Effects of cardiac radiation on sleep and psychological distress in adult survivors of pediatric Hodgkin lymphoma without breathing sleep disorders.
Authors: Navarrete Miguel , Mulrooney Daniel A. , Roop Joshua , Guthrie Stephanie , Ogg Susan , Ness Kirsten K. , Hudson Melissa M. , Mandrell Belinda Neal , Krull Kevin R. 
Published: June 2024

10068 Background: Adult survivors of childhood Hodgkin lymphoma (HL) are at higher risk for excessive sleepiness, fatigue, and other morbidities that affect long-term quality of life (QoL). The relationship between radiation dose to the heart delivered during treatment and self-reported sleep quality, fatigue, QoL, and psychological distress in survivors of HL has not been explored. This study examines clusters of cardiac dosimetry and sleep quality and associated symptoms of insomnia, fatigue, QoL, and psychological distress in a subset of adult survivors of pediatric HL without breathing sleep disorders. Methods: Survivors completed standardized surveys of sleep quality (Pittsburg Sleep Quality Index, PSQI), insomnia (Insomnia Severity Index), fatigue (FACIT-F), QoL (SF36 short survey), and psychological distress (BS18). Two consecutive nights of in-home polysomnography were completed with at least 4 hours of recorded sleep in one night. Analyses were conducted on 95 survivors (mean[SD] age=36[7.2] years, 55 female) who demonstrated at least average sleep efficiency (>85%) and demonstrated no evidence of sleep apnea (Apnea-Hypopnea Index <5, or AHI >5 and <15 with no daytime sleepiness as defined by the American Society of Sleep Medicine). Radiation dose to the heart was estimated using dose reconstruction methods for therapeutic radiation exposure developed by the MD Anderson Cancer Center. Radiation/Sleep clusters were found using a silhouette analysis and K-means algorithm. Linear regression associations between clusters and outcomes were adjusted by age and body mass index. Statistical analyses were computed in the statsmodels toolbox for Python3. Results: Sleep and radiation were not correlated (ρ=0.03, p=0.67). Considering good sleep as PSQI<5, three main Radiation/Sleep clusters were found indicating a low-radiation/middling-sleep group (22%; RT = 251[250.7] cGy, PSQI = 7[2.7]), a high- radiation/better-sleep group (46%; RT = 2012[406.8] cGy, PSQI = 4[1.5]), and a high- radiation/worst-sleep group (32%; RT = 2072[472.3] cGy, PSQI = 11[2.5]). Survivors in high-radiation/worst-sleep group demonstrated worse fatigue ( β=-12.3, p=0.001) and insomnia ( β=9.52, p<0.001). This group was associated with poor Mental Health ( β=-2.1, p<0.001) but not Physical Health QoL ( β=-0.4, p=0.154). This latter group also indicated more psychological distress (depression β=11.6, p=0.001, somatization β=11.8, p<0.001), but not anxiety ( β=4.6, p=0.241). Conclusions: Our results highlight the burden of symptoms associated with higher radiation dosimetry in the heart including poor sleep quality, insomnia, fatigue, and increased psychological distress. Understanding the mechanisms of sleep quality and fatigue in HL survivors is warranted as some survivors demonstrate poor sleep quality and fatigue due to factors other than clinical sleep disorders.