Childhood Maternal Warmth, Social Safety Schemas, and Adolescent Mental and Physical Health.

Importance: Although early maternal warmth strongly predicts adolescent health, questions remain about the biopsychosocial mechanisms underlying this association. Objective: To understand how maternal warmth at 3 years of age shapes adolescent social safety schemas at 14 years of age and physical and mental health at 17 years of age. Design, Setting, and Participants: The Millennium Cohort Study tracks approximately 19 200 children born from late 2000 to early 2002 in the UK. Participants were assessed from ages 3 to 17 years. Exposure: Low maternal warmth (eg, lack of praise, negative tone of voice when speaking to the child) and maternal harshness (eg, using physical restraint, grabbing the child) were independently coded during a home visit (age 3 years). Main Outcomes and Measures: Social safety (age 14 years) was measured by children's responses to 3 items (eg, "I have family and friends who help me feel safe, secure and happy"). Physical health was self-reported on a scale ranging from 1 (excellent) to 5 (poor) (age 17 years). Psychological distress (age 17 years) was assessed using the 6-item Kessler Psychological Distress Scale. Psychiatric problems (age 17 years) was a latent variable composed of self-disclosed clinical diagnosis of depression/anxiety, self-harm, and suicidal behaviors. Results: The present sample included 8540 youths (52% female; 3.0% Black or Black British, 2.8% Indian, 6.7% Pakistani and Bangladeshi, 2.8% Mixed, 83% White, and 1.6% other). Data were analyzed from March 2024 to September 2024 using structural equation modeling. In models controlling for sex, ethnicity, income, neighborhood disadvantage, maternal mental health, and early cognitive ability, the paths from childhood maternal warmth (but not harshness) to social safety schemas at 14 years of age (b = 0.03; P < .001) and physical health at 17 years of age (b = 0.05; P = .02) were significant, suggesting that early maternal warmth enhances subsequent perceived social safety and physical health. Additionally, the paths from negative social safety schemas at 14 years of age to poorer physical health (b = 0.50; P < .001), psychological distress (b = 5.37; P < .001), and psychiatric problems (b = 0.21; P < .001) at 17 years of age were significant, suggesting that greater perceived social safety prospectively predicts better health. Social safety at 14 years of age mediated 20% to 100% of the effect of early maternal warmth on physical health, psychological distress, and psychiatric problems at 17 years of age (b = 0.01-0.15; P < .001 for all). Conclusions and Relevance: These results show that early-life maternal warmth affected adolescent health by influencing perceptions of social safety. Improving parent-child relationships and enhancing youths' perceptions of social safety may thus improve adolescent health.