Univariate and multivariate Cox regression analysis based on the derivation cohort
| Variables | Univariate analysis | Multivariate analysis | ||
| P value | Crude HR (95% CI) | P value | Adjusted HR (95% CI) | |
| Age (≤60 years) | ||||
| >60 | 0.002 | 0.583 (0.412 to 0.824) | 0.018 | 0.597 (0.390 to 0.914) |
| Sex (male) | ||||
| Female | 0.956 | 1.009 (0.731 to 1.394) | / | / |
| BMI (kg/m2) | ||||
| 18.5–23.9 | ||||
| <18.5 | 0.744 | 1.091 (0.646 to 1.845) | / | / |
| 24.0–27.9 | 0.854 | 0.964 (0.653 to 1.423) | / | / |
| ≥28 | 0.977 | 1.009 (0.562 to 1.811) | / | / |
| Permanent residence | ||||
| Within Guangzhou city limits | ||||
| Outside Guangzhou city limits | 0.166 | 1.323 (0.891 to 1.966) | / | / |
| Payment term | ||||
| Out-of-pocket | ||||
| Health insurance | 0.591 | 0.909 (0.641 to 1.289) | / | / |
| Free medical service | 0.051 | 0.428 (0.183 to 1.002) | / | / |
| Education | ||||
| Primary school or below | ||||
| Junior high school | 0.758 | 1.078 (0.668 to 1.741) | / | / |
| High school or technical secondary school | 0.812 | 1.058 (0.665 to 1.683) | / | / |
| Junior college | 0.343 | 0.719 (0.364 to 1.421) | / | / |
| Bachelor’s degree and above | 0.475 | 0.785 (0.405 to 1.523) | / | / |
| Working status (working) | ||||
| Not working | 0.202 | 0.788 (0.547 to 1.136) | / | / |
| CDM adherence (poor) | ||||
| Good | 0.015 | 0.389 (0.182 to 0.831) | 0.004 | 0.277 (0.114 to 0.671) |
| Primary disease | ||||
| Primary glomerular disease | ||||
| Secondary nephropathy | 0.524 | 1.174 (0.717 to1.920) | 0.319 | 0.746 (0.419 to 1.328) |
| Diabetic nephropathy | 0.020 | 1.733 (1.091 to 2.751) | 0.020 | 2.017 (1.119 to 3.633) |
| Other | 0.464 | 1.253 (0.685 to 2.290) | 0.895 | 0.954 (0.473 to 1.924) |
| Unknown reason | 0.137 | 0.712 (0.455 to 1.113) | 0.104 | 0.649 (0.385 to 1.093) |
| Hb (g/L) (normal) | ||||
| Low | <0.001 | 3.124 (2.236 to 4.366) | 0.001 | 2.011 (1.308 to 3.090) |
| Scr (µmol/L) | <0.001 | 1.008 (1.007 to 1.008) | ||
| eGFR (mL/min/1.73 m2) | <0.001 | 0.901 (0.886 to 0.916) | <0.001 | 0.910 (0.889 to 0.931) |
| CKD stage | ||||
| CKD stage 3 | ||||
| CKD stage 4 | <0.001 | 4.679 (2.971 to 7.370) | / | / |
| CKD stage 5 | <0.001 | 23.522 (14.857 to 37.241) | / | / |
| Urea (≤7.5 mmol/L) | ||||
| >7.5 | <0.001 | 8.778 (3.875 to 19.884) | 0.878 | 0.930 (0.369 to 2.348) |
| UA (µmol/L) (normal) | ||||
| High | 0.020 | 1.665 (1.082 to 2.561) | 0.024 | 1.797 (1.080 to 2.990) |
| CO2CP (≤22 mmol/L) | ||||
| >22 | <0.001 | 2.635 (1.891 to 3.670) | 0.228 | 0.769 (0.501 to 1.179) |
| BLD | ||||
| 0/± | ||||
| 1+ | 0.017 | 1.712 (1.101 to 2.662) | 0.227 | 1.376 (0.820 to 2.309) |
| 2+ | 0.241 | 1.272 (0.851 to 1.902) | 0.921 | 1.024 (0.640 to 1.638) |
| 3~4+ | 0.418 | 1.246 (0.731 to 2.123) | 0.515 | 0.817 (0.444 to 1.503) |
| PRO | ||||
| 0/± | ||||
| 1+ | 0.018 | 2.120 (1.135 to 3.960) | 0.249 | 1.515 (0.748 to 3.069) |
| 2+ | <0.001 | 5.181 (2.938 to 9.139) | 0.007 | 2.466 (1.277 to 4.761) |
| 3~4+ | <0.001 | 7.393 (4.402 to 12.417) | <0.001 | 3.402 (1.838 to 6.295) |
