Health-Related Quality of Life, Disease Impacts, and Health Equity Concerns in Adults with Sickle Cell Disease with Recurrent Vaso-Occlusive Crises: Preliminary Results from a Global Longitudinal Survey

Introduction: Sickle cell disease (SCD) is characterized by vaso-occlusive crises (VOCs) and a progressive clinical course, often leading to end-organ damage and accelerated mortality. Individuals with SCD with recurrent VOCs experience disruptions to daily life due to recurrent pain crises and debilitating chronic pain and fatigue, which affect their ability to work and substantially impair their health-related quality of life (HRQoL). Nonetheless, HRQoL and disease impacts in this population are not well quantified. Here, we report preliminary findings from a prospective longitudinal study evaluating the HRQoL, work productivity impacts, and health equity concerns among adult participants with SCD with recurrent VOCs.

Methods: A mixed-methods study was conducted to quantify the symptoms, HRQoL, and work impacts of adults with SCD with recurrent VOCs. The study consisted of qualitative interviews and an online longitudinal survey administered at 3 timepoints (time 0, 3 months, and 6 months) in the US, the UK, France, Germany, and Italy. The survey included multiple patient-reported outcomes measures (PROMs): the Functional Assessment of Cancer Therapy-Bone Marrow Transplant (FACT-BMT), composed of the Functional Assessment of Cancer Therapy-General (FACT-G) and a BMT subscale (BMTS); EuroQol 5-Dimension 5-Level (EQ-5D-5L); 11-point pain Numerical Rating Scale (NRS); Adult Sickle Cell Quality of Life Measurement Information System (ASCQ-Me); and Work Productivity and Activity Impairment (WPAI) questionnaire. Symptoms, comorbidities, treatment experiences, out-of-pocket costs, time spent managing SCD, and participants' health equity concerns were also collected and evaluated. Survey invitations were sent to patient communities via patient advocacy groups. Participants were required to meet the eligibility criteria and provide consent. Eligibility criteria included experiencing ≥2 VOCs/year, in each of the 2 years before study enrollment, that required interaction with a healthcare provider and administration of pain medication or a red blood cell transfusion. Descriptive analyses were conducted for participant characteristics and PROMs based on survey findings at time 0. Data are reported as mean (standard deviation [SD]), unless noted.

Results: The survey was completed by 142 participants with SCD (aged ≥18 years) living in the US (n=85) and the UK, Germany, France, and Italy (n=57) at time 0. Overall, 71.8% were female (n=102), the mean age was 35.5 years (10.4), and 15.5% (n=22) had full-time employment (≥32 hours/week). In the prior 12 months, participants reported a mean of 5.9 (4.8) VOCs that required interaction with a healthcare provider and pain medication and spent a mean of 14.6 (24.7) days in the hospital. In the past month, 62.0% (n=88) were taking hydroxyurea to manage their condition.

The mean FACT-G total score was 62.2 (18.5) (0-108 scale; 108=best HRQoL), which is lower than in the US general population (80.1 [18.1]). The largest impacts were observed on the physical (-23.9% relative difference) and emotional well-being domains (-16.3% relative difference) vs the US general population. Participants reported a mean EQ-5D-5L visual analog scale score of 58.7 (19.4), with 89.9% reporting pain/discomfort, 74.1% anxiety/depression, 71.2% mobility impairment, and 46.8% self-care impairment.

Significant HRQoL impairments were also observed on the ASCQ-Me vs the SCD reference population, with the largest differences observed on the pain (41.5 [9.0]), stiffness (41.1 [8.2]), and emotional (43.5 [7.6]) impact domains. Among those employed (n=47), 42.0% (27.8%) reported work impairment (presenteeism), 24.7% (27.1%) absenteeism, and 53.4% (27.5%) work productivity loss on the WPAI. Among all respondents (n=137), the mean activity impairment was 52.6% (26.0%). On healthcare equity concerns, 68.3% (n=97) felt that they had been treated unfairly while seeking care, with most attributing the unfair treatment to their race/ethnic background (67.0%) and/or requesting more pain medicine (64.9%). Results were consistent in a subset of 18-to-35-year-old participants.

