Impact of Sickle Cell Disease Symptoms on Patients' Daily Lives: Interim Results from the International Sickle Cell World Assessment Survey (SWAY)

Background: Sickle cell disease (SCD) is a multi-system disease affecting millions of people. The disease is characterized by vaso-occlusive crises (VOCs), resulting in acute and chronic pain, end-organ damage and life-threatening complications. The symptoms experienced by patients, caused largely by multi-cellular adhesion leading to vaso-occlusion and vasculopathy, significantly affect their quality of life (QoL) and ability to work/study. Understanding the effect of SCD on patients' daily lives can inform management of the disease and improve patients' QoL.

Aims: To assess the impact of SCD on patients' daily lives, including physical symptoms, emotional wellbeing and economic burden, based on the worldwide SWAY survey.

Methods: SWAY is an ongoing multi-country, cross-sectional survey of SCD patients, caregivers and treating physicians. Data are collected using self-completed or proxy surveys and categories include demographics, symptoms and impact of disease (physical, emotional and financial) and need for a caregiver. Where relevant, questions include a 7-point severity scale for each statement, with a score of 5 to 7 indicating 'high severity/impact'. Patient enrollment is via treating physicians and patient association groups. The enrollment target is approximately 2000 patients.

Results: To date, 1513 SCD patients (48% male, mean age 24.1 years, 63% HbSS and 30% SC disease) have been surveyed from countries across the world, including the USA (365), UK (299), Nigeria (264), Ghana (255), Brazil (160) and Germany (91). The most commonly experienced symptoms of SCD were bone aches (63%), difficulty concentrating (49%), difficulty gaining weight (49%) and joint stiffness (41%). For these symptoms, 67%, 53%, 70% and 59% of patients rated them as 'high severity' on the 7-point scale, respectively. Background pain was present on an average of 2.9 days per week (standard deviation [SD]=2.2). Commonly experienced complications of SCD include fever (65%), joint issues (55%) and infections (55%). Patients reported a total of 7829 VOCs, with a mean of 5.2 VOCs per patient (SD=5.07) in the 12 months before survey completion; 38% of these VOCs resulted in overnight hospitalization, 24% were managed at home, 19% were treated in the emergency room and 19% of patients sought medical assistance in the community.

A high impact on emotional wellbeing was reported by 61% of patients. The highest impact was caused by frustration with symptoms (60%), worry about disease worsening (59%) and worry about family/friends/children who care for them (54%). Only 42% of patients have received professional emotional support (eg psychiatrist, psychologist, counseling), but 67% reported a desire to receive this support.

A high impact on household daily activities (eg food preparation, housework, childcare) and on family or social life was reported by 39% and 43% of patients, respectively, with 34% stating a high impact in terms of sexual desire/activity and 35% a high impact on relationships with spouse/partner. Physical activity was also affected in patients with SCD, with 60% reporting they avoid intense physical activity and 30% avoiding even mild physical activity, most commonly because of concerns about pain, exhaustion and dehydration (58%, 57% and 50%, respectively).

Of the patients surveyed, 32% were employed, 8% not working but seeking employment, 6% not working and not seeking employment, 36% students, 1% retired, 13% on disability pay and 1% long-term sick leave. Employed patients reported SCD had a high impact on their ability to work, with 57% reducing their hours and 47% considering leaving their job. An average of 6.3 hours missed from work was reported in the 7 days prior to survey completion due to SCD. Half of patients believe that their income would be higher if they did not have SCD, 60% reported often missing school in the past and 52% felt that their disease has had a negative impact on their academic achievements.

Conclusions: The acute and chronic symptoms associated with SCD have a substantial impact on patients' daily lives, including emotional and physical wellbeing, relationships and school/work. In addition, the acute symptoms associated with VOCs occur several times a year, resulting in frequent hospitalizations. Improved management of SCD would enhance patients' quality of life both at home and at school/work, likely leading to improved emotional wellbeing and a positive economic effect.