Allergic sensitization and objective measures of sleep in urban school-aged children with asthma.

Background: Allergic sensitization is associated with increased child asthma morbidity and decreased pulmonary function. Nocturnal symptoms and/or awakenings typically are measured by self-report from diary data, whereas objective assessments of sleep in child asthma studies are lacking.

Objective: To investigate the association between increased allergic sensitization (number of positive allergy test results measured by skin prick test or specific immunoglobulin E) and sleep outcomes (sleep efficiency, sleep duration, and mean number of awakenings measured by actigraphy) in urban schoolchildren with persistent asthma.

Methods: One hundred ninety-six children with persistent asthma (7-9 years old) attending public school in 1 of 4 large urban school districts completed allergy testing during a study clinic visit. Forced expiratory volume in 1 second was monitored at home using a handheld spirometer. Sleep outcomes were measured with a wrist Actiwatch during a 1-month period in the fall and winter seasons.

Results: Number of positive allergy test results significantly predicted mean sleep efficiency (P = .02), such that children with more positive test results experienced less efficient sleep. Number of positive allergy test results significantly predicted mean number of night awakenings (P = .05), such that children with more positive allergy test results experienced more night awakenings. Variability in forced expiratory volume in 1 second was a significant moderator in the association between number of positive allergy test results and variability in sleep efficiency (P = .04). Racial and ethnic differences in allergic sensitization and sleep outcomes were found between African Americans and Latinos.

Conclusion: More positive allergy test results were associated with poorer sleep outcomes measured objectively in this sample of urban children. Implications for environmental control interventions and asthma treatments in different racial and ethnic groups are discussed.