Multivariable cox regression analyses of risk factors in the DM/PM patients
| Variables | HR | 95% CI | P value |
|---|---|---|---|
| Dermatomyositis | |||
| Age* | 1.04 | 1.01–1.06 | <0.001 |
| ILD | 1.35 | 0.74–2.48 | 0.319 |
| Respiratory muscle involvement | 2.58 | 1.19–5.58 | 0.016 |
| Malignancy | 3.12 | 1.49–6.58 | 0.003 |
| Polymyositis | |||
| Age* | 1.08 | 1.00–1.16 | 0.044 |
| ILD | 2.47 | 0.18–34.00 | 0.500 |
| ESR | 1.02 | 0.99–1.04 | 0.174 |
*Age: Age at disease onset. Abbreviations: HR: Hazard Ratio; CI: confidence interval; ILD: interstitial lung disease; ESR: erythrocyte sedimentation rate.