Cluster analysis of autoantibodies in 852 patients with systemic lupus erythematosus from a single center.
OBJECTIVE
Associations between autoantibodies and clinical features have been described in systemic lupus erythematosus (SLE). Herein, we aimed to define autoantibody clusters and their clinical correlations in a large cohort of patients with SLE.


METHODS
We analyzed 852 patients with SLE who attended our clinic. Seven autoantibodies were selected for cluster analysis: anti-DNA, anti-Sm, anti-RNP, anticardiolipin (aCL) immunoglobulin (Ig)G or IgM, lupus anticoagulant (LAC), anti-Ro, and anti-La. Two-step clustering and Kaplan-Meier survival analyses were used.


RESULTS
Five clusters were identified. A cluster consisted of patients with only anti-dsDNA antibodies, a cluster of anti-Sm and anti-RNP, a cluster of aCL IgG/M and LAC, and a cluster of anti-Ro and anti-La antibodies. Analysis revealed 1 more cluster that consisted of patients who did not belong to any of the clusters formed by antibodies chosen for cluster analysis. Sm/RNP cluster had significantly higher incidence of pulmonary hypertension and Raynaud phenomenon. DsDNA cluster had the highest incidence of renal involvement. In the aCL/LAC cluster, there were significantly more patients with neuropsychiatric involvement, antiphospholipid syndrome, autoimmune hemolytic anemia, and thrombocytopenia. According to the Systemic Lupus International Collaborating Clinics damage index, the highest frequency of damage was in the aCL/LAC cluster. Comparison of 10 and 20 years survival showed reduced survival in the aCL/LAC cluster.


CONCLUSIONS
This study supports the existence of autoantibody clusters with distinct clinical features in SLE and shows that forming clinical subsets according to autoantibody clusters may be useful in predicting the outcome of the disease. Autoantibody clusters in SLE may exhibit differences according to the clinical setting or population.
From the Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University, Istanbul, Turkey.B. Artim-Esen, MD, Fellow, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; E. Çene, Fellow, Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University; Y. Şahinkaya, MD, Fellow; S. Ertan, MD, Fellow; Ö. Pehlivan, MD, Fellow; S. Kamali, MD, Professor; A. Gül, MD, Professor; L. Öcal, MD, Professor; O. Aral, MD, Professor; M. Inanç, MD, Professor, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University. bahartimesen@gmail.com.
Bahar
B
Artim-Esen
From the Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University, Istanbul, Turkey.B. Artim-Esen, MD, Fellow, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; E. Çene, Fellow, Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University; Y. Şahinkaya, MD, Fellow; S. Ertan, MD, Fellow; Ö. Pehlivan, MD, Fellow; S. Kamali, MD, Professor; A. Gül, MD, Professor; L. Öcal, MD, Professor; O. Aral, MD, Professor; M. Inanç, MD, Professor, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University.
Erhan
E
Çene
From the Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University, Istanbul, Turkey.B. Artim-Esen, MD, Fellow, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; E. Çene, Fellow, Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University; Y. Şahinkaya, MD, Fellow; S. Ertan, MD, Fellow; Ö. Pehlivan, MD, Fellow; S. Kamali, MD, Professor; A. Gül, MD, Professor; L. Öcal, MD, Professor; O. Aral, MD, Professor; M. Inanç, MD, Professor, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University.
Yasemin
Y
Şahinkaya
From the Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University, Istanbul, Turkey.B. Artim-Esen, MD, Fellow, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; E. Çene, Fellow, Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University; Y. Şahinkaya, MD, Fellow; S. Ertan, MD, Fellow; Ö. Pehlivan, MD, Fellow; S. Kamali, MD, Professor; A. Gül, MD, Professor; L. Öcal, MD, Professor; O. Aral, MD, Professor; M. Inanç, MD, Professor, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University.
Semra
S
Ertan
From the Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University, Istanbul, Turkey.B. Artim-Esen, MD, Fellow, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; E. Çene, Fellow, Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University; Y. Şahinkaya, MD, Fellow; S. Ertan, MD, Fellow; Ö. Pehlivan, MD, Fellow; S. Kamali, MD, Professor; A. Gül, MD, Professor; L. Öcal, MD, Professor; O. Aral, MD, Professor; M. Inanç, MD, Professor, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University.
Özlem
Ö
Pehlivan
From the Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University, Istanbul, Turkey.B. Artim-Esen, MD, Fellow, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; E. Çene, Fellow, Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University; Y. Şahinkaya, MD, Fellow; S. Ertan, MD, Fellow; Ö. Pehlivan, MD, Fellow; S. Kamali, MD, Professor; A. Gül, MD, Professor; L. Öcal, MD, Professor; O. Aral, MD, Professor; M. Inanç, MD, Professor, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University.
Sevil
S
Kamali
From the Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University, Istanbul, Turkey.B. Artim-Esen, MD, Fellow, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; E. Çene, Fellow, Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University; Y. Şahinkaya, MD, Fellow; S. Ertan, MD, Fellow; Ö. Pehlivan, MD, Fellow; S. Kamali, MD, Professor; A. Gül, MD, Professor; L. Öcal, MD, Professor; O. Aral, MD, Professor; M. Inanç, MD, Professor, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University.
Ahmet
A
Gül
From the Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University, Istanbul, Turkey.B. Artim-Esen, MD, Fellow, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; E. Çene, Fellow, Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University; Y. Şahinkaya, MD, Fellow; S. Ertan, MD, Fellow; Ö. Pehlivan, MD, Fellow; S. Kamali, MD, Professor; A. Gül, MD, Professor; L. Öcal, MD, Professor; O. Aral, MD, Professor; M. Inanç, MD, Professor, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University.
Lale
L
Öcal
From the Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University, Istanbul, Turkey.B. Artim-Esen, MD, Fellow, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; E. Çene, Fellow, Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University; Y. Şahinkaya, MD, Fellow; S. Ertan, MD, Fellow; Ö. Pehlivan, MD, Fellow; S. Kamali, MD, Professor; A. Gül, MD, Professor; L. Öcal, MD, Professor; O. Aral, MD, Professor; M. Inanç, MD, Professor, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University.
Orhan
O
Aral
From the Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University, Istanbul, Turkey.B. Artim-Esen, MD, Fellow, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University; E. Çene, Fellow, Department of Statistics, Faculty of Arts and Sciences, Yildiz Technical University; Y. Şahinkaya, MD, Fellow; S. Ertan, MD, Fellow; Ö. Pehlivan, MD, Fellow; S. Kamali, MD, Professor; A. Gül, MD, Professor; L. Öcal, MD, Professor; O. Aral, MD, Professor; M. Inanç, MD, Professor, Division of Rheumatology, Department of Internal Medicine, Istanbul Faculty of Medicine, Istanbul University.
Murat
M
Inanç
D000328:Adult; D001323:Autoantibodies / Q000097:blood* / Q000276:immunology; D016000:Cluster Analysis; D005260:Female; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D055815:Young Adult
D001323:Autoantibodies
AUTOANTIBODIES; CLUSTER; DAMAGE; DISEASE PATTERN; SURVIVAL; SYSTEMIC LUPUS ERYTHEMATOSUS