Childhood Trauma May Impact Muscle Function Later in Life

Having traumatic experiences in childhood may impact an individual’s muscular function as they age, a new study has found.

It’s well established that traumatic, stressful experiences early in life are associated with worse health outcomes later on. Thanks to a new study, scientists now have an idea of exactly how that trauma may impact the body over time.

The research, recently published in Science Advances, suggests that those who endure traumatic events in childhood are more likely to suffer from impaired muscular function at age 70 or older.

Researchers analyzed skeletal muscle tissue samples from more than 800 participants to examine whether adverse childhood events — such as physical abuse or emotional abuse — were associated with a change in two measures of muscular function: the production of adenosine triphosphate (ATP), which generates cellular energy; and oxidative phosphorylation, a cellular process that helps generate ATP.

These functions take place in the mitochondria, a part of the cell that is the primary energy source for most biochemical and physiological processes, including growth and movement.

“Recently, mitochondrial function has been implicated as a possible mechanism for understanding how stressful life events ‘get under the skin’ to influence health and physical well-being,” the authors wrote. “Mitochondria are capable of sensing and integrating social stress on a cellular level. In response to psychological stress, mitochondria undergo dynamic changes in their structure, leading to alterations in function.”

Among the 754 participants who fully completed the questionnaire on childhood adverse life events, 53% reported experiencing one or more adverse events in childhood. Among those experiencing three or more events, 55 individuals reported experiencing three events, 29 participants reported four events, 25 participants reported five events, and 8 participants reported experiencing all six events.

Those who experienced at least one traumatic event were found to have worse production of ATP, and each additional event was associated with even lower ATP production. This remained true when accounting for things like sex, age, and physical activity.

Individuals who reported experiencing stressful life events in childhood, on average, also reported a greater number of depressive symptoms.

Mitochondrial function naturally declines with age and is associated with reduced muscle performance, mobility, and frailty in older adults. Therefore, the study results suggest that these early life stressors may contribute to reduced health and quality of life in older adults.

“The results of our study offer preliminary evidence for the specific role that skeletal muscle mitochondria may play in how adverse events become biologically embedded,” the authors wrote. “Future work should examine these findings in the context of other relevant biologic pathways—including, but not limited to, inflammation, cell senescence, and mtDNA mutations—and to what extent other mediating factors may also play a role in shaping energy production among older adults across the life course.”