Parallel Increase in Childhood Anorexia Nervosa and Early Puberty During the COVID-19 Pandemic.

Objective: During the COVID-19 pandemic, an increase in anorexia nervosa (AN), specifically childhood AN, as well as in central precocious puberty (CPP) and early-onset puberty (EOP), was reported. The aim of this study was to explore whether there was a population-level association between increases in both disorders and to discuss possible underlying causes.

Method: Data were retrieved from the largest health insurance institution in Germany comprising approximately 3.5 million children between 0 and 14 years for the years 2019-2023. All female cases with a diagnosis of AN/atypical AN and those with CPP/EOP according to ICD-10 were included. To investigate possible specificity of associations, we also examined associations with depressive disorders (DD) and anxiety disorders (AD).

Results: Decreasing and increasing numbers of cases with EOP, CPP, and childhood AN/atypical AN showed a similar pattern during the COVID-19 pandemic. The number of diagnosed cases of AN/atypical AN combined with either CPP (Spearman's ρ = 0.45; p = 0.02), EOP (Spearman's ρ = 0.60; p = 0.003), or combined CPP/EOP (Spearman's ρ = 0.53; p = 0.008) in this time span was highly and significantly correlated. Associations with CPP/EOP were generally stronger for AN/atypical AN than for DD (Spearman's ρ = 0.45; p = 0.02) or AD (Spearman's ρ = 0.29; p = 0.11).

Discussion: The highly increasing prevalence of childhood AN, EOP, and CCP may reflect pandemic-associated stress and lifestyle changes and/or their effects on reproductive functioning. Pre- and peripubertal girls seem to be especially vulnerable to these environmental stressors and might react with important physical and mental impairments.