| Hypertension | <0.001 | 3.013 (1.937 to 4.686) | 0.287 | 1.403 (0.752 to 2.617) |
| Diabetes | 0.586 | 1.112 (0.758 to 1.631) | / | / |
| Hyperuricaemia | 0.338 | 1.171 (0.848 to 1.616) | / | / |
| Hyperlipidaemia | 0.701 | 0.935 (0.662 to 1.319) | / | / |
| Urolithiasis | 0.235 | 1.310 (0.839 to 2.046) | / | / |
| Cardiovascular disease | 0.025 | 1.604 (1.062 to 2.423) | 0.014 | 1.875 (1.137 to 3.091) |
| Diuretics | <0.001 | 2.208 (1.497 to 3.256) | 0.389 | 1.236 (0.763 to 2.005) |
| ACEI/ARB | 0.009 | 0.617 (0.430 to 0.884) | 0.148 | 0.725 (0.469 to 1.121) |
| CCB | <0.001 | 3.037 (2.156 to 4.279) | 0.992 | 1.003 (0.605 to 1.661) |
| Alpha-blockers | <0.001 | 3.344 (2.260 to 4.948) | 0.020 | 1.695 (1.086 to 2.646) |
| Beta-blockers | <0.001 | 2.132 (1.513 to 3.006) | 0.018 | 1.651 (1.090 to 2.501) |
| Hypoglycaemic agents | 0.586 | 1.112 (0.758 to 1.631) | / | / |
| Lipid-lowering drugs | 0.531 | 1.128 (0.774 to 1.642) | / | / |
| Urate-lowering drugs | 0.403 | 1.165 (0.815 to 1.665) | / | / |
| Sodium bicarbonate | <0.001 | 2.024 (1.444 to 2.837) | 0.184 | 1.320 (0.877 to 1.987) |
| EPO | <0.001 | 4.768 (3.400 to 6.686) | 0.303 | 1.284 (0.798 to 2.064) |
| Polysaccharide-iron complex | <0.001 | 3.414 (2.389 to 4.878) | 0.397 | 1.265 (0.734 to 2.182) |
| Folic acid | <0.001 | 3.510 (2.256 to 5.460) | 0.574 | 1.178 (0.665 to 2.090) |
| Compound alpha-ketoacid tablets | <0.001 | 2.013 (1.454 to 2.786) | 0.786 | 1.054 (0.722 to 1.537) |
| Calcium supplement | <0.001 | 2.324 (1.647 to 3.278) | 0.044 | 1.538 (1.012 to 2.339) |
| Chinese herbal decoction | 0.047 | 0.582 (0.341 to 0.993) | 0.018 | 0.487 (0.269 to 0.883) |
| Chinese-patent medicines for dispelling turbidity | 0.001 | 1.826 (1.295 to 2.576) | 0.045 | 0.654 (0.432 to 0.990) |
| Chinese-patent medicines for tonifying effects | 0.417 | 0.862 (0.601 to 1.235) | / | / |
| Other Chinese-patent medicines | 0.281 | 0.762 (0.466 to 1.248) | / | / |
| Immunosuppressant | 0.449 | 0.803 (0.454 to 1.419) | / | / |
Variables with p<0.05 in univariate Cox regression were tested for collinearity; Scr and CKD stage were taken out in the multivariate Cox regression analysis due to high collinearity. Crude HR: represented relative HR; adjusted HR: represented adjusted HR, adjusted for age, CDM adherence, primary disease, Hb, eGFR, urea, UA, CO2CP, BLD, PRO, hypertension, cardiovascular disease, diuretics, ACEI/ARB, CCB, alpha-blockers, beta-blockers, sodium bicarbonate, EPO, polysaccharide-iron complex, folic acid, compound alpha-ketoacid tablets, calcium supplement, Chinese herbal decoction and Chinese-patent medicines for dispelling turbidity in the multivariate Cox regression analysis.
ACEI, ACE inhibitor; ARB, angiotensin receptor blocker; BLD, urine latent blood; BMI, body mass index; CCB, calcium channel entry blocker; CDM, chronic disease management; CKD, chronic kidney disease; CO2CP, carbon dioxide combining power; eGFR, estimated glomerular filtration rate; EPO, erythropoietin; Hb, haemoglobin; PRO, urine protein; Scr, serum creatinine; UA, serum uric acid.