Overnight Respiratory Support for Prevention of Morbidity in Sickle Cell Disease (POMS 2a) - Parent and Child Preferences

PURPOSE: Obstructive sleep apnea and nocturnal hypoxemia are common in children with sickle cell disease (SCD) and some degree of improvement has been reported following adenotonsillectomy(Finch et al., 2013). NOT and continuous positive airways pressure (CPAP) have shown some benefits in children and adolescent patients(Hargrave, 2003). While NOT and CPAP are offered to children with or without co-morbidities, there are concerns about acceptability and safety(Makani et al., 2009). The data on patient preference is limited in childhood and more so for those with SCD. To achieve optimal adherence to therapy in SCD, Auto-Adjusting Positive Airways Pressure (APAP), where airway pressure is delivered only when obstruction occurs, may be a more acceptable option than CPAP(Marshall et al., 2009). Therefore prior to designing Phase II and III trials that are adequately powered, this study sought to: i) identify parent/caregiver and child treatment preference; ii) assess whether parent/caregiver or child should manage the electronic pain diary; iii) assess any treatment effect on Health Related Quality of Life (HRQOL) in children; and iv) explore the relationship of treatment adherence to: a) experience of pain, and b) overall clinical benefit from the intervention.

HYPOTHESES:

1. Treatment adherence of children or adults with would be directly related a) HRQOL quantitative measures, and b) improvement in symptoms reported through semi-structured interviews of patients;

2. Children >8 years would be able to record their experience of pain in an appropriate electronic pain diary;

3. Treatment adherence would be predictive of effect on pain frequency.

METHOD: We utilised mixed-methods to explore the primary endpoint of patient experience of treatment intervention, and the secondary endpoint of pain, in a sample of 11 children (aged >8 years) with homozygous SCD. The statistician was blinded to order of intervention. Two interventions NOT and APAP were conducted for one week each in randomized order, with a washout week between interventions. Qualitative data was obtained through in-depth interviews with children and their parents/caregivers conducted by a research psychologist using content method of analysis; quantitative measures were explored employing the Pediatric Quality of Life Inventory^TM (PedsQL)(Panepinto et al., 2013) including the sickle module. All analyses were preliminary, exploratory and mainly descriptive. The secondary endpoint of pain was captured utilizing a pain rating scale and symptom assessment on smart technology via an iPad(Jacob et al., 2012). Other secondary outcomes included adverse events, daytime oxygen saturation, and lung function.. All variables were reported for three time points: baseline, post-intervention 1 and post-intervention 2.

RESULTS: Analysis of interviews between children and parents/caregivers revealed similarities in expectations prior to treatment, and variations in post-study perception of treatment. Parents/caregivers and children emphasised impact on other family members, practical concerns and challenges as objective criteria for treatment preference, while children additionally emphasized night time positive/negative sensory experiences: e.g. airflow, dreams, breathing, sound, as influences for treatment preference. Belief that treatment is beneficial only for children with breathing difficulties emerged as an influence on both expectation and perception of positive benefits. In 7 children for whom APAP adherence data were available, pain was noted after 3 nights with a median adherence of 5.23 (range 4.0-6.1) hours and was not noted after 38 nights with a median adherence of 8.03 (range 3.21-10.19) hours (p=0.2). For 4 children with pain recorded on 2, 2, 2 and 4 days in the pre-treatment week, 3 recorded no pain on APAP and the child with 4 days pre-treatment recorded 2 days on APAP.

CONCLUSIONS: These data reveal some variation in approaches toward treatment preferences between parents/caregivers and children, and supports an inclusive approach to facilitate appropriate treatment choice. Adherence data are not available for oxygen but there is some evidence for reduction in pain in relation to APAP adherence. This trial will contribute to understanding in participant feasibility and acceptability for therapeutic intervention. Research results will be used to inform design of the Phase II and III trials.