Clinical and prognostic significance of concomitant autoimmune disease in patients with myelofibrosis.

There is growing interest in the association between autoimmune diseases (AID) and myeloproliferative neoplasms (MPN), yet the specific clinical and prognostic implications of AID in myelofibrosis (MF) remain insufficiently characterized. A retrospective analysis was conducted in patients diagnosed with primary MF (PMF) or secondary MF (SMF). Concomitant AID diagnoses were identified through medical record review and included only cases with documented clinical diagnosis. A total of 135 patients with MF were analyzed, including 90 (66.7%) with PMF and 45 (33.3%) with SMF. At diagnosis, 31 AID diagnoses were recorded in 29 patients (21.5%), of which 54.8% were organ-specific and 45.2% systemic. AID was more frequent in female patients (p = 0.005). At a median follow-up of 37.3 months, 3-year overall survival (OS) was 78%, with inferior OS in patients with systemic AID (61%; p = 0.028) compared to those without AID (79%) or with organ-specific AID (88%). In multivariable analysis, systemic AID (HR 2.16, p = 0.043), anemia (HR 1.79, p = 0.041), age (HR 1.08, p < 0.001), and JAK-inhibitor therapy (HR 0.57, p = 0.023) independently predicted mortality. Severe infections and thrombotic events were more frequent in AID patients (26% vs 9.3%, p = 0.0082), with significance retained for infections alone (p = 0.016). The presence of AID did not affect the rate of leukemic transformation. Systemic AID identifies a subset of MF patients with worse survival and increased susceptibility to infections, supporting intensified surveillance and tailored management strategies in this population.