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Prevalence and risk factors for disrupted circadian rhythmicity in children with optic nerve hypoplasia

S A Rivkees1, C Fink, M Nelson

  • 1Department of Pediatrics, Yale Child Health Research Center, 464 Congress Avenue, New Haven CT 06520, USA. scott.rivkees@yale.edu

The British Journal of Ophthalmology
|June 26, 2010
PubMed

Insights

Abnormal sleep-wake cycles affect 30% of children with optic nerve hypoplasia (ONH). Severe vision impairment, abnormal pupillary response, developmental delay, and hormonal deficiencies predict these sleep disturbances in ONH patients.

Area of Science:

  • Pediatric Neurology
  • Sleep Medicine
  • Endocrinology

Background:

  • Optic nerve hypoplasia (ONH) is associated with visual impairment, hypopituitarism, and developmental delay.
  • Sleep-wake abnormalities have been anecdotally reported in children with ONH.

Purpose of the Study:

  • To determine the incidence and characteristics of sleep-wake abnormalities in children with ONH.
  • To identify potential predictors of these sleep disturbances.

Main Methods:

  • Actigraphy was used to assess rest-activity patterns in 23 children with ONH.
  • Participants also underwent formal assessments of pituitary function, vision, pupillary response, neurocognition, and brain MRI.

Main Results:

  • Abnormal rest-activity rhythmicity was observed in 32% of the children (n=6).
  • Abnormalities included fragmented sleep, free-running cycles, and arrhythmicity.
  • Children with abnormal rhythmicity showed higher rates of severe visual impairment (100%), abnormal pupillary response (85%), cognitive impairment (100%), and multiple hormonal deficiencies (66%).

Conclusions:

  • Approximately 30% of children with ONH exhibit abnormal rest-activity rhythmicity.
  • Severe vision impairment, abnormal pupillary responsiveness, developmental delay, and multiple hormonal deficiencies are significant predictors of abnormal sleep-wake patterns in this population.
Abstract

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