Post-traumatic stress disorder mistaken for behavioural and psychological symptoms of dementia: case series and recommendations of care.

In late life, traumas may act cumulatively to exacerbate vulnerability to post-traumatic stress disorder (PTSD). PTSD is also a risk factor for cognitive decline. Major neurocognitive disorder (MND) can be associated with worsening of already controlled PTSD symptoms, late-life resurgence or de novo emergence. Misidentifying PTSD symptoms in MND can have negative consequences for the patient and families. We review the literature pertaining to PTSD and dementia and describe five cases referred for consultation in geriatric psychiatry initially for behavioural and psychological symptoms of dementia (BPSD), which were eventually diagnosed and treated as PTSD in MND subjects. We propose that certain PTSD symptoms in patients with MND are misinterpreted as BPSD and therefore, not properly addressed. For example, flashbacks could be interpreted as hallucinations, hypervigilance as paranoia, nightmares as sleep disturbances, and hyperreactivity as agitation/aggression. We suggest that better identification of PTSD symptoms in MND is needed. We propose specific recommendations for care, namely: clarifying diagnosis by distinguishing PTSD symptoms coexisting with different types of dementia from a specific dementia symptom (BPSD), gathering a detailed history of the trauma in order to personalise non-pharmacological interventions, adapting psychotherapeutic strategies to patients with dementia, using selective serotonin reuptake inhibitors as first-line treatment and avoiding antipsychotics and benzodiazepines. Proper identification of PTSD symptoms in patients with MND is essential and allows a more tailored and efficient treatment, with decrease in inappropriate use of physical and chemical restraints.