Psychiatric comorbidity refers to the presence of two or more mental disorders in one individual. It is an important concern for professionals as it is associated with a more severe course of illness, poorer prognosis and disproportionally higher levels of functional disability as compared to individuals with only one disorder.
Research and clinical reflections highlight how psychiatric comorbidities for individuals with acquired brain injury (ABI; brain damage caused by events after birth):
- Are relatively common.
- Can remain clinically overlooked.
- Can have a potentially negative impact upon rehabilitation outcomes.
Research indicates that individuals with ABI demonstrate elevated levels of psychiatric comorbidity and associated problems. These include psychiatric diagnoses, increased rates of self-harm and suicide attempts, alcohol and substance misuse problems.
Conversely, a US study demonstrated that those in psychiatric settings are more likely than the general population to have an ABI, more severe ABIs, and multiple ABIs.
These findings demonstrate the complex nature of the relationship between ABI and comorbid psychiatric diagnoses, requiring consideration.
Psychiatric comorbidities may be pre-existing, co-occurring or manifest post-onset. It may be beneficial to consider the varying temporal distinctions in turn and draw reflections upon clinical experience.
Pre-existing
There is some evidence to suggest that pre-existing mental health difficulties and/or personality difficulties (as indicated by three factors; ICD-9 diagnoses, psychiatric medication prescription and psychiatric service utilisation) may increase the likelihood of acquiring a traumatic brain injury.
Additional clinical reflections appear to suggest that consideration of pre-existing psychological difficulties may provide some insight into the predisposing and precipitating factors involved with the ABI’s onset. Such examples include:
- Service users suffering from depression and/or mood instability, may engage in self-harm and/or suicide attempts through ligating and/or overdose. If unsuccessful, such attempts can result in anoxia or hypoxia leading to diffuse neurological damage.
- Patterns of risk behaviour associated with personality difficulties and/or mood instability such as impulsive and/or reckless acts can result in an ABI through accidental injury (e.g. RTA following dangerous or drink driving).
- Factors associated with psychosis may lead individuals to become vulnerable and targeted within the community leading to potential victimisation and physical assaults potentially leading to a TBI.
- A history of substance or alcohol misuse (which has been robustly demonstrated to be highly correlated with mental health and personality difficulties) after acute or chronic abuse, can lead clients to develop alcohol related brain damage (ARBD) such as Korsakoffs syndrome.
All such case examples have been observed within my time in neuropsychiatric services.
Moreover, whilst the onset of a neurological condition may result in a personality change, more often a “disinhibition and an exaggeration of pre-injury personality traits” is observed.
Therefore, consideration of pre-existing difficulties could shed light into the potential reaction to, and engagement with, rehabilitation efforts.
Co-occurring
These are potentially organic changes occurring directly as a result of the injury or illness. These need to be taken into consideration during the recovery stages following the onset of a neurological condition.
During the acute recovery stage, behavioural disturbances including agitation, aggression and confusion are often observed. Moreover, a broad range of emotional and behavioural abnormalities may indicate psychological and psychosocial deficits.
In my experience these are often the most problematic for the individual and for those involved in their care.
The most severe psychiatric disorders are characterised by the presence of one or more of the following symptoms: delusions; hallucinations; serious disorder of thought form; severe disturbance of mood; and sustained or repeated irrational behaviour.
Post-onset
These include post-injury psychological reactions to disability and trauma.
These may be evident immediately in the short-term period directly following onset of the ABI and appear functionally related (e.g. PTSD symptoms following a discrete event), or they may manifest distally in the longer term as a result of subsequent event chains evolving from the injury (e.g. long-term poor self-esteem and depression resulting from loss of job and associated status).
There is considerable psychological and neurobehavioural evidence available which supports the hypothesis that ABI increases an individual’s risk of developing subsequent psychiatric disorders in the long term.
These studies tend to focus upon major psychiatric disorders. Research indicates increased rates of disorders such as major depression, bipolar affective disorder, and generalised anxiety disorder in addition to schizophrenia.
Evidence has also been found to indicate high rates of borderline and avoidant personality disorders in those with ABI.
In my clinical practice this may, in part, explain the high rates of anxiety, low mood, low self-esteem, low motivation and low levels of psychological wellbeing often observed within inpatient ABI settings, and are found to be common in survivors of ABI.
Impact upon rehabilitation
Consideration of the potential impact of the constellation of psychological factors involved with an ABI is central to rehabilitation efforts. However, refection upon ABI services identifies factors which may impede such attempts.
Diagnostic overshadowing is the attribution of an individual’s symptoms to one overarching condition, when such symptoms actually suggest a comorbid condition. This issue is increasingly recognised within the intellectual disability field, and may also be prevalent within ABI.
Relating specifically to TBI, “once a diagnosis is made of a major condition…there is a tendency to attribute all other problems to that diagnosis, thereby leaving other co-existing conditions undiagnosed” (Neurotrauma Law Nexus, 2020).
The presence of specialist neurological professionals trained and experienced in identifying and treating a range of organic disorders may increase the likelihood that presenting symptoms are attributed to a neurological cause.
Professionals may view the client with a ‘neurological lens’, filtering out markers which may indicate psychological and/or emotional difficulties. As such, the main focus of rehabilitation efforts tends to be upon physical and cognitive rehabilitation, with consideration of clients’ psychological and emotional wellbeing remaining unaddressed.
Additionally, the hierarchical structure of the medical model dictates that the clinical areas addressed first are those which are considered to be most ‘severe’, and are often those considered more ‘organic’.
ABI services tend to address the physical, cognitive, psychiatric, and psychological/emotional difficulties, in that order.
This prioritisation process, coupled with least restrictive practice efforts, mean that clients can be reintegrated into the community with outstanding mental health difficulties and psychological/emotional difficulties. With limited and stretched community resources, these needs can ultimately remain unmet.
Conclusion
I believe that clinicians’ experiences shape and colour the lens through which they view their clients. This can at times be a challenge for those coming into a neuropsychiatric field from a mental health background.
With clinicians tending to ‘read’ certain presentations with a behavioural or psychological interpretation rather than an organic one.
For example, considering the potential presence of psychosis for a service user presenting with confusion, bizarre behaviour, and reporting visual hallucinations, rather than immediately referring the individual for a UTI screen or CT scan.
More attention and research into the common psychiatric comorbidities within neuropsychiatric services is needed. Consideration of these comorbidities may serve to guide suitable pathways, inform rehabilitation goals and efforts with the aim of increasing emotional and psychological wellbeing.
This article serves to highlight the need to identify and consider psychiatric comorbidities in the comprehensive and holistic assessment of an individual to increase rehabilitation efficacy.
Dr Sarah Ashworth is a forensic psychologist at Cygnet Grange, a neuropsychiatric rehabilitation facility in Mansfield. For more information please call 01623 669 036 or visit www.cygnethealth.co.uk