Relationships between extent of social contacts, sleep duration and amount of eating in infants during confinement

ABSTRACT

Introduction: The surge of COVID-19 infections in 2020 led European countries to enforce confinement to reduce direct contact within populations. Isolation can have negative health consequences, and a fly model shows that chronic isolation reduces sleep duration and increases food intake. Similarly, social isolation in adults relates to reduced sleep quality. Yet, whether this model transfers to developing humans is unknown. Our study aimed to explore if social distancing during confinement relates to sleep and food intake in infants. We hypothesized that infants experiencing a higher extent of distancing have shorter sleep and increased food intake. Method(s) An online questionnaire (in Spanish, German, English, French, Italian) distributed in April/May 2020 quantified parentreported sleep duration (Brief Infant Sleep Questionnaire) and the infant's direct contact with friends and extended family. A 5 point Likert scale captured whether meal size increased, decreased or remained unchanged since the beginning of the confinement. We collected data on 350 infants <=3 years old (18.2 +/- 10.0 months, 170 girls). Result(s) Sleep duration did not differ between infants who had direct contact with their friends (n = 22) compared to those without direct contact (n = 312) when controlling for age (p = 0.44, multiple linear regression). There was also no difference in sleep duration between infants with direct contact with their family (n = 81) compared to those without direct contact (n = 266) when controlling for age (p = .90, multiple linear regression). Similarly, there was no group difference in the confinement-induced change of meal size dependent on contact with friends (p = .39, Chi-squared test), or with family (p = .91, Chi-squared test). Discussion(s) Thus, the extent of distancing as part of the COVID-19 confinement in 2020 did not correlate with infants' sleep duration and their quantity of meals, which indicates that isolation has a different effect in developing humans than in adults or flies. As infants depend on close contact with their parents, effects of isolation on sleep and eating might only appear beyond infancy.