Biological Markers for Suicide Risk
Differential patterns of activity and functional connectivity in emotion processing neural circuitry to angry and happy faces in adolescents with and without suicide attempt.
Pan LA, Hassel S, Segreti AM, Nau SA, Brent DA, Phillips ML.
Suicidal behavior is a leading cause of morbidity and mortality in adolescence. Despite progress in understanding risk factors for suicidal behavior, the pathogenesis is poorly understood, including possible alterations in neural circuitry that might predispose to suicidal behavior. Progress in the prediction and prevention of suicidal behavior would be facilitated by the identification of biomarkers for suicide risk, which could improve our understanding of the pathogenesis of suicidal behavior in order to target and reverse such pathogenic processes. In a study published in the January 2013 issue of Psychological Medicine, Drs. Pan, Phillips, Brent, and colleagues in the Department of Psychiatry examined the extent to which adolescents with a history of both suicide attempt and major depressive disorder (MDD) showed abnormal neural activity while processing emotional faces, compared with adolescents who had a history of MDD but no history of suicide attempt.
The investigators used functional magnetic resonance imaging (fMRI) to measure neural activity in response to emotional faces (angry and happy; and of varying intensity) in three groups: adolescents with a history of both suicide attempt and depression; adolescents with a history of depression alone; and a group of healthy controls. Results showed that to 50% intensity angry faces, adolescents with a history of suicide attempt showed significantly greater activity than depressed adolescents without a history of suicide attempt in anterior cingulate gyral-dorsolateral prefrontal cortical attentional control circuitry, primary sensory and temporal cortices; and significantly greater activity than healthy controls in the primary sensory cortex. In contrast, depressed adolescents without a history of suicide attempt had significantly lower activity than healthy controls in the anterior cingulate gyrus and ventromedial prefrontal cortex. Using psychophysiological interaction analyses, the study also revealed significantly reduced anterior cingulate gyral-insula functional connectivity to 50% intensity angry faces in adolescents with a history of suicide attempt than both other groups.
Taken together, these findings suggest that adolescents with a history of suicide attempt may show inefficient recruitment of attentional control neural circuitry when regulating attention to mild intensity angry faces, which may represent a potential biological marker for suicide risk.
Lisa Pan, MD, Anna Maria Segreti, BS, Sharon Nau, MS, David Brent, MD, and Mary Phillips MD, MD (Cantab). (Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center)
Stephanie Hassel, PhD (Department of Psychiatry, University of Calgary, Alberta, Canada)