The Influence of PTSD on Circadian Rhythm

The correlation between post-traumatic stress disorder (PTSD) and circadian rhythm disorders is bidirectional. Individuals with PTSD often experience disturbances in their sleep patterns, and abnormal rhythms can worsen PTSD symptoms through various biological mechanisms involving hormones and metabolism. Studies in neurobiology have shown that abnormalities in the adrenal axis among PTSD patients result in disrupted cortisol levels, which can directly impact the circadian rhythm control of the suprachiasmatic nucleus (SCN). When the autonomic nervous system is out of balance (with activity in the sympathetic nervous system), it can interfere with temperature regulation and heart rate variability. Imbalance can also lead to a reduction in hippocampus size. Increased amygdala activity affects how we perceive time and process emotions together. At the molecular level, trauma-induced changes in gene function, such as DNA methylation, can affect the regulation of circadian clock genes like BMAL1 and PER3, resulting in disrupted patterns of gene activity. Moreover, inflammation (increased IL6 and TNF levels) and stress from oxidation worsen irregularities in energy processing due to faulty mitochondrial function. Medical approaches have evolved beyond therapies to manage rhythms effectively. In the future, researchers need to further explore how to better improve the circadian rhythm disorder of PTSD patients according to the existing shortcomings.