Coexistent malignant conditions in rheumatoid arthritis - A population-based cross-sectional study.
OBJECTIVE
The aim of this study was to evaluate if association exist between rheumatoid arthritis and malignant diseases.


METHODS
A cross-sectional study was conducted comparing rheumatoid arthritis patients with age and gender matched controls regarding the proportion of patients with comorbid malignant conditions. Chi-square tests and t-tests were used for univariate analysis. A logistic regression model was used for multivariate analysis. The study was performed utilising the medical database of Clalit Health Services.


RESULTS
The study group included 11 782 rheumatoid arthritis patients and 57 973 controls. The total proportion of malignancies was significantly higher in the study group than in the control group (21.4% vs 11.2%; P<.001). The disease for which there was the strongest association among patients with rheumatoid arthritis was non-Hodgkin's lymphoma (1.1% vs 0.6%; P<.01). After multivariate analysis, lung cancer was not found to be significantly associated with rheumatoid arthritis.


CONCLUSIONS
Rheumatoid arthritis is associated with several malignant disorders, in particular non-Hodgkin's lymphoma. Appropriate measures for non-Hodgkin's lymphoma screening in this patient population should be considered.
Department of Medicine 'T', Sheba Medical Center, Tel-Hashomer, Israel.|Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel.
Amir
A
Dagan
Department of Medicine 'T', Sheba Medical Center, Tel-Hashomer, Israel.|Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel.
Gad
G
Segal
Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel.|Department of Medicine 'B', Zabludowicz Center for Autoimmune Diseases, Sheba Medical Center, Tel-Hashomer, Israel.
Shmuel
http://orcid.org/0000-0002-1748-4297
S
Tiosano
Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel.|Department of Medicine 'B', Zabludowicz Center for Autoimmune Diseases, Sheba Medical Center, Tel-Hashomer, Israel.
Abdulla
A
Watad
Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel.|Department of Medicine 'B', Zabludowicz Center for Autoimmune Diseases, Sheba Medical Center, Tel-Hashomer, Israel.
Shana G
SG
Neumann
Chief Physician's Office, Clalit Health Services, Tel Aviv, Israel.
Doron
D
Comaneshter
Chief Physician's Office, Clalit Health Services, Tel Aviv, Israel.|Siaal Research Center for Family Medicine and Primary Care, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
Arnon D
AD
Cohen
Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel.|Department of Medicine 'B', Zabludowicz Center for Autoimmune Diseases, Sheba Medical Center, Tel-Hashomer, Israel.
Howard
http://orcid.org/0000-0002-5406-7716
H
Amital
D000328:Adult; D000367:Age Factors; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000453:epidemiology*; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006304:Health Status; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000453:epidemiology*; D016017:Odds Ratio; D015995:Prevalence; D012107:Research Design