Personal history of autoimmune disease and other medical conditions and risk of myelodysplastic syndromes

Background: Autoimmune diseases and hematopoietic malignancies are known to cluster within individuals, suggesting intertwined etiologies. A limited number of studies have evaluated pre-existing medical conditions as risk factors for myelodysplastic syndromes (MDS). We evaluated associations between autoimmune disease and other medical conditions and risk of MDS. Methods: Cases were identified through the Minnesota Cancer Reporting System. Controls were identified through the Minnesota State driver's license/identification card list. History of autoimmune disease and other medical conditions was based on self-report; proxy interviews were not conducted. Unconditional logistic regression was used to calculate adjusted odds ratios (aORs) and 95% confidence intervals (CI). Results: We included 395 cases and 694 controls. Cases were significantly more likely to report a diagnosis of any autoimmune disease when compared with controls (aOR=1.41, 95% CI: 1.05–1.89) after adjustment for age, sex, education, NSAID use, exposure to benzene and body mass index. When we evaluated specific autoimmune conditions, a statistically significant association was observed for hypothyroidism (aOR=2.16, 95% CI: 1.39–3.34) and odds ratios were elevated for inflammatory bowel disease (aOR=1.75) and systemic lupus erythematosus (SLE; aOR=3.65), although these associations did not reach statistical significance. Presence of an autoimmune condition did not impact overall survival (p = 0.91). Conclusion: Our results validate previous findings of an association between autoimmune disease and MDS. Further studies are required to determine whether this association is due to shared etiology, treatment for autoimmune diseases, or altered immune surveillance or bone marrow damage caused by the autoimmune condition.