Mental Health and ABI: Understanding Dual Diagnosis in Adult Services
Adults living with an acquired brain injury (ABI) often experience mental health conditions alongside cognitive, behavioural and neurological impairment. Understanding dual diagnosis in this context is critical for services delivering safe, lawful and effective support. Within ABI services, mental health needs are rarely separate or secondary; they shape risk, behaviour, engagement and long-term outcomes. This article sits alongside existing guidance on mental health and dual diagnosis in ABI and should be read in the context of wider ABI service models and care pathways.
Dual diagnosis in ABI services refers to the presence of one or more mental health conditions alongside the effects of brain injury. This may include depression, anxiety, post-traumatic stress, psychosis, personality change or substance misuse. Unlike traditional mental health services, ABI support must account for impaired insight, executive dysfunction, emotional regulation difficulties and fluctuating capacity. Failing to recognise this interaction often leads to inappropriate placements, repeated crisis episodes and regulatory concern.
Why dual diagnosis presents differently in ABI
Brain injury alters how mental health conditions present, are experienced and can be supported. Changes to cognition, impulse control and emotional processing mean that symptoms may not align neatly with diagnostic criteria used in mainstream mental health services. For example, low mood may present as withdrawal, aggression or disengagement rather than verbalised depression. Anxiety may manifest through avoidance, rigid routines or heightened risk behaviours.
Services must therefore avoid relying solely on diagnostic labels. Effective ABI provision focuses on functional impact: how mental health needs affect daily living, relationships, safety and decision-making. This approach underpins person-centred planning and prevents over-medicalisation or inappropriate restrictive responses.
Operational example 1: Post-rehabilitation depression and withdrawal
A man in his forties moved into supported living following inpatient neuro-rehabilitation. While physically independent, he became increasingly withdrawn, stopped attending activities and refused support. Initial assumptions focused on “lack of motivation” linked to ABI.
The service worked with a community mental health nurse to reassess presentation. Depression related to loss of identity post-injury was identified. Day-to-day support was adjusted to include structured morning routines, graded re-engagement with meaningful activity and weekly reflective key-work sessions. Progress was evidenced through activity logs, mood tracking and reduced refusal incidents, forming part of ongoing quality reviews.
Operational example 2: Anxiety, risk and repeated crisis presentations
A woman with ABI and a history of anxiety experienced frequent crisis episodes, including calls to emergency services. Staff responded reactively, escalating incidents without recognising underlying triggers.
A multidisciplinary review identified anxiety linked to sensory overload and fear of losing control. The support approach shifted to proactive planning: predictable routines, advance decision-making tools and clear de-escalation strategies. Staff recorded early warning signs and successful interventions, demonstrating reduced crisis contacts and improved emotional regulation over time.
Operational example 3: Substance misuse following ABI
A provider supporting a man with ABI following a road traffic collision noted increasing alcohol use, missed appointments and safeguarding concerns. Rather than exclusion or enforcement, the service worked with substance misuse services and commissioners to adapt the support plan.
Daily support focused on harm reduction, structured engagement and joint reviews. Effectiveness was evidenced through reduced safeguarding alerts, improved attendance at health appointments and documented reflective supervision for staff managing complex risk.
Governance and assurance in dual diagnosis support
Supporting dual diagnosis in ABI requires strong governance. Providers must ensure mental health considerations are embedded within risk management, safeguarding processes and quality assurance systems. This includes regular multidisciplinary reviews, escalation pathways and clear recording of decision-making rationale.
Governance frameworks should demonstrate how learning from incidents, complaints or near-misses informs service improvement. Without this, dual diagnosis becomes a hidden risk rather than a managed reality.
Commissioner expectation
Commissioners expect ABI services to demonstrate integrated responses to mental health need, not reliance on external services alone. This includes clear partnership working, shared risk ownership and evidence that placements remain appropriate as needs fluctuate. Commissioners will scrutinise crisis data, safeguarding trends and outcomes when reviewing value for money.
Regulator expectation (CQC)
CQC expects providers to recognise and respond to mental health needs within ABI services under the Safe and Responsive domains. Inspectors look for evidence that staff understand how mental health and brain injury interact, that restrictive practices are minimised, and that people receive coordinated, person-centred care.
Services unable to evidence this understanding risk findings related to unmanaged risk, inappropriate restraint or failure to meet individual needs.
Outcomes and long-term impact
When dual diagnosis is properly understood and embedded into ABI service delivery, outcomes improve. Individuals experience fewer crises, greater emotional stability and improved quality of life. For providers, this translates into safer services, stronger commissioning relationships and improved regulatory confidence.