Introduction: The most common reasons for obstructive sleep apnea (OSA) in children are enlarged tonsils and adenoids. Previous studies have shown that the size of the adenoids and tonsils are influenced by upper respiratory infections and exposure to allergens. The rate of exposure to bacteria, viruses and allergens fluctuate from season to season. Therefore, it is to be expected that the incidence of OSA will vary according to the season.
Object: To find out whether the prevalence of OSA in children is affected by season
Methods: We retrospectively reviewed polysomnography tests of 296 children, ages 0-12, addressed for suspected OSA. We compared the Obstructive Apnea Hypopnea Index (OAHI) and the rate of positive tests between seasons according to degree of severity.
Results: Mean OAHI was not significantly different between the seasons (winter: 3.0±5.0; spring: 3.0±4.9; summer: 4.0±6.3; fall: 3.4±5.7, p=0.183)
When dividing the Obstructive Apnea Hypopnea Index (OAHI) to levels of severity, no seasonality was found in moderate (winter: 13.8%; spring: 6.7%; summer: 11.7%; fall: 14.1%, p=NS) and severe OSA (winter: 8.8%; spring: 11.2%; summer: 10%; fall: 7.8%, p=NS). There was small increase in the frequency of mild OSA in the summer compared to the other seasons.
Conclusion: There is no clinically significant seasonal effect on OAHI. We therefore speculate that in children with a significant OSA, reevaluation in a different season is not necessary and surgery should not be delayed if indicated.
