The Role Of Pain Processing In The Relationship Between Childhood Physical Abuse And Non-suicidal Self-injury Behaviors Among Middle School Students

Objective This study is aim to investigate the relationship between childhood physical abuse and non-suicidal self-injury behaviors, to examine the role of pain processing(pain coping style and pain perception) in the relationship between childhood physical abuse and non-suicidal self-injury behaviors among middle school students.Methods A total of 14,820 middle school students were selected from junior and senior middle schools in Zhengzhou, Guiyang and Bengbu city. Information relating to demographics, psychopathological status, different types of adverse childhood experiences, and NSSI were obtained. Rates on childhood abuse and NSSI were compared in students with specific characteristics. Logistic regression was used to analyze relationships between each form of adverse childhood experiences and NSSI.A total of 5 116 middle school students in Bengbu city, among those the pain coping style questionnaire were appended. Pearson’s correlation analysis was used to test the relation between pain coping style and childhood physical abuse and the frequency of non-suicidal self-injury behaviors. Multi-variable linear regression analysis and Sobel test were used to analyze the potential mediating effect of pain coping style in the relationship between childhood physical abuse and non-suicidal self-injury behavior.A survey of childhood abuse and non-suicidal self-injury behaviors was administrated among six hundred and thirty nine middle school students. A total of 120 students were divided into 4 groups, with 30 students in each group, according to the childhood physical abuse and non-suicidal self-injury, matched by class and gender. Pain threshold and pain tolerance were measured at baseline and after stress induction task. Variance analysis and covariance analysis were used to analyze the difference of pain threshold and pain tolerance between 4 groups.ResultsRates of physical abuse, emotional abuse, sexual abuse, emotional neglect, physical neglect, family dysfunction and total adverse childhood experiences were 20.3%, 45.7%, 13.3%, 64.2%, 58.5%, 42.5%, 89.4%, respectively. Girls had significantly greater exposure to emotional abuse(P < 0.001), and boys had significantly greater exposure to physical abuse, sexual abuse, emotional neglect, physical neglect, and total adverse childhood experiences(P<0.001), while no gender differences were found in exposure to family dysfunction(P>0.01). A total of 3 137(26.1%) students reported that they had engaged in NSSI in the past 12 months. The rate of NSSI reported significantly higher among male students than female students(P<0.001). The findings also indicated that grade, father’s and mother’s education, perceived family economical status, perceived learning burden, number of intimate friends and psychological status were important concomitants of NSSI. Multivariable logistic regression analysis showed that, after controlling for demographics psychological status, any type of adverse childhood experiences appeared as independent risk factors on NSSI and significant graded relationship was found between number of adverse childhood experiences types and NSSI(P <0.001) among male and female middle school students.Mediating effect test results showed that general and negative pain coping styles played partial mediating effect on the associations between childhood physical abuse and the frequency of NSSI, while no mediating effect of positive pain coping styles was found. The proportions of mediating effects in total effects of general and negative pain coping styles were 9.3% and 25.0%, respectively. The proportions of mediating effects in total effects of general and negative pain coping styles were 5.2% and 13.2%, respectively after controlling for demographics, psychopathological status. The mediating effects of negative pain coping style was significant for boys or girls, but the mediating effects of general pain coping style was significant for girls only.On the whole, the pain threshold and pain tolerance threshold among students with childhood physical abuse and non-suicidal self-injury were the highest, while among those with neither childhood physical abuse nor non-suicidal self-injury were the lowest. The pain threshold at baseline among students with childhood physical abuse and non-suicidal self-injury was significantly higher than those with non-suicidal self-injury but without childhood physical abuse. Pain threshold and pain tolerance among students with neither childhood physical abuse nor non-suicidal self-injury at baseline and after stress induction task were significantly lower than other groups. The differences between groups were not influenced by negative affect and BMI.Conclusions The findings suggest that middle school students with childhood physical abuse and other adverse childhood experiences are a group with elevated risks for NSSI. NSSI prevention programs should focus on the adverse and target attenuating the severity of adverse childhood experiences.It also show that childhood physical abuse may lead to higher pain threshold and pain tolerance, and the lack of effective pain coping styles, thereby increasing the risk of non-suicidal self-injury behaviors. Clarifying such intermediaries in the relationship between childhood physical abuse and non-suicidal self-injury is valuable because targeting and modifying negative pain coping styles may contribute to the reduction or cessation of NSSI.