The standardized mortality ratio (SMR), life expectancy (LE) and years of life lost (YLL)
| Overall (n=280) | Females (n=201) | Males (n=79) | |
|---|---|---|---|
| Dermatomyositis | 226 | 163 | 63 |
| Death number | 55 | 37 | 18 |
| SMR (95% CI) | 9.0 (6.8–11.2) | 12.0 (6.8–11.2) | 6.0 (3.2–8.7) |
| LE of general population (years) | – | 80.8 | 75.8 |
| LE of DM patients (years) | – | 43.3 | 47.4 |
| YLL (years) | – | 37.5 8 | 28.4 |
| Polymyositis | 54 | 38 | 16 |
| Death number | 11 | 8 | 3 |
| SMR (95% CI) | 5.0 (2.4–7.5) | 4.2 (1.3–7.2) | 9.3 (-1.2–19.8) |
| LE of general population (years) | – | 80.8 | 75.8 |
| LE of PM patients (years) | – | 56.5 | 63.8 |
| YLL (years) | – | 24.3 | 12.0 |
Abbreviations: DM: dermatomyositis; SMR: standardised mortality ratio; CI: confidence interval; LE: life expectancy; YLL: years of life lost; PM: polymyositis.