Study finds teens with self-harm history have a significantly higher pain threshold

Teenagers, who have self-harmed five or more times in their life, have a significantly higher threshold for pain compared to adolescents that have not suggested new research from the Institute of Psychiatry, Psychology, and Neuroscience (IoPPN) at King's College London, in collaboration with Glasgow University.

The study, which has been published in JAMA Network Open, is the largest study of its kind looking at the relationship between self-harm and bodily sensation, found that the threshold for sensitivity, both painful and not, increases significantly the more a participant had self-harmed in the past.

64 participants aged between 12-17 were recruited from a mixture of community and residential care settings, as well as schools and youth groups in London and Glasgow. Each individual underwent a series of 13 tests, including thermal detection and pain thresholds, and pressure pain thresholds to establish at what point they detected a change in sensation or first began to feel pain.

Suicide is the second-highest cause of death among teenagers, and self-harm is the strongest predictor of suicide. The investigators now say that this has the clinical potential to be an effective test for identifying youths that are at the highest risk. Dr. Dennis Ougrin, the study's Co-Lead author from King's IoPPN, said "Rates of self-harm and suicide in children and adolescents has been rising in the UK, and we most commonly see the first episodes of self-harm take place around the age of 12."

"From the studies that we conducted, we can see that teenagers who have self-harmed five or more times in their past have a dramatically higher pain threshold, particularly in individuals that are living in care."

 Young people in care constitute less than 1 percent of the UK under 18 population, yet account for about half the suicides. There is not yet have a reliable biomarker for suicide, but it is something that Dr. Ougrin hopes can change.

"Once a person has become comfortable enough with pain when they have raised the threshold far above what it would normally be in someone that hasn't self-harmed, it is at that point we can say that they are at greater risk of suicide."