title: Asthma and risk of myelodysplastic syndromes: a population-based cohort study.
abstract: Risk factors for the development of myelodysplastic syndromes (MDS) include age, exposure to ionising radiation, and cytotoxic drug treatment. Recently, asthma also has been suggested as a risk factor for MDS.
  
  
  
  We undertook this nationwide population-based cohort study on patients with a first-time hospital-based asthma diagnosis during 2002-2013 and followed them for the development of MDS/chronic myelomonocytic leukaemia (CMML).
  
  
  
  We identified 75 995 patients with incident asthma and no previous MDS/CMML diagnosis. Seventy-eight patients subsequently developed MDS and nine patients developed CMML during 402 892 person-years. The cumulative risks of developing MDS/CMML among asthma patients were 0.02% (95% CI: 0.01-0.04%) and 0.07% (95% CI: 0.05-0.09%) during the first year and the first five years of follow-up, respectively. The standardised incidence ratio of MDS/CMML among asthma patients overall was 1.6 (95% CI: 1.3-2.0) with little variation across subgroups.
  
  
  
  Asthma may be a risk factor for the development of MDS/CMML.
authors.affiliation: Department of Haematology, Odense University Hospital, Odense, Denmark.|Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Henrik
authors.initials: H
authors.lastname: Frederiksen
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Dóra Körmendiné
authors.initials: DK
authors.lastname: Farkas
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Erzsébet
authors.initials: E
authors.lastname: Horváth-Puhó
authors.affiliation: Department of Haematology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Jan M
authors.initials: JM
authors.lastname: Nørgaard
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Mette
authors.initials: M
authors.lastname: Nørgaard
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Henrik T
authors.initials: HT
authors.lastname: Sørensen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001249:Asthma / Q000453:epidemiology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D015477:Leukemia, Myelomonocytic, Chronic / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000453:epidemiology*; D012307:Risk Factors; D055815:Young Adult