Table 2.
Demographics of patients in the registry (analysis of 275 patients)a
| Diagnosis | n (%) |
|---|---|
| Definite JDM | 203 (73.8) |
| Probable JDM | 48 (17.5) |
| Definite JPM | 4 (1.5) |
| Probable JPM | 3 (1.1) |
| Other IIMsb | 4 (1.5) |
| Focal myositis | 5 (1.8) |
| MCTD | 8 (2.9) |
| Demographic data, n (%) | In cases of definite or probable JDM or JPM (n = 258) |
|---|---|
| Sex | |
| Girls | 182 (70.5) |
| Boys | 76 (29.5) |
| Ethnicity | |
| White | 207 (80.2) |
| Black—Caribbean | 9 (3.5) |
| Black—African | 7 (2.7) |
| Black—Other | 4 (1.6) |
| Indian | 6 (2.3) |
| Pakistani | 10 (3.9) |
| Bangladeshi | 1 (0.4) |
| Chinese | 0 |
| Other ethnicity | 14 (5.4) |
| Baseline characteristics, cases of definite or probable JDM or JPM | |
|---|---|
| Age at onset, median (IQR), years | 6.3 (3.8–9.6) |
| Time between symptom onset and diagnosis, median (IQR), months | 4 (2–10) |
| Physician’s global assessment at the time of diagnosis, median (IQR)c | 4.8 (2.4–7.0) |
| CHAQ at the time of diagnosis, median (IQR)c | 1.375 (0.625–2.375) |
| CMAS at time of diagnosis, median (IQR)c | 31 (17–47) |
aMedian length of completed follow-up data = 3.0 years, IQR = 1.1–5.0 years. bThese four cases were: two brothers with neonatal-onset multi-system inflammatory disorder that included prominent inflammatory myositis, one post-streptococcal myositis and one viral myositis. cFor those recruited prospectively where baseline measure at the time of diagnosis is available. IQR: interquartile range.