PURPOSE OF THE STUDY.
To explore the association between sleep duration and sensitization to food allergens and aeroallergens.
There were 1534 rural Chinese adolescent twins aged 12 to 21 years drawn from an ongoing prospective study on precursors of metabolic syndrome in children in a large Chinese twin cohort. Any participant aged 12 to 21 years at a follow-up visit for the main study with complete information on sleep questionnaires and skin-prick-test (SPT) results was included.
Subjects completed standard sleep questionnaires and SPTs to 9 food allergens and 5 aeroallergens. Total sleep time was defined as the interval from bedtime to wake-up time minus sleep latency. Sensitization was defined as having at least 1 positive SPT result. Percentage body fat was calculated, because previous studies have suggested that sleep duration and allergic sensitization are associated with adiposity.
Compared with subjects in the highest tertile of sleep duration, those who slept less were more likely to be sensitized to any food allergen (odds ratio [OR]: 1.9 [95% confidence interval (CI): 1.3–2.7] and 1.4 [95% CI: 1.0–1.9] for the first and second tertiles [trend test Ptrend = 3 × 10−4], respectively). The corresponding ORs for sensitization to any aeroallergen were 1.5 (95% CI: 1.1–2.0) and 1.3 (95% CI: 1.0–1.7) (Ptrend = 8 × 10−3). These associations were independent of percentage body fat. In addition, there was a significant dose-response association between the number of positive SPT results and prevalence of short sleep duration (lowest tertile) (Ptrend = 1 × 10−3).
In this sample of relatively lean rural Chinese adolescents, short sleep duration was associated with increasing risk of sensitization to food allergens and aeroallergens independent of percentage body fat.
A methodologic concern for this study regards the possibility that allergic disease was interrupting sleep, but the authors felt that the allergic sensitization was unlikely to be explained by this confounder because the majority of them were clinically asymptomatic, and the effect persisted even when those with allergic or sleep disorders were excluded from the analysis. This intriguing and previously unreported finding provides further evidence to suggest that immune function is affected by sleep deprivation, which is already known to increase susceptibility to infection. Sleep duration is far more modifiable than many other risk factors for allergic disease and also has other undisputed benefits for overall health, and so this finding has substantial clinical and public health importance. Longitudinal studies are needed to further determine the temporal and causal relationships. In the meantime, get a good night's sleep!
- Copyright © 2011 by the American Academy of Pediatrics