Increased chin muscle tone during all sleep stages in children taking selective serotonin reuptake inhibitor antidepressants and in children with narcolepsy type 1

Study Objectives: To assess if selective serotonin reuptake inhibitor (SSRI) antidepressants are able to modify the chin electromyogram (EMG) tone during sleep also in children. Methods: Twenty-three children and adolescents (12 girls, mean age 14.1 years, SD 2.94) under therapy with antidepressant for their mood disorder were consecutively recruited and had a PSG recording. Twenty-one were taking were taking SSRI and treatment duration was 2-12 months. An age- and sex matched group of 33 control children (17 girls, mean age 14.2 years, SD 2.83) and 24 children with narcolepsy type 1 (12 girls, mean age 13.7 years, SD 2.80) were also included. The Atonia Index was then computed for each NREM sleep stage and for REM sleep, also all EMG activations were counted. Results: Atonia Index in all sleep stages was found to be significantly reduced in children with narcolepsy followed by the group taking SSRI antidepressants and the number of EMG activations was also increased in both groups. Fluoxetine, in particular, was found to be significantly associated with reduced Atonia index during NREM sleep stages N1, N2, and N3, and with an increased number of EMG activations/hour during sleep stage N3. Conclusions: Similarly to adults, SSRI antidepressants are able to modify the chin EMG tone in children during REM sleep, as well as during NREM sleep stages. Different pharmacological properties of the different SSRI might explain the differential effect on chin tone during sleep found in this study.