Myelofibrosis (MF), polycythemia vera (PV), and essential thrombocythemia (ET) represent three of the most common Philadelphia chromosome negative myeloproliferative neoplasms (MPN). Individuals with these disorders suffer from excessive debilitating fatigue compared to age-matched controls. Although cytokine deregulation and impaired hematopoiesis contributes to the intrinsic causes of MPN-related fatigue, there may be contributory effects of underlying mood. To date few studies have prospectively evaluated the role of mood disorders on fatigue among this population.
A 70-item internet-based survey was developed by MPN investigators and patient/advocates and hosted by the Mayo Clinic Survey Research Center. The survey was promoted online via multiple MPN-related webpages including the MPN Forum, MPN Net, MPN Research Foundation, and MPN Voice during February/March of 2014. Surveyed data included disease demographics such as splenomegaly, thrombosis, hemorrhage transfusions, medications, and phlebotomies. The MPN-SAF (including the MPN 10), and Brief Fatigue Inventory were used to assess disease burden (Blood. 2011 14;118(2):401-8). Mental health was assessed using the Profile of Mood States (POMS-short form (J Nerv Ment Dis. 1979;167(10):612-4)), Patient Health Questionaire (PHQ-2 (Ann Fam Med. 2010. 8(4): 348–353)) and Mental Health Inventory (MHI-5 (J Consult Clin Psychol. 1983. 51;730-742)).
Demographics: Overall 1788 MPN patients participated in the survey. Of these, 1676 consented to participate and provided additional data (answered at least 10 questions). Of these, 555 (33%) patients had ET, 651 (39.0%) have PV, and 417 (25.0%) have MF. Respondents were 68% female with a mean age of 59. Overall brief fatigue inventory score had a mean of 4.4 (range 0-10). MPN-10 score average was 28.4 (range 0-83).
Psychological Comorbidities: Mental health assessments were obtained among participants. Mean PHQ-2 score was 1.6 (SD = 1.6, range 0-6.0). Twenty three percent of respondents scored greater than or equal to three on the PHQ-2 indicating a high probability of depression (mean = 1.6 (SD = 1.6, range 0-6)). Additionally, average MHI-5 score was 21.8 (SD = 4.9), with scores less than 60 likely representing a mental disorder with minimal misclassification rate (BMC Psychiatry. 2008. 19;8:10). Mean POMS-B score was 76.9 (SD=19.9, mean subscale scores: tension-anxiety 15.1, vigor-activity 6.0, fatigue-inertia 10.0, depression-dejection 15.5, confusion-bewilderment 14.3, anger-hostility 15.7). Patients frequently endorsed having being seen for or diagnosed with depression (32.0%), anxiety (29.5%), stress (26.2%), and grief (15.0%). Of participants, 22.2% had received active treatment of a mood disorder in the past 6 months. When queried on treatments of mood disorders, respondents often had received medication treatments (81.4%), counseling/therapy (40.3%), and group therapy (6.0%).
Correlations: Many significant correlations were observed between MPN-SAF items and PHQ, MHI-5, and POMS-B (Table 1). When evaluating likelihood of depressive symptoms (as assessed by a PHQ), survey items including older age (p= 0.0006) and lower educational attainment (p=0.0001) were noted to have significant association with depressive symptoms . Higher BFI, MPN-10, and individual MPN-SAF scores were significantly associated with a higher likelihood of depressive symptoms (p<0.0001).
Overall many MPN patients reported having had coexisting mood disorders. The frequency of mood disturbance is likely greater than that in the general population (e.g., 11% of individuals in the primary care population have PHQ-2 greater than or equal to 3 (Ann Fam Med. 2010; 8(4): 348–353) and average control population POMS-B total mood disturbance score = 34.1 (BioPsychoSocial Medicine 2011, 5:6)). The causality of relationship between mood disorders and MPN-related fatigue severity is not entirely clear, fatigue could contribute to depressive symptoms, depression could cause fatigue, or it can be bidirectional. Thus mood disorders may represent a primary or secondary process in the disease course. Evaluation of MPN-related fatigue should be multifactorial, and should take into consideration underlying mood disorders as part of a comprehensive assessment and subsequent treatment regimen.
Harrison:Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau; Sanofi: Consultancy, Honoraria; CTI: Consultancy, Honoraria; Gilead: Honoraria; SBio: Consultancy; Shire: Speakers Bureau. Mesa:Incyte: Research Funding; Novartis: Consultancy; Gilead: Research Funding; Genentech: Research Funding; Promedior: Research Funding; Ns Pharma: Research Funding; Celgene: Research Funding; Lilly: Research Funding; Cti: Research Funding.
Asterisk with author names denotes non-ASH members.