Publications

We report a longitudinal observational cohort of idiopathic inflammatory myositis (IIM)
focusing on the long-term clinical outcome and associated parameters. Methods: IIM patients were
classified as per Bohan and Peter criteria. In those with ≥ 24 months of follow-up; the treatment
response, functional outcomes, and damage at last follow-up were recorded. Complete clinical re-
sponse and clinical remission as defined by Oddis et al., was used to define outcomes at last fol-
low-up. Results: The cohort consists of 175 patients, mean age 40.9 (+12.6) years, M:F 1:3.3; and
the major subsets were dermatomyositis (44.6%), overlap myositis (25.7%), antisynthetase syn-
drome (6.3%), polymyositis (14.3%), and juvenile DM/OM (8.6%). Ninety-four patients have followed
up for 24 months or more, with the median (IQR) of 65(35,100.7) months. Of them, 74.1% and
11.8% had complete and partial clinical responses respectively at the last follow-up. In our cohort
40.2% were off-steroids and 13.8% were in clinical remission at the last follow-up. Complete clinical
response was associated with better functional outcomes and lesser damage as determined by
HAQ-DI of 0[OR10.9; 95%CI (3.3,160)], MRS [OR 3.2; 95%CI (1.4,7.3)] and lesser MDI [OR 1.7; 95%
CI (1.1,2.7)] respectively as compared to partial response (unadjusted analysis). Baseline parameters
and IIM subsets did not significantly influence the functional outcome and damage. The mortality
rate in our cohort is 24/175 (13.7%), the disease-specific mortality rate being 9.1%. Large majority
of deaths were early, associated with active disease. Conclusion: We report good long-term out-
comes in all major myositis subsets. Partial clinical response to treatment is associated with worse
functional outcomes and damage accrual. Death occurs early in association with active disease.