Researchers may have identified a biomarker for identifying adolescents at high risk for self-harm, which is a risk factor for suicide.
According to previous studies, a high pain threshold may be associated with self-harm in teens, but it was unclear whether the study participants developed a high pain threshold before or after self-harm. A cross-sectional study published in JAMA Psychiatry explored this association to clarify the connection.
The researchers recruited 64 adolescents aged 12 to 17 years from the London and Glasgow, Scotland, areas. The primary outcome measure was somatosensory sensitivity of participants who lived in residential care and who self-harmed either 5 or more times or 1 to 4 times. The researchers compared the self-harm groups with 2 control groups of youth who did not engage in self-harm. The control participants were both adolescents who resided in the community and those who lived in residential and/or group care. The researchers measured 13 parameters related to painful and nonpainful stimuli.
Comparing pain scores between the groups, the researchers found lower pain sensitivity in the high self-harm group compared with the control groups. The difference between the low self-harm group and the control groups was insignificant. The high self-harm group also had lower sensitivity scores compared with the other groups.
“Our findings suggest that reduced pain sensitivity, evident in response to a broad range of painful stimuli, could be a phenotype of adolescents with self-harm,” the researchers stated. “These findings are novel evidence that these sensory differences also extend to nonpainful stimuli, and adolescents with the most frequent episodes of self-harm show the largest mean nonpain sensory deficit.”
The researchers did not differentiate between subjective response and the neurobiology of physical pain or sensitivity, which is a limitation of this study. The study also included a higher percentage of female participants, and the participants overall were not evenly distributed between groups.
Regardless, the researchers propose pain sensitivity as a biomarker for self-harm, which may help prevent suicide in this population.
Cummins TM, English O, Minnis H, et al. Assessment of somatosensory function and self-harm in adolescents. JAMA Netw Open. Published online July 13, 2021. doi:10.1001/jamanetworkopen.2021.16853