Impact of the COVID-19 Pandemic on Early Child Cognitive Development: Initial Findings in a Longitudinal Observational Study of Child Health

ObjectiveTo characterize cognitive function in young children under 3 years of age over the past decade, and test whether children exhibit different cognitive development profiles through the COVID-19 pandemic. Study DesignNeurocognitive data (Mullen Scales of Early Learning, MSEL) were drawn from 700 healthy and neurotypically developing children between 2011 to 2021 without reported positive tests or clinical diagnosis of SARS-CoV-2 infection. We compared MSEL composite measures (general cognition, verbal, and non-verbal development) to test if those measured during 2020 and 2021 differed significantly from historical 2011-2019 values. We also compared MSEL values in a sub-cohort comprising infants 0-16 months of age born during the pandemic vs. infants born prior. In all analyses, we also included measures of socioeconomic status, birth outcome history, and maternal stress. ResultsA significant decrease in mean population MSEL measures was observed in 2021 compared to historical references. Infants born during the pandemic exhibited significantly reduced verbal, non-verbal, and overall cognitive performance compared to children born pre-pandemic. Maternal stress was not found to be associated with observed declines but a higher socioeconomic status was found to be protective. ConclusionsResults reveal a striking decline in cognitive performance since the onset of the COVID-19 pandemic with infants born since mid-2020 showing an average decrease of 27-37 points. Further work is merited to understand the underlying causative factors.