Hip and Knee Osteoarthritis in Patients with Chronic Myeloproliferative Neoplasms: A Cross-Sectional Study

Osteoarthritis (OA) is a progressive degenerative disease with an inflammatory background. Chronic myeloproliferative neoplasms (MPN) are clonal hematopoietic disorders characterized by chronic inflammation and a tendency for connective tissue remodeling.

This study aimed to investigate the prevalence and associated risk factors of symptomatic OA (sOA) in MPN patients.

A total of 100 consecutive MPN (39 essential-thrombocythemia, 34 polycythemia-vera, 27 myelofibrosis) patients treated in two community hematologic centers were cross-sectionally evaluated. Patients were required to have both symptoms attributable to hip and/or knee OA and radiographic confirmation to be considered as having sOA.

The prevalence of hip and/or knee sOA was significantly higher among MPN patients than the previously reported prevalence in the general population of similar age (61% vs. 22%, p < 0.001). Hip sOA was present in 50%, knee sOA in 51% and sOA of both localizations in 41% of patients. A high proportion of MPN patients had radiographic signs of hip OA (94%) and knee OA (98%) in the presence of attributable symptoms. Among the other factors, sOA was univariately associated with the presence of JAK2 mutation, myelofibrosis phenotype, older age, higher body weight, and higher MPN-SAF score (p < 0.050 for all analyses). In the multivariate analysis, older age (odds ratio = 1.19, 95% confidence interval-CI 1.06-1.33) and higher body weight (OR = 1.15, 95% CI 1.06-1.25) were recognized as independent risk factors for sOA. On the other hand, cytoreductive treatment was a protective factor for sOA (OR = 0.07, 95% CI 0.006-0.86).

The prevalence of sOA in MPN patients was higher than that in the general population and seems to correlate with older age, increased myeloproliferation and a higher inflammatory state. Whether cytoreductive treatment may postpone OA development in MPN patients warrants additional confirmation.