THU0243 Standardized mortality ratios and predictors of survival in 215 southern chinese patients with inflammatory myopathies

Objectives To examine the standardized mortality ratios (SMRs) and predictive factors for malignancy in a cohort of southern Chinese patients with inflammatory myopathies (IM). Methods All patients who were diagnosed to have polymyositis (PM), dermatomyositis (DM) or amyotrophic dermatomyositis (ADM) between 2000 and 2010 in the three regional hospitals in Hong Kong were studied. Diagnosis was made according to the Peter and Bohan criteria. Demographic data, clinical presentation, clinical status at last clinic visit and causes of death were retrieved from the hospital database. The sex- and age-adjusted standardized mortality ratios (SMRs) in comparison to the general population for cancer and non-cancer associated DM/ADM and PM were calculated. Cumulative survival of the patients over time was studied by the Kaplan-Meier’s method. Demographic data, presentation at diagnosis (DM vs ADM vs PM), concomitant rheumatic diseases, extra-muscular manifestations were analyzed as predictors for mortality by the Cox regression model. Results 215 patients (64.6% women) with IM were studied (125 DM, 75 PM, 15 ADM). IM was idiopathic in 124 (57.6%) patients, malignancy-related in 52 (24.2%) patients and in 39 (18.1%) patients with concomitant rheumatic diseases. The mean age of disease onset was 51.5±16.3 years. 81 patients (37.6%) died after a mean follow-up period of 4.7±4.6 years. The age- and sex-adjusted SMRs for DM/ADM and PM were 6.4[5.3-7.7], 7.5[5.8-9.6]; (both p Conclusions Idiopathic IM has a poor survival than IM associated with rheumatic diseases. DM/ADM and PM both have significantly increased mortality compared to the general population and to the similar extent. The presence of associated malignancies is a major determinant of survival in dermatomyositis patients but less important in predicting mortality in PM. Disclosure of Interest None Declared