Sleep Characterization of Adolescent and Young Adult Patients with Sickle Cell Disease Using the Pittsburgh Sleep Quality Index
Authors: Gloston Gabrielle F , Thomas S. Justin , Maxwell Sarah , Lebensburger Jeffrey D. , Kanter Julie , Schlenz Alyssa M 
Published: November 2021

Abstract
Introduction: Poor sleep quality is common across the lifespan in patients with sickle cell disease (SCD) and has been associated with pain, mood disruption, and fatigue. The Pittsburgh Sleep Quality Index (PSQI) examines sleep quality in both pediatric and adult patients with chronic health conditions, including in adolescents and young adults (AYAs) with SCD. The AYA period is particularly salient for patients with SCD given the potential onset of chronic pain during this developmental period and increased risk for complications during transition. Previous studies have relied on the PSQI total score rather than examining specific domains of sleep quality. In addition, prior studies have mostly focused on either pediatric or adult patients rather than examining AYAs as a group. This study examined specific PSQI sleep domains to identify characteristics that may be impaired in AYAs with SCD. This approach may allow for a multidimensional understanding of sleep in AYAs with SCD and may identify specific targets for intervention.
Methods : We performed a retrospective chart review of AYA patients with SCD who completed the PSQI as part of a clinical pilot program. Patients included all types of SCD between 13-25 years. We recorded the PSQI and demographic and medical characteristics (age, sex, SCD type, CBC, and SCD treatments). Descriptive data from PSQI subdomains (sleep duration, latency, efficiency, needing medication to sleep, subjective sleep quality, and mid-sleep time [mid-point between sleep onset and offset]) were examined for adolescents (ages 13 to 18) and young adults (ages 19 to 25) to identify sleep characteristics (table 1). A mean PSQI score &gt; 5 is categorized as having poor sleep quality. Chi-square and Fisher's exact test were used to compare age differences in characteristics for adolescents versus young adults.
Results : Eighty-nine AYAs with SCD (mean age: 18.9±3.5 years; 51 female, 38 male) completed the PSQI. Patients were evenly distributed across adolescent (n = 46) and young adult groups (n = 43). SCD genotypes included: HbSS (n = 58), HbSC (n = 15), HbSb + (n = 9), HbSb 0 (n = 3), HbSO-Arab (n = 2), and unknown (n = 2). Adolescents and young adults did not significantly differ for sex, SCD genotype, CBC, or current therapies (all p .3). Average total PSQI scores for adolescents and young adults were 6.26 and 9.02, respectively. Most adolescents (52%) and young adults (84%) reported poor sleep quality (total PSQI score &gt; 5). Thirty nine percent of adolescents rated their sleep duration as less than 7 hours compared to over half of young adults (56%). Many adolescents (59%) and young adults (44%) endorsed a mild to moderate amount of sleep disturbance, with many young adults (47%) also reporting a high amount of sleep disturbance. A large percentage of young adults (68%) and some adolescents (37%) reported prolonged sleep latency and subsequent daytime dysfunction due to sleepiness [adolescents (63.0%) and young adults (77%)]. Sleep efficiency was inadequate in 59% of adolescent and 72% of young adults. More young adults (35%) than adolescents (7%) reported needing medication to sleep. Despite noted sleep deficiencies, subjective sleep quality was frequently rated as "very good" or "fairly good" by adolescents (91%) and young adults (72%). Midsleep time serves as a proxy for chronotype (morning or night person). Mean midsleep time was 4.75 and 4.95 in young adult and adolescent participants, indicating a late chronotype. Among sleep domains, sleep latency, subjective sleep quality, needing medication to sleep, and overall sleep quality were worse among young adults versus adolescents (p = .002 to .012).
Conclusion : Adolescents and young adults with SCD had poor sleep quality across multiple PSQI domains. Young adults also reported poorer sleep quality in certain domains versus adolescents, suggesting that some sleep characteristics may worsen during transition. Results highlight the need to be vigilant for sleep problems and the need for sleep education for AYAs with SCD. Future studies focused on the efficacy of behavioral sleep medicine interventions that target sleep deficiencies in AYAs with SCD are also important. This study was limited by using a convenience sample rather than a random sample of patients from the clinic. This study is also cross-sectional and longitudinal efforts are needed to better understand the evolution of sleep difficulties during the AYA developmental period.
Figure 1 Figure 1.

Disclosures
Lebensburger: Bio Products Laboratory: Consultancy; Novartis: Consultancy. Kanter: Fulcrum Therapeutics, Inc.: Consultancy; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Forma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Agios: Honoraria, Membership on an entity's Board of Directors or advisory committees; Beam: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees; Graphite Bio: Consultancy; GuidePoint Global: Honoraria; Fulcrum Tx: Consultancy.