Polycythemia Vera Symptoms Not Linked to Blood Count Control, Study Says

A study of patients with polycythemia vera (PV) showed that the severity of individual symptoms was not affected by blood count control.

The only exception was for pruritus and night sweats.

About half of patients with PV experience substantial symptom burdens, which may hurt quality of life and get in the way of daily activities. Symptoms may worsen as the disease progresses and can persist despite control of blood counts, which suggests some discordance between laboratory values and symptom burden. The researchers said an assessment of the relationship between blood count control and symptoms had not been published previously.

The data for this study came from the ongoing Prospective Observational Study of Patients with Polycythemia Vera in US Clinical Practices (REVEAL), a multicenter, noninterventional, nonrandomized prospective observational US study. The aim of REVEAL is to describe disease burden, clinical management, patient-reported outcomes, and healthcare resource use among patients with PV; the current study examines the effect of blood count control on symptom burden as measured by the 10-item Myeloproliferative Neoplasm Self-Assessment Form Total Symptom Score (MPN-SAF TSS). The MPN-SAF TSS asks about worst fatigue, early satiety, abdominal discomfort, inactivity, problems with concentration, night sweats, pruritus, bone pain, fever, and weight loss.

Scoring ranged from 0 (none) to 10 (worst imaginable). Scores 7 and above were considered “severe,” scores of 4 to 6 were considered moderate, and scores of 1 to 3 were considered mild. Symptom severity was compared between those who had blood count control versus those who did not.

A total of 2510 patients were enrolled over an approximate 2-year period (July 2014 to August 2016), with 2307 patients having completed the MPN-SAF TSS at enrollment as required. Of these, 1813 patients (72.2%) could be evaluated, since they had a complete blood count within 30 days before completion of the at-enrollment MPN-SAF TSS and were evaluable.

Among evaluable patients, the median age was 67 years (range, 22-95 years), 985 (54.3%) were male, and 1642 (90.6%) were white. The median age at diagnosis was 61 years; the median time from PV diagnosis to enrollment was 4.1 years. A large proportion (57.0%) of patients had a PV duration of less than 5 years; 18.8% of patients had a PV duration of 10 years.

At the time of enrollment, most patients (n = 1714; 94.5%) were being managed with cytoreductive therapy; 1581 patients (87.2%) were managed with phlebotomy, hydroxyurea, or a combination.

Approximately one-quarter of evaluable patients (n = 468; 25.8%) had complete hematologic remission (CHR) at the time of enrollment; 1614 patients (89.0%) had at least 1 controlled blood count, and 1122 patients (61.9%) had at least 2 controlled blood counts.

Mean MPN-SAF TSSs were similar across patients in different blood count control groups. Fatigue was the most frequently reported symptom. The severity of individual symptoms, except those of pruritus and night sweats, was not affected by CHR or the number of blood counts that were controlled.

The authors said regular monitoring of symptom burden should be considered when assessing disease control.

Reference

Grunwald MR, Burke JM, Kuter DJ, et al. Symptom burden and blood counts in patients with polycythemia vera in the United States: An analysis from the REVEAL study [published online June 13, 2019]. Clin Lymphoma Myeloma Leuk. doi: 10.1016/j.clml.2019.06.001.