Association of Parasomnia Symptoms with Risk of Childhood Asthma and the Role of Preterm Birth

Abstract

Purpose: To examine whether parasomnia symptoms are associated with increased odds of childhood asthma and wheeze, and the role of preterm birth.

Patients and methods: The Shanghai Children's Allergy Study was cross-sectionally conducted in 31 kindergartens and 17 primary schools in Shanghai, China. After excluding the missing data of gestational week and child's age, this study included a total of 16,487 individuals with a mean age of 7.74 years and 52.4% of males. The association between parasomnia symptoms and wheeze/asthma was assessed by univariate and multivariate analyses. The interaction effects of parasomnias and preterm birth were primarily evaluated by P for multiplicative interaction, and the relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP), and synergy index (SI) were also measured.

Results: Parasomnias, especially rapid eye movement (REM) parasomnia symptoms, were associated with an increased risk of childhood wheeze/asthma, and the interaction between parasomnia and preterm birth exhibited an excess risk of current wheeze (RERI, 1.43; 95% CI, 0.41-2.45) and ever asthma (RERI, 0.75; 95% CI, 0.01-1.50). In the stratification analyses, the combination of parasomnia symptoms and preterm birth had higher odds of wheeze/asthma. And the odds of current wheeze (OR, 4.55; 95% CI, 1.69-12.25; p=0.003) and ever asthma (OR, 6.17; 95% CI, 2.36-16.11; p<0.001) were much higher in cumulative parasomnia symptoms plus very preterm birth. And sensitive analyses were further conducted in populations without sleep disordered breathing (SDB), and an allergen test subgroup, yielding similar results.

Conclusion: Parasomnia symptoms are associated with increased odds of childhood wheeze/asthma, and the odds were even higher in premature population. The findings suggest that parasomnia symptoms, as a developmental sleep disorder, are supposed to be closely watched among children who have asthma or are at risk for asthma, and that preterm children deserve more attention.

Keywords: premature; respiratory allergies; sleep; sleep disorders.

Figure 1

Flow chart of this study. For this study, a total of 16,963 students were recruited from 36 kindergartens and 17 primary schools. 296 children were ruled out because they were not between the ages of 3 and 12, and 161 were ruled out owing to missing data on gestational week, leaving 16,487 children in the final analysis. In the analysis process, 6955 children without any allergic diseases (asthma, wheeze, allergic rhinitis, eczema, food allergy, and drug allergy) were regarded as the control group, and 2086 being screened for current wheeze and 2338 being screened for ever asthma. In the allergen test subgroup, 1257 children who had a positive response to both current wheeze/ever asthma and the allergen test were included, while 5546 children who did not have any of the stated allergic diseases and did not take the allergen test were regarded as reference group.

Figure 2

Age specific prevalence of current wheeze/ever asthma and single parasomnia symptoms.

Figure 3

Forest plot for allergen test subgroup. Model adjusted for child age, overweight/obesity, gender, mother’s educational level, father’s educational level, family income, family structure, family allergic history, family sleep disorder history, maternal age at delivery, maternal pre-pregnancy overweight, maternal smoking, maternal drinking, negative life event, cesarean delivery, preterm birth, low birthweight, multiple pregnancy, breastfeeding, passive smoking, pet keeping during first year of life.