Table 5.
Predictors of pneumonia in RA patients by the Cox-hazard model (univariate analysis)
| Hazard ratio | P value | 95% CI | |
|---|---|---|---|
| Demographics | |||
| Age (years) | 1.058 | 0.002 | 1.021–1.095 |
| Gender, male | 1.073 | 0.870 | 0.464–2.480 |
| Laboratory data | |||
| CRP (mg/dl) | 1.321 | <0.0001 | 1.140–1.531 |
| Serum albumin (g/dl) | 0.414 | 0.051 | 0.171–1.004 |
| Serum creatinine (mg/dl) | 1.358 | 0.413 | 0.652–2.828 |
| RA characteristics | |||
| RA duration (years) | 1.002 | 0.927 | 0.968–1.036 |
| HAQ | 1.219 | 0.366 | 0.794–1.871 |
| DAS28 (CRP) | 0.894 | 0.498 | 0.646–1.237 |
| SDAI | 0.970 | 0.281 | 0.919–1.025 |
| CDAI | 0.949 | 0.115 | 0.890–1.013 |
| Comorbidity | |||
| Smoking history | 0.936 | 0.877 | 0.405–2.165 |
| Cardiovascular disease | 1.745 | 0.122 | 0.862–3.533 |
| Metabolic disease | 1.612 | 0.211 | 0.763–3.405 |
| CKD | 1.814 | 0.415 | 0.433–7.592 |
| Autoimmune disease | 0.723 | 0.750 | 0.099–5.299 |
| Interstitial pneumonia | 4.449 | <0.0001 | 2.143–9.237 |
| PPSV23 vaccination | 1.048 | 0.894 | 0.523–2.099 |
| Treatment | |||
| PSL | 1.314 | 0.443 | 0.654–2.643 |
| Dose of prednisolone (mg/day) | 1.117 | 0.102 | 0.978–1.276 |
| MTX | 0.778 | 0.493 | 0.381–1.593 |
| Dose of MTX (mg/week) | 0.962 | 0.634 | 0.821–1.128 |
| TAC | 0.956 | 0.934 | 0.335–2.727 |
| Biologics | 0.544 | 0.088 | 0.270–1.094 |
PPSV23 23-valent pneumococcal polysaccharide vaccine, CRP C-reactive protein, RA rheumatoid arthritis, HAQ Health Assessment Questionnaire Disability Index score, DAS28 Disease Activity Score 28, SDAI simplified disease activity index, CDAI clinical disease activity index, CKD chronic kidney disease, PSL prednisolone, MTX methotrexate, TAC tacrolimus, CI confidence interval