Study: Childhood maltreatment continues to impact mental, physical health in adulthood

Childhood maltreatment can have a long-term impact on an individual's likelihood of poor physical health and traumatic events, according to a new study. 

Individuals who have experienced childhood maltreatment, such as emotional, physical, and sexual abuse, or emotional and physical neglect, are more likely to develop mental illness later in life, but it is unclear why this risk persists decades after the maltreatment occurred.

In a study published in the Proceedings of the National Academy of Sciences, scientists from the University of Cambridge and Leiden University discovered that childhood maltreatment continues to affect adult brains because these experiences increase the likelihood of obesity, inflammation, and traumatic events, all of which are risk factors for poor health and wellbeing, affecting brain structure and thus brain health.

The researchers examined MRI brain scans from approximately 21,000 adult participants aged 40 to 70 years in UK Biobank, as well as information on body mass index (an indicator of metabolic health), CRP (a blood marker of inflammation) and experiences of childhood maltreatment and adult trauma.

Using a type of statistical modelling that allowed them to determine how these interactions work, the researchers confirmed that experiencing childhood maltreatment made individuals more likely to have an increased body mass index (or obesity) and experience greater rates of trauma in adulthood. Individuals with a history of maltreatment tended to show signs of dysfunction in their immune systems, and the researchers showed that this dysfunction is the product of obesity and repeated exposure to traumatic events.

Next, the researchers expanded their models to include MRI measures of the adult's brains and were able to show that widespread increases and decreases in brain thickness and volume associated with greater body mass index, inflammation and trauma were attributable to childhood maltreatment having made these factors more likely in the first place. 

These changes in brain structure likely mean that some form of physical damage is occurring to brain cells, affecting how they work and function.