Current research

Affective symptoms (eg, depression, anxiety) following traumatic brain injuries including concussion are common.2 However, it is estimated that only 6% of patients experience some form of depression following the concussion.3 Recent consensus statements on SRC have called for more research exploring the emotional sequelae that may accompany SRC as well as appropriate assessment and treatment approaches.2 ,4 Researchers have indicated that affective responses, particularly depression, are common following concussion.5–9 However, it is important to note that most affective responses occur at a subclinical level that does not meet diagnostic criteria for a clinical disorder. Additionally, it is important for the clinician to be aware of any pre-existing psychological conditions that may affect the emotional responses following SRC.

Both psychosocial and neurobiological factors may help to explain affective responses following SRC. For example, individuals with clinical depression have been found to exhibit structural and morphological changes of the brain's mood centres involving the hippocampus,10 amygdala and prefrontal brain regions,11 which may be affected after concussion. Frustration over uncertain recovery time, isolation from teammates and sport, and lack of social support may result in emotional responses following SRC. Injury to mood-related areas of the brain including the hippocampus, amygdala and prefrontal areas following SRC may also result in altered mood. Recently, researchers have begun to try to disentangle affective responses related to SRC from those resulting from general psychosocial and behavioural responses that occur following any injury. Much of this research has focused on comparing the affective responses of athletes with SRC to those with orthopaedic injuries. Although some researchers have reported different emotional sequelae for athletes with SRC compared to those with musculoskeletal injuries,6 Covassin et al 5 noted similar state and trait anxiety between athletes with concussions and those suffering orthopaedic injuries. Additionally, some research has reported that females endorse more affective symptoms than males following concussion.8 Overall, research has supported an increase in depression and overall mood disturbance following SRC in collegiate athletes.9 Increased depressive symptoms have been noted up to 14 days postinjury in both high school and collegiate athletes.7 Risk factors, such as age may play a role in the presence and duration of affective symptoms, as collegiate athletes have reported significantly more depressive symptoms at 14 days postinjury compared to high school athletes.7 However, in the same study, sex differences were not supported. Nonetheless, the role of risk factors such as sex and concussion history on affective symptoms following SRC warrants attention from researchers.

Assessment

Clinical researchers advocate for a comprehensive approach to assessing concussion including clinical interviews, symptom scales, neurocognitive testing, and balance, vestibular and oculomotor screening.1 In many cases, an athlete's responses and behaviour during the clinical interview may provide the first indication of a mood disturbance following concussion. Biopsychosocial and family medical histories that may be gathered during the clinical interview can also provide the clinician with an understanding of the athlete's personal and familial risk factors, including underlying affective tendencies, and environmental/situational factors that may exacerbate these responses. A comprehensive clinical interview can also help establish the foundation for a therapeutic alliance between the athlete and clinician, allowing the athlete to feel more comfortable discussing changes in mood following SRC that they may be otherwise hesitant to reveal. The clinical interview is an integral part of the assessment of SRC. The use of symptom scales may also help the clinician evaluate mood disturbance, as most symptom scales for SRC include items representing affective symptoms, such as anxiety and depression. Evidence of affective responses following SRC warrants more in-depth evaluation using clinical measures, such as the State-Trait Anxiety Inventory, Profile of Mood States, and Beck Depression and Anxiety Inventories. Additional referrals to mental health practitioners for more in-depth assessment may also be indicated.

Anecdotally, some athletes with vestibular impairment following SRC develop concurrent anxiety related to the pathophysiology of central vestibular impairment as well as the subjective perception of their impairments. For example, an individual with vestibular impairment may experience vertigo, dizziness or fogginess in complex visual-vestibular environments (eg, at school, while driving), which can provoke an anxiety response. This anxiety, if not identified and treated appropriately and early, may progress and disrupt recovery and the effectiveness of other treatments. As such, vestibular screening should also be included in a comprehensive assessment of athletes with SRC.

Treatment

Treatment for athletes with SRC should be targeted and based on the results of a comprehensive assessment.1 Treatment for athletes with mood-related and anxietyrelated profiles following SRC often involves behavioural management interventions including a regulated sleep schedule, proper nutrition and hydration, as well as overall stress reduction and physical activity.1 For athletes experiencing subclinical mood changes, such as nervousness or sadness, helping the athlete to identify and talk about the aetiology of the symptoms can be helpful. For example, many athletes experience these symptoms in response to an inability to play their sport or participate in school or work, or concern over potential length of recovery.

If an athlete experiences affective symptoms secondary to vestibular impairment as described above, the vestibular dysfunction should be addressed first using appropriate vestibular therapies.12 The athlete may need to be referred to a specialist (eg, vestibular therapist, otolaryngologist) to confirm vestibular dysfunction and begin treatment. Once vestibular symptoms and impairment have resolved, the athlete may begin to increase physical activity. If there are mood changes in the absence of a vestibular component, it is helpful to begin physical activity as soon as possible. The introduction of a structured physical activity plan is a key component in the overall reduction of anxiety in these individuals, as physical exertion can provide an emotional release, as well as decrease the overall level of arousal.1

Most athletes do not require formal treatment for affective symptoms following SRC, particularly as they begin to recover and return to normal levels of activity. However, there are athletes for whom the affective symptoms are more prominent and begin to adversely affect the recovery process and move into clinical territory. It is with these athletes that psychotherapy or medication management may be a useful intervention. Therefore, for athletes with clinical levels of depression or anxiety following SRC, referral to appropriate mental health practitioners (eg, clinical psychiatrist) specialising in the care of these disorders may be indicated. However, concurrent follow-up and management should still be coordinated with the referring clinician to ensure the best clinical outcome following SRC for these athletes.

Future research

Research exploring the emotional sequelae following concussion is currently in its infancy. Although some research has supported an inverse relationship between social support and state anxiety,5 very little research has explored the role of social support and coping skills. Additionally, recent findings suggest that depression following concussion may be associated with increased postconcussive symptoms, as well as decreased performance on neurocognitive measures.7 However, more research on this relationship is warranted, as is additional investigation of the role of SRC on subsequent clinical levels of depression and anxiety. Further research should also explore which risk factors may be associated with affective symptoms following SRC, as well as the presence of mood disturbance more than 14 days postinjury. More research is warranted exploring age and sex and the emotional sequelae following SRC. Additionally, more research should be conducted to explore the effect of pre-existing psychiatric diagnoses on the emotional sequelae. Finally, researchers should also begin to investigate the efficacy of behavioural and other interventions on athletes with affective symptoms following SRC.