title: Distinct phenotypes in mixed connective tissue disease: subgroups and survival.
abstract: The aim of the present study was to assess the autoantibody profile, dominant clinical symptoms and cluster characteristics of different mixed connective tissue disease (MCTD phenotypes. Two-hundred-and-one patients with MCTD were followed-up longitudinally. Five clinical parameters, Raynaud's phenomenon, pulmonary artery hypertension (PAH), myositis, interstitial lung disease (ILD), erosive arthritis and five auto-antibodies besides anti-U1RNP, antiendothelial cell antibodies (AECA), anti-CCP, anti-cardiolipin (anti-CL), anti-SSA/SSB and IgM rheumatoid factor (RF) were selected for cluster analysis. The mean age of patients was 52.9 ± 12.4 years and the mean follow-up of the disease was 12.5 ± 7.2 years. Patients were classified into three cluster groups. Cluster 1 with 77 patients, cluster 2 with 79 patients and cluster 3 with 45 patients. In cluster 1 the prevalence of PAH (55.8%; p < 0.001), Raynaud's phenomenon (92.2%; p < 0.001) and livedo reticularis (24.6%, p < 0.001) was significantly greater than in cluster 2 and 3. In cluster 2, the incidence of ILD (98.7%; p < 0.001), myositis (77.2%; p < 0.001), and esophageal dysmotility (89.8%; p < 0.001) was significantly greater than that in cluster 1 and 3. In cluster 3, anti-CCP antibodies were present in 31 of 45 patients (68.8%) with erosions. Anti-CCP antibodies were present in 37 of 42 patients (88.0%) with erosions. PAH, angina, venous thrombosis was observed in cluster 1 and pulmonary fibrosis in cluster 2, musculosceletal damage, gastrointestinal symptoms and osteoporotic fractures were most frequent in cluster 3. Cumulative survival assessment indicated cluster 1 patients having the worst prognosis. Cluster analysis is valuable to differentiate among various subsets of MCTD and useful prognostic factor regarding the disease course.
authors.affiliation: Institute of Immunology, Oslo University Hospital, Oslo, Norway. szodoray@gmail.com
authors.forename: P
authors.initials: P
authors.lastname: Szodoray
authors.forename: A
authors.initials: A
authors.lastname: Hajas
authors.forename: L
authors.initials: L
authors.lastname: Kardos
authors.forename: B
authors.initials: B
authors.lastname: Dezso
authors.forename: G
authors.initials: G
authors.lastname: Soos
authors.forename: E
authors.initials: E
authors.lastname: Zold
authors.forename: J
authors.initials: J
authors.lastname: Vegh
authors.forename: I
authors.initials: I
authors.lastname: Csipo
authors.forename: B
authors.initials: B
authors.lastname: Nakken
authors.forename: M
authors.initials: M
authors.lastname: Zeher
authors.forename: G
authors.initials: G
authors.lastname: Szegedi
authors.forename: E
authors.initials: E
authors.lastname: Bodolay
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001168:Arthritis / Q000453:epidemiology; D001323:Autoantibodies / Q000097:blood; D015415:Biomarkers / Q000097:blood; D016009:Chi-Square Distribution; D016000:Cluster Analysis; D018450:Disease Progression; D065627:Familial Primary Pulmonary Hypertension; D005260:Female; D006801:Humans; D006814:Hungary / Q000453:epidemiology; D006976:Hypertension, Pulmonary / Q000453:epidemiology; D015994:Incidence; D008137:Longitudinal Studies; D017563:Lung Diseases, Interstitial / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D008947:Mixed Connective Tissue Disease / Q000145:classification / Q000175:diagnosis / Q000453:epidemiology* / Q000276:immunology / Q000401:mortality; D009220:Myositis / Q000453:epidemiology; D010641:Phenotype; D015995:Prevalence; D011379:Prognosis; D011928:Raynaud Disease / Q000453:epidemiology; D016019:Survival Analysis; D013997:Time Factors
chemical_list: D001323:Autoantibodies; D015415:Biomarkers