title: Survival analysis of patients with dermatomyositis and polymyositis: analysis of 192 Chinese cases.
abstract: To estimate the mortality rate and identify factors predicting survival in patients with polymyositis (PM) and dermatomyositis (DM). The medical records of 192 PM/DM patients who were treated at Chang Gung Memorial Hospital from 1999 through 2008 were retrospectively reviewed. The Taiwan National Death Registry (1999-2008) was used to obtain their survival status. Thirty-one (16.1%) of the 192 patients with PM/DM had an associated malignancy; 41 (21.4%) had interstitial lung disease (ILD). During the follow-up period, 55 (28.6%) patients died and the overall cumulative survival rate was 79.3% at 1 year, 75.7% at 2 years, 69.9% at 5 years, and 66.2% at 10 years. In univariate analysis, older age at PM/DM onset, anemia, thrombocytopenia, leukopenia, diabetes mellitus, ILD, cancer, and non-use of azathioprine were associated with higher mortality (p = 0.0172, 0.0484, <0.0001, 0.0008, 0.0001, 0.0036, 0.0010, and 0.0019, respectively). In multivariate Cox regression analysis, thrombocytopenia (hazard ratio [HR] 4.94, 95% confidence interval [CI] 2.60-9.37, p < 0.0001), diabetes mellitus (HR 2.57, 95% CI 1.38-4.80, p < 0.0001), cancer (HR 2.30, 95% CI 1.26-4.22, p = 0.0030), and ILD (HR 1.98, 95% CI 1.11-3.51, p = 0.0182) were positively associated with mortality. Use of azathioprine (HR 0.35, 95% CI 0.16-0.74, p = 0.0064) was negatively associated with mortality. This study confirmed the high mortality rate (28.6%) in PM/DM patients. Survival time was significantly reduced in patients with thrombocytopenia, diabetes mellitus, ILD, and cancer patients than in those without these conditions.
authors.affiliation: Division of Allergy, Immunology and Rheumatology, Chang Gung Memorial Hospital, 5, Fu-Shin St., Kuei-Shan (333), Tao-Yuan, Taiwan. gout@adm.cgmh.org.tw
authors.forename: Kuang-Hui
authors.initials: KH
authors.lastname: Yu
authors.forename: Yeong-Jian Jan
authors.initials: YJ
authors.lastname: Wu
authors.forename: Chang-Fu
authors.initials: CF
authors.lastname: Kuo
authors.forename: Lai-Chu
authors.initials: LC
authors.lastname: See
authors.forename: Yu-Ming
authors.initials: YM
authors.lastname: Shen
authors.forename: Hsiao-Chun
authors.initials: HC
authors.lastname: Chang
authors.forename: Shue-Fen
authors.initials: SF
authors.lastname: Luo
authors.forename: Huei-Huang
authors.initials: HH
authors.lastname: Ho
authors.forename: I-Jung
authors.initials: IJ
authors.lastname: Chen
mesh_terms: D000328:Adult; D000368:Aged; D018501:Antirheumatic Agents / Q000627:therapeutic use; D001379:Azathioprine / Q000627:therapeutic use; D003882:Dermatomyositis / Q000188:drug therapy / Q000401:mortality*; D048909:Diabetes Complications; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D017563:Lung Diseases, Interstitial / Q000150:complications; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications; D017285:Polymyositis / Q000188:drug therapy / Q000401:mortality*; D011379:Prognosis; D012042:Registries; D012189:Retrospective Studies; D015996:Survival Rate; D013624:Taiwan / Q000453:epidemiology; D013921:Thrombocytopenia / Q000150:complications
chemical_list: D018501:Antirheumatic Agents; D001379:Azathioprine