Obstructive sleep apnea syndrome due to adenotonsillar hypertrophy in infants.

Objective: Adenotonsillar hypertrophy (ATH) is the leading cause for obstructive sleep apnea syndrome (OSAS) in children. The peak age for adenoid and tonsillar hypertrophy and related OSAS is 3-6 years. It has been suggested that OSAS due to ATH is extremely rare in infants. The purpose of the present study was to delineate OSAS due to ATH in infants.

Methods: Twenty-nine consecutive infants <18 months of age who underwent polysomnography (PSG) and were diagnosed with OSAS due to ATH were studied. A pediatric sleep questionnaire was completed by parents of all infants. Information regarding demographic variables, referring physician specialty, assessment of infant's development and recurrence of symptoms post treatment was collected. Pre and post surgery body weight and developmental assessment by parents were evaluated.

Results: The mean age of adenotonsillectomy was 12.3+/-3.9 months with the mean duration of symptoms ranging 6.2+/-3.0 months. 24% of the infants were born preterm. Snoring was the most common finding and appeared in all infants. Other symptoms were sleep apnea (72%), frequent movements during sleep (69%), mouth breathing (62%) and recurrent awakenings (38%). During the preoperative period, mean body weight decreased from the 67th+/-25 percentile to the 42nd+/-32 percentile (P<0.00001). 14/29 (48%) of the infants dropped two or more major percentiles before treatment. A significant weight gain to the 59th+/-31 percentile was observed post surgery (P<0.0001). 5/29 (17%) infants were considered by their parents as having a developmental delay preoperatively, which resolved in 3/5 (60%) post treatment. Clinical symptoms resolved or improved significantly after surgery. Recurrence of symptoms was documented in 6/23 (26%) of infants.

Conclusions: Infantile OSAS due to hypertrophic adenoids and tonsils does occur in infants. Unique characteristics for this age group include: male predominance, high incidence of preterm infants, failure to gain weight and high recurrence rate after surgery. Otolaryngologists and pediatricians should be aware to the existence of the "early OSAS" in small infants.