Hodgkin lymphoma after autoimmune diseases by age at diagnosis and histological subtype

Increased risk of Hodgkin lymphoma (HL) associated with personal history of several autoimmune diseases (ADs), such as rheumatoid arthritis, systemic lupus erythematosus, sarcoidosis, and immune thrombocytopenic purpura, are known. Whether there are other HL-related ADs and whether the increased risk of HL after ADs holds across sex, age, year of diagnosis, or HL histological subtype is unclear. We systematically analyzed the risk of HL in 878 161 Swedish patients diagnosed with 33 different ADs in 1964-2010. During similar to 10-year follow-up of ADs patients, 371 incident HL cases were diagnosed. Significantly increased overall standardized incidence ratio (SIR) for HL after ADs was 2.0 (95% confidence interval: 1.8-2.2); AD-specific SIRs: autoimmune hemolytic anemia 19.9 (7.2-43.6), sarcoidosis 10.3 (7.8-13.4), systemic lupus erythematosus 8.4 (5.2-12.9), immune thrombocytopenic purpura 7.0 (3.2-13.3), polyarteritis nodosa 6.6 (1.2-19.5), polymyositis/dermatomyositis 6.3 (2.0-14.9), Behcet's disease 5.6 (2.7-10.3), Sjogren's syndrome 5.0 (2.1-9.8), rheumatoid arthritis 3.2 (2.6-3.9), polymyalgia rheumatica 2.2 (1.4-3.5), and psoriasis 1.9 (1.3-2.6). Men with AD had slightly higher risk of HL (2.4, 2.0-2.7) compared with women (1.8, 1.5-2.0). Only 23% of ADs were diagnosed before age 35 years and the overall SIR for HL diagnosis before age 35 [1.4, (1.0-1.8)] was lower than that in older ages [35 a parts per thousand currency sign age < 50: 2.1 (1.6-2.7); age a parts per thousand yen 50: 2.2 (2.0-2.5)], except for sarcoidosis [age < 35: 19.3 (10.5-32.5); 35 a parts per thousand currency sign age < 50: 10.4 (5.7-17.5); age a parts per thousand yen 50: 8.4 (5.6-12.1)]. Risks of all classical HLs significantly increased after ADs: lymphocyte depletion 3.7 (1.5-7.6), lymphocyte-rich 3.7 (2.3-5.9), mixed cellularity 2.4 (1.8-3.2), and nodular sclerosis 1.7 (1.3-2.1). Several, but not all ADs (11/33), had a positive association with all classical histological subtypes of HL. Higher risks of classical HL after polyarteritis nodosa, polymyositis/dermatomyositis, Behcet's disease, Sjogren's syndrome, polymyalgia rheumatica, and psoriasis were novel findings of this study.