Cognitive, Experiential and Genetic Contribution to Depressive Symptoms in Male and Female Students with a History of Concussion

Abstract

Mild traumatic brain injuries, or concussions, are generally accompanied by a variety of somatic, cognitive and affective symptoms, including depressive-like symptoms.Although for most individuals, the affective symptoms are relatively transient, for others (~ 17 to 44%), these symptoms can persist for extended periods of time. The longer-lasting symptomology appears to depend, in part, on gender, age, prior concussion history and symptom presentation. Accordingly, the purpose of the present study was to examine several cognitive, genetic, and experiential factors which might be associated with depressive pathology among males and females with and without a history of concussion.To this end, male and female university students, ranging in age from 17 to 25, with a history of concussions (n = 105) and a control group of "never-concussed" individuals (n = 214) completed the Wisconsin Card Sorting Task (WCST) to assess executive function as well as several questionnaires assessing cognitive vulnerabilities to depression, early life adversity, and depressive symptomatology. Participants also provided a saliva sample for DNA analysis. Among females, but not males, a history of prior concussions was associated with depressive symptoms, especially among individuals with reduced cognitive functioning as well as greater levels of dysfunctional attitudes and prior history of physical abuse. Furthermore, depressive symptoms were significantly elevated in Caucasian females who reported a concussion and possessed the heterozygous DRD2 C957T (rs6277) genotype compared to those that have not suffered a concussion. The present findings provide further insight into several factors that might contribute to long-lasting depressive pathology following a concussion and the significance of gender.iii