Sleep architecture disturbances in children with bipolar disorder versus attention deficit and hyperactivity disorder: a pilot study

Abstract

Introduction Sleep disturbances on Bipolar Disorder have been widely described and, bidirectionally, some reports point on sleep role on Bipolar Disorder physiopathology. Pediatric Bipolar Disorder (PBD) and Attention Deficit and Hyperactivity Disorder (ADHD) comorbidity is common. Useful biological markers should be found in order to achieve the correct management of both diseases. The aim of this study is to describe sleep architecture on PBD patients and compare to ADHD children. Materials and methods Participants: 4 PBD children (3 males; 4 European Hispanic) and 4 ADHD children (4 males; 3 European Hispanic) aged from 7 to 18 years were recruited from the Child and Adolescent Mental Health Services. Instruments: International Neuropsychiatric Interview for Kids and Adolescents (MINI-Kid) was used for diagnostic purposes. WISC-IV below 70 was an exclusion criterion. Socio-demographic data were recorded. BEARS Algorithm and Sleep Disturbance Scale for Children (SDSC) were applied for sleep disturbances screening. Child Depression Inventory (CDI), Child Mania Rating Scale (CMRS) and Young Mania Rating Scale parent’s version (p-YMRS) were measured the same day of Nocturnal Polysomnography (NPSG) was performed. Hypnogram characteristics were manually scored. Parameters analyzed were Sleep Efficiency, Sleep Time in N1, N2, N3 and REM stages, NoREM and REM Sleep Latencies, duration and number of REM cycles and REM density values. Results All PBD and ADHD participants had at least one current comorbid Axis I disorder. Sleep architecture showed a wide diversity. Significant differences in NPSG values according to PBD or ADHD conditions were not found. Only REM density showed a higher mean value on PBD than on ADHD children. 100% of PBD and 75% of ADHD participants were taking psychotropic medication. Correlations between sleep architecture and current medical treatments could not be established. No correlation between scales for the assessment of mood and sleep variables was found. Conclusion Sleep architecture in PBD and ADHD patients presents heterogeneous patterns. REM density seems to play an important role as biological marker in differential diagnosis of PBD and ADHD. New trials should be applied in order to establish correlations between NPSG variables and PBD or ADHD conditions, psychotropic drugs effects and mood disturbances. Acknowledgement Neurophysiology Department, Hospital del Mar.