A standardized clinical evaluation and questionnaire was, beginning in 1985, applied to infants referred for an apparent life-threatening event (ALTE). All children who underwent this "core evaluation protocol" during a 10-year period were reviewed. Documentation of clinical complaints, symptoms and signs of sleep-disordered breathing, sleep/wake evaluation, systematic evaluation of the face and naso-oro-pharynx, nocturnal polygraphic recording, and systematic follow-up was conducted. A total of 346 infants had complete data sets, with a smaller group of 46 age-matched healthy infants as controls. A scorer blind to the clinical data analyzed the polygraphic investigation and divided the 346 referred into two groups. Group A, 42.6% of the population, included infants with no abnormal findings based on nocturnal polygraphic recording. These infants were no different from controls at initial evaluation and during follow-up. Group B, 57.4% of the population, included infants who had obstructive breathing during sleep which became more obvious over time. Two-thirds of these infants not only had clinical symptoms of sleep-disordered breathing but also had mild facial dysmorphia that could be seen clearly at 6 months of age.
Conclusion: A subgroup of infants with apparent life-threatening events present an indication of a sleep-disordered breathing syndrome which is associated with a mild dysmorphia. This mild facial dysmorphia needs to be recognized early to distinguish these infants from other infants with apparent life-threatening events and to initiate appropriate treatment.