I recently had the opportunity to review an evaluation authored by a fellow neuropsychologist in a forensic matter in order to author a rebuttal report. The opposing neuropsychologist argued that the reason the middle-aged gentleman he evaluated, a man a year post a moderate traumatic brain injury (TBI) with significant accompanying physical problems, had not returned to work was because he was depressed and had developed “learned helplessness”, but not at all because of his continued, residual brain injury related impairments. Putting aside the current debate about whether our default brain state is to believe we are capable or helpless in the face of adversity, the primary issue is whether or not there is sufficient science to support the claim made by this neuropsychologist, specifically that mental health problems manifesting post injury were the source of this man’s continued challenges and were not at all related to his TBI. I did not think so. In this Forensic Update I will briefly review relevant literature about mental health challenges for people recovering from TBI.
In an article published in 2018 in an issue of the Journal Brain Injury, a group of researchers followed a thousand adults over a two-year period with a broad range of severity of traumatic brain injury. Over fifty percent of these individuals, three months post injury, reported clinically significant levels of depression. These individuals also had higher levels of post concussive symptoms versus psychosocial global outcome ratings. Not surprisingly, previous psychiatric history was a contributing but not primary factor. Further, those with a normal CT scan showed higher risk to develop depression than those with mild CT abnormalities. This is consistent with the clinical observation that most people with mild brain injury attempt to return to normal life despite being compromised, often leading them to struggle. This finding is similar to earlier studies over the past 20 years identifying the significant increased risk in developing depressive symptoms following a traumatic brain injury.
In a multi-site study completed in 2003, feeling hopeless, worthless and experiencing difficulty enjoying activities were the three symptoms that most differentiated depressed from non-depressed patients following TBI. A 2004 review of the research available up to that time also reflected the significant presentation of depression post TBI, noting that depression was often poorly understood and treated among acute care and rehabilitation professionals working with individuals with TBI. One reason for this is the lack of clear etiological models for the development of depression following TBI. It is likely that there are multiple pathways and clinical implications. In a continued follow up of this population at a year post TBI, 41 percent were still depressed. The researchers concluded that pre-injury personality and coping mechanisms appeared to be more important to determining long-term outcome than the severity of the physical injury itself.
In a very large, recent study published just a year ago, over 200,000 adults with histories of traumatic brain injury were matched to controls over a 24-month period. This study highlighted the importance of long-term monitoring for depression post TBI. Incidence of depression post TBI when excluding individuals with a history of pre-TBI depression was 79.5 per thousand persons compared to 33.5 per thousand persons for those without a history of TBI. This would suggest that there is a nearly three times greater probability that someone with a TBI will develop depression than someone in the general population.
Even beyond the issue of depression is the concern about any type of mental health disorder after a traumatic brain injury. In a sample of nearly 300 adults evaluated and followed in a rehabilitation program over six months in New Zealand, nearly 60% noted significant psychological problems post-injury. Yet, only 9% had a confirmed psychiatric diagnosis and only 2% were working with a mental health professional. In this sample, only 10% of this group demonstrating psychological problems post-injury had a history of psychological disorders pre-injury. Very clearly the rate of all mental health problems is significantly higher post-traumatic brain injury than pre-traumatic brain injury and, as this study demonstrates, few of these individuals were receiving any intervention or support.
Finally, a study completed by Jennie Ponsford twenty years ago examining the myriad of factors influencing outcome following mild traumatic brain injury, while demonstrating that by three months post-injury many of the symptoms reported at one week had largely resolved and no significant impairments were evident on neuropsychological measures, there was a subgroup of nearly one out of four participants who were still suffering many symptoms. These people were highly distressed. Further they reported that their lives were still significantly disrupted. Interestingly, these individuals did not suffer from longer periods of post-traumatic amnesia. They were however more likely to have a previous history of head injury, neurological or psychiatric problems, be females and to have been physically injured in a previous motor vehicle accident. The majority of this group at three months post-accident were still demonstrating significant levels of problems of what would be considered psychopathology. This small study demonstrated that a range of factors other than those directly relating to the severity of injury appear to be associated with outcome following mild TBI.
There is an increasing trend among my forensic colleagues to include citations and peer reviewed literature to support the opinions in their reports. In part, the impetus for this process was a change in rules for experts in Utah requiring experts to provide any sources they “relied upon” in forming their opinions. When cited in a forensic report an evaluator tacitly acknowledges that he or she relied on these studies in forming their opinions. From my perspective, after forty years of practice I have arrived at the conclusion that this is an extremely slippery slope. One can never be certain that all relevant scientific literature has been reviewed, presented and critiqued. Further, many studies purporting to measure the same topic, often do not agree. Finally, citation of a single study, particularly when most research studies possess limitations from design and statistical perspectives may not be any better than simply offering one’s opinion based on training, experience and qualifications. When asked, I now inform counsel that I am happy to provide research studies that in some part or completely support my opinions; however, I do not rely on those studies to form my opinions. My opinions, as the courts have determined, are based upon my training, qualifications and experience.
Is it much of a stretch to appreciate that when someone’s life is disrupted by any event, whether a TBI or other significant physical injury or adverse life experience, an event that confronts a person with the inability to control the course of their life and their destiny, that they are at risk to develop depression and feel helpless or hopeless? I think not. In light of the available research, it appears likely that a significant contributor to these and the broad range of mental health symptoms individuals with TBI experience are a direct consequence of their TBI, physical injuries and changes in life activities. Further, it appears pseudoscientific when such individuals present with psychological symptoms to argue that their pre-accident history (which in fact may have made them more vulnerable than others to adversity after injury) is the primary reason for their current problems or that their mental health symptoms are the sole cause of their difficulties independent of the consequences of their injuries. As well, for that matter, we must demonstrate intellectual restraint when these individuals demonstrate inconsistent effort on our testing. Sometimes they may truly be malingering. However poor or inconsistent performance, even that placing the individual as a statistical outlier, is not always a sign of malingering and dissimulation but may equally be a consequence of the development of hopeless and helpless beliefs in the face of post-accident challenges and experiences.
References
Risk of depression after traumatic brain injury in a large national sample. Journal of Neurotrauma, 36, 300-307.
Gibson, R., & Purdy, S.C. (2015). Mental health disorders after traumatic brain injury in a New Zealand caseload. Brain Injury, 29, 306-312.
Moldover, J.E. et al. (2004). Depression after traumatic brain injury: a review of evidence for clinical heterogeneity. Neuropsychology Review, 14(3), 143-154.
Ponsford, J., Willmott, C., et al. (2000). Factors influencing outcome following mild traumatic injury in adults. Journal of the International Neuropsychological Society, 6, 568-579.
Seel, R.T. et al. (2003). Depression after traumatic brain injury: a National Institute on Disability and Rehabilitation Research Model Systems multicenter investigation. Archives of Physical Medicine Rehabilitation, 84(2), 177-184.
Singh, R. et al. (2017). Prevalence of depression after TBI in a prospective cohort: The SHEFBIT Study. Brain Injury 2018, 32, 84-90.
Singh, R. (2019). Comparison of early and late depression after TBI. Brain Injury. doi.org/10.1080/02699052.2019.1566837.
