Incidence of and risk factors for myelodysplastic syndromes in patients with rheumatologic diseases.

OBJECTIVE: We investigated the incidence rate and risk factors of myelodysplastic syndromes (MDS) in patients with rheumatologic disease. METHODS: We conducted a retrospective cohort study of patients who were diagnosed with rheumatologic diseases at a tertiary-care hospital between May 2009 and July 2022 and identified the patients who were subsequently diagnosed with MDS. Each patient with MDS was matched with five age- and sex-matched controls chosen from the cohort of patients with each specific rheumatologic disease. RESULTS: During a total follow-up of 55 841 person-years (PY), MDS occurred in 64 patients, yielding an incidence rate of 1.15/1000 PY (median age, 57.0 [IQR, 41.0-69.0]; median duration to MDS diagnosis, 6.5 years [IQR, 3.0-9.0]). In an age-matched analysis, systemic lupus erythematosus (SLE) was a significant risk factor for MDS (adjusted hazard ratio, 2.61 [CI, 1.19-36.06], P= 0.01). Refractory cytopenia with multilineage dysplasia was the most common phenotype of MDS (35.9%), and more than half of the patients had karyotypes with favorable prognoses (54.7%). Compared with matched controls, rheumatoid arthritis, SLE, and ankylosing spondylitis patients with MDS had lower levels of haemoglobin at the time of diagnosis of rheumatologic disease. Furthermore, the MDS patients with SLE and Behcet's disease had higher levels of glucocorticoid use in terms of frequency of use or mean dose than the control patients. CONCLUSION: SLE is a significant risk factor for MDS among patients with rheumatologic diseases. A lower haemoglobin level at the time of diagnosis of rheumatologic disease was associated with the future development of MDS.