Background In adults, increased sympathetic and decreased parasympathetic nervous system activity are associated with a less favorable metabolic profile. Whether this is already determined at early age is unknown. Therefore, we aimed to assess the association between autonomic nervous system activation and metabolic profile and its components in children at age of 5–6 years. Methods Cross-sectional data from an apparently healthy population (within the ABCD study) were collected at age 5–6 years in 1540 children. Heart rate (HR), respiratory sinus arrhythmia (RSA; parasympathetic activity) and pre-ejection period (PEP; sympathetic activity) were assessed during rest. Metabolic components were waist-height ratio (WHtR), systolic blood pressure (SBP), fasting triglycerides, glucose and HDL-cholesterol. Individual components, as well as a cumulative metabolic score, were analyzed. Results In analysis adjusted for child’s physical activity, sleep, anxiety score and other potential confounders, increased HR and decreased RSA were associated with higher WHtR (P< 0.01), higher SBP (p<0.001) and a higher cumulative metabolic score (HR: p < 0.001; RSA: p < 0.01). Lower PEP was only associated with higher SBP (p <0.05). Of all children, 5.6% had 3 or more (out of 5) adverse metabolic components; only higher HR was associated with this risk (per 10 bpm increase: OR = 1.56; p < 0.001). Conclusions This study shows that decreased parasympathetic activity is associated with central adiposity and higher SBP, indicative of increased metabolic risk, already at age 5–6 years.

Depressive symptoms are common in the postpartum period and can affect mother–infant interaction. To better understand the role of depressive symptoms in the mother–infant interchange, this study examined whether maternal depressive symptoms are associated with self-reported, physiological, and facial expressive responses to infant crying and laughing sounds. A nonclinical sample was used, consisting of 101 mothers (Age M = 30.88 years, 33% scored 7 or higher on the Edinburgh Postnatal Depression Scale) with a young child. Mothers were exposed to standard infant crying and laughing sounds. Affect, perception of crying and laughing, intended caregiving responses, skin conductance level reactivity, and facial expressive responses to infant crying and laughing were measured. Higher levels of depressive symptoms were associated with more self-reported negative affect in general and a more negative perception of infant crying. Depressive symptoms were not associated with intended caregiving responses and physiological responses to infant crying. Infant laughing increased self-reported positive affect and happy facial expressions in mothers with all levels of depressive symptoms. Higher levels of depressive symptoms were associated with higher sad facial expressivity in general. Depressive symptoms were not related to positive perception of infant laughing, intended caregiving responses, and physiological responses to infant laughing. The findings suggest that mothers who score high on depressive symptoms send subtle facial cues showing sadness, which may overshadow happy facial expressions during infant laughing and may affect mother–infant interaction. (PsycInfo Database Record (c) 2023 APA, all rights reserved)