0717 Restless Sleep Associated with Low Ferritin Levels: A Retrospective Study in a Pediatric Sleep Center

Introduction A significant challenge in diagnosing Restless Leg Syndrome in children is the child’s inability to verbally describe their symptoms. In our pediatric sleep clinic, it has been recognized that restless sleep is a routine element of the clinical history for children presenting with a wide range of sleep disturbances. A literature review showed substantial literature about the prevalence and characteristics of restless sleep in children, but there is little showing the effect of ferrous sulfate on symptoms in children. A deficiency of brain iron stores results in a reduction of dopamine production and the clinical expression of RLS. Brain iron stores cannot be directly quantified for clinical purposes but can be evaluated indirectly by measuring serum ferritin. In the clinical framework of RLS, it is generally accepted that a serum ferritin < 50 ng/ml is too low, despite still being considered within normal range for most reference labs and replacing this with oral elemental iron should be considered the first line treatment. Methods A retrospective chart review was performed of patients seen in the Sleep Clinic at Arkansas Children's Hospital from 2018-2021 who had a report of restless sleep and a serum ferritin drawn. If the ferritin was lower than 50 ng/ml, they were treated with ferrous sulfate for a minimum of three months. After three months, patient’s symptoms were reevaluated, and ferritin levels drawn to determine if improvement had occurred. Results In total, 1,000 charts were reviewed. Ferritin levels < 50 ng/ml were found in 75.2% of the patients. Of the patients with a serum ferritin >50 ng/ml after treatment with ferrous sulfate, 62.8% reported an improvement in restless sleep and 37.2% reported no change in symptoms. Conclusion Low ferritin levels were found in a large number of our pediatric patients with restless sleep. The administration of ferrous sulfate in the patient population showed an improvement in symptoms of restless sleep in a majority of patients. Support (if any)