Role of Symptom Burden in Disability Leave Among Patients with Myeloproliferative Neoplasms (MPNs): Findings from the Living with MPN Patient Survey

Background: Patients with myeloproliferative neoplasms (MPNs), including myelofibrosis (MF), polycythemia vera (PV), and essential thrombocythemia (ET), experience a high symptom burden that compromises daily functioning and quality of life. Objective: To describe the prevalence and nature of medical disability leave (MDL) among patients with MPNs, and its relationship with MPN symptoms. Methods: An online survey of adult patients (aged 18-70 years) with MF, PV, or ET in the United States was conducted between April and November of 2016. Data collected included patient demographics, MPN diagnosis, MDL due to MPNs since diagnosis (short-term or long-term, date of leave and return), history of thrombotic events, MPN-related symptoms (using the MPN Symptom Assessment Form [MPN-SAF]), and physical, mental, and social functional status in the prior 7 days. MPN total symptom score (TSS) was calculated as the sum of the scores for the 10 symptoms included in the MPN-SAF. Symptoms and functional status were compared between patients who took MDL and patients with no employment change using the t-test and chi-square test, respectively. Results: Among the total of 904 patients that participated in the survey, 592 patients were employed at the time of MPN diagnosis; 147 (24.8%) subsequently took MDL because of their MPN (MF, 66/174 [37.9%]; PV, 55/248 [22.2%]; ET, 26/170 [15.3%]; Table 1 ), 293 (49.5%) reported no change in employment because of their MPN, and the remaining152 patients had other employment change (e.g., early retirement, hour reduction). Among patients who took MDL, the mean age at diagnosis was 46 years, 66% were female, the mean duration of disease was 6.6 years, and 31% had a history of thrombotic event (TE). Among patients with no employment change, the mean age at diagnosis was 48 years, 71% were female, the mean duration of disease was 5.9 years, and 15.4% had a history of TEs. The mean time from MPN diagnosis to the first MDL was 2.3 years. Overall, 29.9% of patients took ≥2 MDLs, 48.3% took long-term leave, and by the time of the survey 62.6% did not return to work after their latest MDL. Among those who returned to work, the mean length of leave was 4.3 months; 46.3% of those who took MDL received social security benefits. A significantly higher symptom burden was reported among those who had gone on MDL compared with those with no employment change (mean MPN-TSS: 42.9 vs 20.1; P Table 2 ). Fatigue or tiredness, bone pain, and day or night sweats were the most severe symptoms among patients who took MDL. A higher proportion of patients who took MDL vs patients with no employment change had functional impairments, such as difficulty with strenuous physical activities (91.2% vs 64.8%), remembering things (90.5% vs 60.8%), and sleeping (84.4% vs 58.7%; all P Conclusions: Approximately one quarter of employed patients took MDL because of their MPN, nearly one half of whom took long-term leave. Patients who took MDL had significantly higher symptom burden vs those with no employment change. Most patients who went on MDL did not return to the workforce. Effectively managing MPN diseases and associated symptoms may reduce disability leave among those patients. Disclosures Yu: Incyte Corporation: Employment, Equity Ownership. Paranagama: Incyte Corporation: Employment, Equity Ownership. Parasuraman: Incyte Corporation: Employment, Equity Ownership. Mesa: Galena: Consultancy; Gilead: Research Funding; Incyte Corporation: Research Funding; Novartis: Consultancy; Ariad: Consultancy; Celgene: Research Funding; Promedior: Research Funding; CTI: Research Funding.