0918 SLEEP AND NEUROENDOCRINE PROFILES IN 3- AND 9-MONTH OLD INFANTS WITH A FAMILY HISTORY OF AUTISM

Abstract

Introduction: Circadian abnormalities have been associated with Autism Spectrum Disorder (ASD) based on separate reports of sleep and hormone irregularities. Limited information is known about the etiology and emergence of those co-occurring conditions. Since ASD is only diagnosed reliably after 2-3 years of age, we are examining the developmental trajectory of sleep and hormone rhythms in infants at greater risk for ASD because they have an older sibling with the disorder. Method(s): Sleep and hormones are being rigorously characterized at 3, 9 and 12 months in infants from families with and without a history of ASD. Data include: The Children's Sleep Habits Questionnaire (modified); 7 days of actigraphy and sleep diary; and salivary melatonin and cortisol across one day (at 0800, 0900, 1000, 1800 and 2100). Result(s): To date, there are no significant differences in total sleep time between low- and high-risk infants at either 3 or 9 months. Bedtimes do not differ between groups at 3-months but are relatively earlier in low- versus high-risk infants at 9 months (p<0.05). High-risk 9-month old infants were also more likely to fall asleep in a bed other than their own (p<0.01). Preliminary cosinor analyses yield significant 24-hour rhythms at 3 months for melatonin in 4/10 low-risk and 1/3 high-risk infants, and for cortisol in 1/9 low-risk and 0/2 high-risk infants. Conclusion(s): Thus far, there are no group differences in infant sleep at 3 months but possible deviations at 9 months of age. The emergence of circadian rhythms is already observed in hormone profiles at 3-months in some infants; however, increased sample sizes are necessary. Better understanding of sleep and circadian dysfunction often co-occurring with ASD may help guide treatment strategies and minimize the negative impact of these disturbances on both the children and their families.