 0.163 |
| Smoking | 3.66 (2.06) | 1.18–11.38 | 0.026 | 3.77 (2.09) | 1.24–11.49 | 0.021 |
| Drinking | 0.13 (0.08) | 0.03–0.48 | 0.003 | 0.13 (0.08) | 0.03–0.48 | 0.003 |
| Exercise | 0.80 (0.17) | 0.53–1.23 | 0.304 | 0.80 (0.17) | 0.52–1.23 | 0.295 |
| SRH (poor) | 2.33 (1.11) | 0.89–6.09 | 0.083 | 2.29 (1.02) | 0.94–5.60 | 0.068 |
| Depressive Symptoms | 1.54 (0.23) | 1.15–2.07 | 0.005 | 1.60 (0.26) | 1.16–2.20 | 0.005 |
| HTN | 4.28 (2.83) | 1.13–16.23 | 0.033 | 19.30 (18.48) | 2.81–132.72 | 0.003 |
| HTN × SES | – | – | – | 0.09 (0.10) | 0.01–0.81 | 0.033 |
| Model 3 | ||||||
| Race (Black) | 1.82 (0.91) | 0.67–4.98 | 0.235 | 2.03 (0.90) | 0.83–4.95 | 0.117 |
| Age (years) | 1.10 (0.02) | 1.07–1.13 | 0.000 | 1.10 (0.02) | 1.07–1.13 | 0.000 |
| Sex (women) | 0.38 (0.25) | 0.10–1.40 | 0.143 | 0.46 (0.25) | 0.15–1.40 | 0.166 |
| SES (low income) | 0.76 (0.48) | 0.21–2.72 | 0.662 | 2.40 (2.22) | 0.37–15.49 | 0.350 |
| Smoking | 3.34 (1.89) | 1.07–10.41 | 0.038 | 3.75 (2.17) | 1.17–12.01 | 0.027 |
| Drinking | 0.14 (0.08) | 0.04–0.42 | 0.001 | 0.16 (0.07) | 0.06–0.41 | 0.000 |
| Exercise | 0.82 (0.16) | 0.55–1.22 | 0.322 | 0.85 (0.16) | 0.59–1.24 | 0.391 |
| SRH (poor) | 2.56 (1.17) | 1.02–6.44 | 0.046 | 2.26 (0.85) | 1.06–4.82 | 0.035 |
| Depressive symptoms | 1.49 (0.18) | 1.17–1.91 | 0.002 | 1.50 (0.19) | 1.17–1.93 | 0.002 |
| Obesity | 2.80 (1.60) | 0.89–8.82 | 0.078 | 11.33 (11.68) | 1.42–90.38 | 0.023 |
| Obesity × SES | – | – | – | 0.10 (0.11) | 0.01–0.91 | 0.041 |
CI, confidence interval; DM; diabetes, HR, hazard ratio; HTN; hypertension; SE, standard error; SES, socioeconomic status; SRH; self‐rated health.