Health care professionals working with dementia patients should be aware that a higher-than-average percentage of their patients are likely to have PTSD.

Research has found that people with post-traumatic stress disorder (PTSD) appear to have a higher likelihood of developing dementia than those who do not. A meta-analysis of evidence on PTSD and dementia risk, for example, found that people diagnosed with PTSD are up to twice as likely to develop dementia later in life.

It’s not clear how PTSD increases the risk of dementia. Some suggest it has to do with stress-related changes in the brain and central nervous system, long-term effects of certain medications, or the possibility that decreased social engagement and withdrawal, common effects of PTSD, may negatively impact cognitive reserve and resilience.

Moreover, the association between PTSD and dementia appears to be bi-directional. While PTSD seems to raise the risk for dementia, other studies have found that having dementia raises the risk of developing delayed-onset PTSD.

In some cases, this may reflect the emergence of previously undiagnosed PTSD, or high levels of post-traumatic stress, in patients who have avoided diagnosis and treatment, perhaps fearful of clinical settings, invasive questioning, stigma, or loss of control.

Others may have effectively coped with adverse life events without getting PTSD, only to have it emerge when faced with the stress of dementia-related loss of cognitive function, altered routines, decreased coping ability, need for institutional care, or medical intervention (which can present trauma reminders such as ruptures in personal boundaries, feeling overwhelmed, or being touched in ways that feel unsafe).

It’s also possible that PTSD may be more likely to originate from difficult events after a dementia diagnosis. For example, challenges such as invasive medical care, injury, loss of a loved one, or involuntary relocation may be more difficult for someone with dementia to understand and process and more frightening, potentially elevating the risk of PTSD.

Many symptoms and behaviors associated with dementia and PTSD overlap, making it hard to differentiate between the two. These include things like impaired judgment, memory or concentration, lack of social attunement, withdrawal, hyperreactivity, reduced frustration tolerance, difficulty regulating emotions, exaggerated startle response, increased impulsivity, and heightened susceptibility to environmental and situational stressors.

It’s not surprising, then, that PTSD in dementia patients often goes undiagnosed and untreated. It’s important that health care professionals working with dementia patients identify those with existing PTSD diagnoses, take social histories that assess for known or suspected psychological trauma, and identify those who may have been in professions or situations that put them at higher risk of traumatization.

Adding screening questions for patients or surrogates can be useful. For example: Do you (or your loved one) have any history of psychological trauma? Have you (or a loved one) ever had an experience that made it more difficult to trust others or left you feeling unsafe? Are there behavioral patterns of avoidance? History of nightmares? Chronic hyper-vigilance? Combat?

PTSD is widespread. It affects more than combat veterans, first responders, and survivors of sexual assault. It can be caused by everything from automobile accidents, natural disasters, and falls to exposure to chronic verbal abuse, poverty-related stress, or racially-based harassment.

Ideally, medical teams serving dementia patients would have someone with advanced training in PTSD, but this is often not the case. All staff, however, should be familiar with the signs and symptoms of PTSD and the basics of how trauma reminders work.

Signs and symptoms include intrusive symptoms like nightmares, recurrent distressing memories, and persistent psychological distress; avoidance symptoms where people avoid places, people, or situations associated with trauma reminders; hyper-arousal symptoms such as difficulty managing strong emotions or intense emotional reactions to seemingly neutral events; and negative mood and cognition like depressed mood or negative beliefs about others or oneself.

The nervous system of someone with PTSD gets rewired into a chronic state of high alert. The brain constantly searches, beneath conscious awareness, for dangers associated with a traumatic event, however remote or exaggerated these associations may seem. When one is detected, the body instantly ramps up into an intense fight-flight-freeze response.

These associations, called trauma reminders or triggers, can be sensory (e.g., bright light, loud voices, pain, shortness of breath, heat, or cold). They may be memories (e.g., being humiliated by an authority figure), thoughts (e.g., “I’m unprotected”), or emotions (e.g., fear, anger, helplessness). They may be situational (e.g., crowds, immobilized, partially or fully undressed) or related to states such as confusion or deceased alertness, which may mimic a traumatic event or undermine attempts to stay vigilant.

Consider a patient with dementia who becomes agitated, combative, freezes, or goes into a state of collapse whenever staff attempts to bathe her or provide peri-care. Ordinarily, such behaviors might be attributed to dementia. If they occur at regular times during afternoon or evening care, they may even be seen as indicative of sundowning.

Our understanding changes, though, if we learn the patient survived childhood sexual abuse and has a suspected history of undiagnosed PTSD. What looked like sundowning may be a defensive response to trauma reminders (regardless of whether the patient remembers the abuse since, as one trauma specialist puts it, the body remembers).

This knowledge allows the patient’s care plan to be individualized in ways that sensitize and train staff to avoid or remove potential triggers, adjust patient interactions, especially during high-stress activities, and identify strategies that help the patient calm. It might also help anticipate situations that might cause distress, like having a male care assistant or procedures involving catheterization, enema, blood, or restraint.

Medications might also be reviewed, although, according to the Veterans’ Administration, medication management for patients with co-occurring PTSD and dementia can be challenging since the “evidence base is very weak.” Any suggested pharmacological protocols “are primarily inferences from the separate PTSD and neurocognitive disorders (NCD) evidence bases. This can be very problematic since a medication with known efficacy for PTSD may have questionable utility for NCD – and vice versa.”

Awareness about the higher incidence rates of PTSD in dementia patients and the possibility that PTSD is undiagnosed, screening and gathering trauma-specific information, staff training about PTSD symptoms and how these may entangle with symptoms of dementia, learning about the dynamics of trauma triggers – these are all aspects of trauma-informed care.

According to Mark Lachman, a geriatric psychiatrist, “For those with dementia who have also endured traumatic experiences, the disease often impacts their ability to protect themselves against traumatic memories, and this may result in certain behavioral presentations. Taking a trauma-informed approach when caring for patients ensures we don’t inadvertently re-traumatize them, and results in tailored interventions likely to improve the overall patient experience.”

Though trauma-informed care is increasingly common across health care settings, it is often under-utilized when it comes to people with dementia. This needs to change.

Scott Janssen is a social worker.