Disease Characteristics of Minority Patient Populations with Polycythemia Vera: An Analysis from the Reveal Study

Abstract

Introduction: Polycythemia vera (PV) is associated with increased blood cell counts, risk of thrombosis, and symptoms including fatigue and pruritus. Few studies have examined the presence or absence of racial/ethnic disparities among patients with PV. The objective of this analysis is to describe differences in disease characteristics, diagnosis, treatment, and quality of life (QOL) among Caucasian and non-Caucasian patients with PV in the United States enrolled in the prospective, observational REVEAL study.Methods: The ongoing REVEAL study (ClinicalTrials.gov ID, NCT02252159) is a prospective, multicenter, observational study of adult patients with PV in the United States. Patients were observed during a 36-month period, during which clinical data were collected from usual care visits. This analysis compared demographics, disease and clinical characteristics, disease management, comorbidities, and QOL between Caucasian and non-Caucasian patients with PV at enrollment. QOL was measured by the European Organisation for Research and Treatment of Cancer Questionnaire C30 (EORTC QLQ-C30) and Myeloproliferative Neoplasm Symptom Assessment Form Total Symptom Score (MPN-SAF TSS). Results are summarized with descriptive statistics.Results: Of the 2,510 patients enrolled in REVEAL, 2,237 were Caucasian (89.1%); 199 (7.9%) were non-Caucasian, comprised of African American (5.7%), Asian (1.5%), Native American Indian (0.2%), Pacific Islander (0.1%), and other patients (0.4%); no information was provided regarding race or ethnicity for 74 patients (2.9%). Baseline disease characteristics were similar for Caucasian and non-Caucasian groups with respect to gender and disease duration. There were no differences in method of diagnosis, laboratory values, or overall history of thrombosis between groups (Figure 1A). Mean age was higher among Caucasian patients compared to non-Caucasian patients (66.6 vs 63.8 years, respectively). The proportion of patients from rural areas was higher among Caucasian vs non-Caucasian patients (28.8% vs 12.6%); similarly, the proportion of patients from urban areas was lower among Caucasian vs non-Caucasian patients (23.1% vs 46.7%). The proportion of patients with some college or higher level of education was higher among Caucasian vs non-Caucasian patients (64.1% vs 50.3%). A higher proportion of Caucasian vs non-Caucasian patients were retired (52.0% vs 43.2%); a higher proportion of non-Caucasian patients reported being unable to work or were disabled (3.8% vs 10.1%).More Caucasian patients had high-risk disease (78.0%) compared with non-Caucasian patients (71.4%), and patients with high-risk disease were managed similarly between groups. However, Caucasian patients with low-risk disease received more phlebotomies (56.6%) than non-Caucasian patients with low-risk disease (40.4%), and over twice as many non-Caucasian patients received hydroxyurea (38.6%) than Caucasian patients (15.6%) (Figure 1B). MPN-SAF TSSs were higher for non-Caucasian patients compared with Caucasian patients, suggesting a worse symptom burden. Similarly, non-Caucasian patients reported lower functional and symptom outcomes on the EORTC QLQ-C30, including a disparity in financial difficulties, compared to Caucasian patients (Figure 1C).Conclusions:This analysis evaluated a cohort of racial/ethnic minority patients with PV treated in the United States. As in other cancer-related trials, there is a risk that racial and ethnic minorities may be underrepresented in REVEAL. With this limitation in mind, in this analysis, differences were not observed among Caucasian and non-Caucasian patients with respect to method of diagnosis, duration of disease, thrombosis rates, or management of high-risk disease. Non-Caucasian patients demonstrated higher rates of low-risk disease and cytoreductive therapy for low-risk disease yet had worse symptom burden, lower functional scores, and greater disability. This study underscores the importance of symptom assessment and ancillary resource availability for patients with PV DisclosuresAltomare:Bayer: Consultancy; Genentech: Consultancy; Ipsen: Other: Advisory Board Member; Celgene: Other: Advisory Board Member; Incyte: Consultancy; Novartis: Consultancy; Amgen: Consultancy. Colucci:Incyte: Employment, Equity Ownership. Parasuraman:Incyte: Employment, Equity Ownership. Paranagama:Incyte: Employment, Equity Ownership.