# Sleep and Trajectories of Respiratory and Allergic Symptoms Between 1 and 5.5 Years of Age in the Elfe Birth Cohort

## TL;DR

Poor sleep in 1-year-old children is linked to more respiratory and allergic symptoms by age 5.5, suggesting early sleep issues may predict later health problems.

## Contribution

This study identifies early sleep patterns as predictors of later respiratory and allergic health trajectories in children.

## Key findings

- Poor sleep at age 1 is associated with higher odds of persistent respiratory and allergic symptoms by age 5.5.
- Four distinct respiratory and allergic symptom trajectories were identified between ages 1 and 5.5.
- The association between early sleep disturbances and health outcomes was stronger in children without early wheezing.

## Abstract

Sleep troubles and respiratory and allergic health issues are associated in children, but the timeline of their association is overlooked. This study investigates the associations between sleep patterns at age 1 and respiratory and allergic multi‐trajectories (RespA‐MTG) between ages 1 and 5.5, and the associations between these multi‐trajectories and sleep at age 5.5 in the ELFE birth cohort. Sleep clusters at ages 1 and 5.5 (based on nocturnal and diurnal sleep duration, sleep onset difficulties, and night awakenings) and RespA‐MTG between ages 1 and 5.5 (based on wheezing, asthma medication, eczema, allergic conjunctivitis) were identified using data‐driven methods. Associations between sleep clusters and RespA‐MTG were assessed using multinomial regressions adjusted for confounders in 9577 children. Two sleep clusters were identified at ages 1 and 5.5: good sleepers (79.9% at age 1, 83.1% at 5.5) and poor sleepers (20.1% and 16.9%, respectively). Four RespA‐MTG were identified: pauci‐symptomatic (44.4%), persistent non‐respiratory allergic symptoms (23.1%), transient early respiratory symptoms (25.2%), and persistent respiratory and allergic symptoms (7.3%). Poor sleep at age 1 was associated with higher odds of transient early respiratory symptoms (Odds Ratio [95% Confidence Interval], 1.14 [0.99–1.31]) and persistent respiratory and allergic symptoms (1.29 [1.05–1.59]). Results were reinforced in children without wheezing at 2 months. A borderline association was observed between persistent respiratory and allergic symptoms and sleep at 5.5 in good sleepers at 1 year (1.22 [0.98–1.50]). In conclusion, sleep disturbances at age 1 are associated with later poorer respiratory and allergic health, suggesting early sleep troubles may predict these health concerns.