PRESS: Predictors of the development of suicidal thoughts and behaviors in a longitudinal design. An evaluation of the Interpersonal Theory of Suicidal Behavior

• Applicants: Professor Dr. Thomas Forkmann; Professorin Dr. Heide Glaesmer; Professor Dr. Georg Juckel; Privatdozent Dr. Tobias Teismann
• Subject Area: Personality Psychology, Clinical and Medical Psychology, Methodology
• Term: from 2016 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 288645884

Mental disorders, depression, hopelessness, low socio-economic status, and a polymorphism of the serotonin-transporter-gene (5-HTTLPR) are risk factors that predict heightened risk for suicide. However, these risk factors´ explanatory value for suicidal behavior is limited. Recently, the Interpersonal Theory of Suicide (ITS) has been proposed. It assumes that the simultaneous occurrence of Thwarted Belongingness (TB; the perception of not being part of a valued group) and Perceived Burdensomeness (PB; the perception of being a burden for others) predicts suicidal wishes. If then TB and PB occur together with the Acquired Capability for Suicide (AC) suicidal attempts may be predicted. An ever-growing number of studies has been published that are in concordance with the assumptions of the theory. Nevertheless, so far there are (a) no significant prospective studies available and (b) no studies have been published that try to prove the incremental predictive power of TB, PT and AC as compared to established biopsychosocial risk factors. The main research question of the present study is whether the variables PB, TB, and AC predict suicidal attempts when controlling for established biopsychosocial risk factors. We further aim to investigate antecedents, amplification processes and positive feedback loops between TB, PB, and AC and the relations between AC, pain perception and the 5-HTTLPR polymorphism in a longitudinal design. The entire project lasts 30 months. In a prospective design we aim to recruit N=260 patients within two weeks after they were admitted to a psychiatric or an emergency ward (eight clinics and one emergency ward at three places) because of suicidal attempt or acute suicidality. Patients´ suicidal thoughts and behaviors, mental disorders and risk factors will be assessed using structured interviews and questionnaires. Moreover, pain perception (pressure algometer) and the 5-HTTLPR polymorphism (saliva samples) will be determined. Patients will be re-assessed with questionnaires and interviews after 6 (T1), 9 (T2) and 12 (T3) months (T1-2 telephone interviews, T3 home visits including assessment of pain perception). Data analyses will include multilevel analyses for longitudinal data, multivariate analyses of variance, regression analyses, structural equation models and the auto-correlation/cross-correlation approach (SPSS, AMOS, HLM, EGRET). The project will provide the most important necessary information to allow for a deeper and more comprehensive understanding of suicidal developments based on the ITS. The results of the project will further bear important implications for risk assessment, crisis intervention and treatment of suicidal thoughts and behavior.

• DFG Programme: Research Grants