Primary myelofibrosis: Older age and high JAK2V617F allele burden are associated with elevated plasma high-sensitivity C-reactive protein levels and a phenotype of progressive disease

•We have measured plasma levels of hs-CRP in 526 subjects with PMF.•38% of subjects with PMF had elevated hs-CRP.•Age≥52years and JAK2V617F mutation with≥50% allele burden were independently associated with elevated hs-CRP.•Older age and high allele burden JAK2V617F mutation were also associated with a phenotype of progressive disease.•We interpreted our finding as reflecting an intrinsic inflammatory pathway promoted by older age and high allele burden JAK2V617F.