Conclusions: Adults with SCD with recurrent VOCs currently receiving treatment experience significant HRQoL impact, impaired work productivity, and health equity concerns, indicating substantial humanistic burden and unmet needs in this patient population.

Drahos:Vertex Pharmaceuticals Incorporated: Current Employment, Current equity holder in private company, Current holder of stock options in a privately-held company. Boateng-Kuffour:Vertex Pharmaceuticals Incorporated: Current Employment, Current equity holder in private company, Current holder of stock options in a privately-held company. Calvert:Takeda: Consultancy; European Commission and EFPIA: Research Funding; Janssen: Research Funding; University of Maastricht: Honoraria; Merck: Consultancy; PROTEUS Consortium: Membership on an entity's Board of Directors or advisory committees, Other: Paid via consultancy fee (from Genetech and PCORI); UCB Pharma: Research Funding; NIHR: Research Funding; Research England: Research Funding; Daiichi Sankyo: Consultancy; Glaukos: Consultancy; Genentech: Consultancy; GSK: Consultancy, Other: Family member has stock GSK, Research Funding; Macmillan Cancer Support: Research Funding; Innovate UK: Research Funding; PCORI: Consultancy; UK Research and Innovation: Research Funding; Gilead: Research Funding; Brain Tumor Charity: Research Funding; Health Data Research UK: Research Funding; Vertex Pharmaceuticals Incorporated: Consultancy; Aparito Ltd: Consultancy; CIS Oncology: Consultancy. Valentine:Vertex Pharmaceuticals Incorporated: Consultancy; Atlas Clarity Consulting Firm: Consultancy; IVI: Membership on an entity's Board of Directors or advisory committees; PCORI: Membership on an entity's Board of Directors or advisory committees. Mason:Vertex Pharmaceuticals Incorporated: Consultancy. Pakbaz:Novartis: Consultancy, Honoraria, Research Funding; Global Therapeutics: Consultancy, Honoraria, Research Funding, Speakers Bureau; Amgen: Consultancy, Research Funding; Vertex Inc: Consultancy, Honoraria; Sobi: Consultancy, Honoraria, Speakers Bureau; Terumo: Honoraria; Dova: Consultancy, Honoraria, Speakers Bureau; Sanofi: Consultancy, Honoraria; Guide point: Consultancy; Cayenne Wellness Center and Child Fundation: Honoraria, Other: CME course director for Cayenne Wellness Center and Child foundation annual educational symposium. Cayenne Wellness Center and Child foundation annual educational symposium, planning committee member.. Oran:Vertex Pharmaceuticals Incorporated: Current Employment, Current equity holder in private company, Current holder of stock options in a privately-held company, Other: As an employee in Vertex Pharmaceuticals, my expenses regarding meetings are paid by Vertex Pharmaceuticals.. Iqbal:Vertex Pharmaceuticals (Europe) Limited: Current Employment, Current equity holder in private company, Current holder of stock options in a privately-held company. Shah:Agios: Membership on an entity's Board of Directors or advisory committees; Silence Therapeutics plc: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis Pharma AG: Honoraria, Other: Support for attending meetings and/or travel.; Bristol Myers Squibb: Consultancy, Membership on an entity's Board of Directors or advisory committees; IQVIA: Other: Adjudication committee contract (Novartis Pharma AG); Biologix FZ co.: Honoraria; Chiesi Ltd: Honoraria; Vertex Pharmaceuticals Incorporated: Current Employment, Current equity holder in private company, Current holder of stock options in a privately-held company, Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Honoraria; Uk forum on haemoglobin disorders: Membership on an entity's Board of Directors or advisory committees; bluebird bio Inc: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Support for attending meetings and/or travel. Li:Vertex Pharmaceuticals Incorporated: Current Employment, Current equity holder in private company, Current holder of stock options in a privately-held company. Martin:QC Medica LLP: Current Employment; Vertex Pharmaceuticals Incorporated: Consultancy, Research Funding.