Abstracts

Rationale: There has been little research conducted on the relationship between Down syndrome, infantile spasms and heart disease. It is estimated that 5-13% of individuals with Down syndrome will develop seizures with the most common type being infantile spasms (Arya, Epileptic Disord., 2011 Mar; 13(1):1-7). Congenital heart disease, another common comorbidity, is reported to occur in 40-60% of patients with Down syndrome with complete atrioventricular septal defect being the most common defect (Anaclerio, Ital Heart J. 2004; 5(8):624-628 & Formigari, Ann Thorac Surg. 2004; 78(2): 666-672). Other frequently occurring lesions include atrial and ventricular septal defects and tetralogy of Fallot (Fudge, Pediatrics 2010 Aug; 126(2):315-22). In our previous study comparing treatment outcomes of patients initially treated with ACTH or vigabatrin versus anticonvulsants, we found a high incidence of cardiac disease (70.4%). Another prior investigation focusing on infantile spasms in Down syndrome also noted this high percentage in 9 out of 11 children (Lujie, Coll. Antropol. 2011 Jan; 35 Suppl 1:213-8). Examining this prevalence of infantile spasms in children with Down syndrome and heart disease may lead to earlier diagnosis and greater positive outcomes. Methods: Retrospective chart review data was collected from 35 patients treated at a single institution from April 2005 until December 2013 as part of a planned 10-year longitudinal study. All patients met inclusion criteria of infantile spasms onset prior to three years of age and diagnosis of Down syndrome. Results: Of the 27 patients with Down syndrome and infantile spasms that have been analyzed so far, the following rates of comorbidities were found: cardiac disease (70.4%), thyroid abnormalities (25.9%), prematurity defined as ≤ 37 weeks (22.2%), and stroke (3.7%). Although all children with Down syndrome have a higher incidence of these comorbidities, these rates are significantly higher in this study population than what is reported in the literature (Bull, Pediatrics 2011; 128(2):393-406). Of the 20 patients with cardiac disease the most common finding was patent ductus ateriosis (50%, n=10), followed by atrial septal defect (40%, n=8), ventricular septal defect (35%, n=7), patent foramen ovale along with a second defect (30%, n=6), PFO only (10%, n=2), and aberrant subclavian artery (5%, n=1). Note that a number of patients had a combination of cardiac findings. From this list five children had surgical repairs at last follow up. Conclusions: Overall, the findings of this study indicate an increased risk of infantile spasms in children who have Down syndrome and cardiac findings. Raising awareness of this possible affiliation is critical to providing early observation, recognition, and treatment of infantile spasms. This may include informing providers of the potential affiliation, as well as educating families regarding the presenting features of infantile spasms. While this investigation has one of the largest samples of children with Down syndrome and infantile spams in the literature, continued study of this occurrence is needed.