Differences between aquagenic and non-aquagenic pruritus in myeloproliferative neoplasms: An observational study of 500 patients.

BACKGROUND

Pruritus is a frequent symptom experienced by patients with myeloproliferative neoplasms (MPN). Aquagenic pruritus (AP) is the most common type. The Myeloproliferative Neoplasm-Symptom Assessment Form Total Symptom Score (MPN-SAF TSS) self-report questionnaires were distributed to MPN patients before consultations.

OBJECTIVES

The aim of this study was to assess clinical incidence (phenotypical evolution and response to treatment) of pruritus, especially AP, in MPN patients during their follow-ups.

PATIENTS AND METHODS

We collected 1444 questionnaires from 504 patients [54.4% essential thrombocythaemia (ET) patients, 37.7% polycythaemia vera (PV) patients, and 7.9% primary myelofibrosis (PMF) patients].

RESULTS

Pruritus was reported by 49.8% of the patients, including 44.6% of AP patients, regardless of type of MPN or driver mutations. Patients suffering from pruritus were more symptomatic and had a higher rate of evolution into myelofibrosis/acute myeloid leukaemia (19.5% vs. 9.1%, OR = 2.42 [1.39; 4.32], p = 0.0009) than MPN patients without pruritus. Patients with AP had the highest pruritus intensity values (p = 0.008) and a higher rate of evolution (25.9% vs. 14.4%, p = 0.025, OR = 2.07) than patients with non-AP. Disappearance of pruritus was observed in only 16.7% of AP cases, compared to 31.7% of cases with other types of pruritus (p < 0.0001). Ruxolitinib and hydroxyurea were the most effective drugs to reduce AP intensity.

CONCLUSIONS

In this study, we demonstrate the global incidence of pruritus across all MPN. Pruritus, especially AP, which is a major constitutional symptom observed in MPN, should be assessed in all MPN patients due to higher symptom burden and higher risk of evolution.