Learning Objectives

After this webinar, clinicians should:

1.    Recognize the importance of distinguishing the 3 Ds of geriatric psychiatry
2.    Identify the clinical criteria of delirium and understand its variable presentation in older adults
3.    Differentiate between delirium superimposed on dementia and dementia-only
4.    Understand treatment modalities for delirium, dementia, and depression in older adults.

[Transcript edited for clarity]
Welcome to the Carlat Psychiatry webinar on distinguishing the 3Ds in older adults. I'm Stephanie Collier, Editor-in-Chief of The Carlat Geriatric Psychiatry Report. I have no financial disclosures related to this material.

Today we're going to learn about the importance of distinguishing among the 3Ds of geriatric psychiatry, which are delirium, dementia, and depression.

We'll also review the clinical criteria of delirium and how it may present in older adults, learn how to differentiate between dementia and delirium imposed on dementia, and review the treatment options for delirium, dementia, and depression in older adults.

Case

“Ms. B” is an 80-year-old retired microbiologist with generalized anxiety disorder, mild neurocognitive disorder, a history of stroke, and recent COVID-19 pneumonia. She reports new memory concerns, two minor car accidents, difficulty initiating activities, and insomnia.

You wonder whether Ms. B's mild neurocognitive disorder has progressed to dementia, whether she's delirious, or whether this is depression. Perhaps this is just the lingering effects from COVID-19 infection.

So how can you narrow down her diagnosis?

Introduction: 3 Ds: Delirium, Depression, Dementia

I start the 3Ds with delirium for a reason, as it's a life-threatening clinical syndrome. Think of delirium as acute brain failure. Although it's been described for over 2,500 years, it's still missed in about two-thirds of older adults, or it's misdiagnosed as the other 2Ds, which are depression or dementia.

Delirium is characterized as a neurocognitive disorder, but it has cognitive and non-cognitive features.
Its noncognitive features include disruptions to a patient's sleep-wake cycle, motor activity, and changes in mood and behavior. Delirium is a clinical diagnosis, and it's often missed because it can look like anything in psychiatry. Patients with hypoactive delirium may appear depressed.

Patients with hyperactive delirium may appear psychotic or manic. And due to its acute presentation, patients with delirium may be suspected of being intoxicated or withdrawing from substances. But it's important to remember that delirium holds a place of diagnostic privilege. You cannot make another psychiatric diagnosis in its presence.

Still, delirium can be superimposed on dementia, and in any older adult with delirium, it's okay to suspect an underlying dementia until proven otherwise.

What about the overlap of the other Ds?

Well, depression and apathy are the most common affective symptoms of dementia, so keep an eye out for it. However, if you suspect a person with dementia is depressed, make sure to first rule out delirium. Then there's the dementia syndrome of depression, what used to be called pseudodementia. This is when the cognitive changes in depression are mistaken for dementia.

To distinguish between the three Ds with our overlapping symptoms, it's often most helpful to first focus on the onset, duration, course, orientation, and attention to make the right diagnosis.

Comparing the 3 Ds 

In any patient in whom you suspect one or more of the three Ds, you need to figure out their baseline functioning and when the symptoms started. To determine a patient's baseline, you'll need to get collateral, usually from family members or caregivers. You want to know whether they need help in performing their activities of daily living, like bathing or showering, dressing, getting in or out of a chair, going to the bathroom, and eating.

Next, and probably one of the most important pieces in differentiating among the three Ds, is finding out when the symptoms started. Delirium has a rapid onset.
Patients develop a change in mood or behavior in a matter of hours or days.

This is very different from depression, which you wouldn't diagnose until a patient experiences at least two weeks of symptoms, and sometimes it can take a few months to appreciate a gradual worsening of mood.

And dementia has a very gradual onset. Patients may have had a gradual decline over months or years. The duration of symptoms can help you differentiate among the three Ds. Delirium can resolve in a few weeks, whereas a depressive episode can take months or longer to resolve. Dementia persists for years to decades.

In terms of testing cognition, it helps to focus on three areas: orientation, attention, and consciousness. Let's start with orientation. People with depression should be oriented. If this is impaired, think about delirium. People with dementia may have preserved orientation in the early stages, although they gradually lose orientation. First to time, then to place, and finally to person.

To test attention, you can do serial sevens. Ask the patient to spell "world" backwards, or my personal favorite: ask the patient to tell you the months of the year backwards. Remember, in delirium, impairment in attention happens first, and it's the last to resolve. People with depression should not demonstrate difficulties with attention, and attention is preserved in the early stages of dementia as well.

Finally, look at a person's level of alertness. If a patient is hypoactive or hyperactive, basically anything besides being awake and alert, especially if this waxes and wanes throughout the day, this points you toward delirium.

Psychosis in the 3 Ds

What if your patient experiences symptoms of psychosis? Chances are that psychosis in an older adult without a prior diagnosis of schizophrenia would be due to one of the three Ds.

Let's start with delirium. Psychosis in delirium is generally related to confusion about the environment, like misperceptions and illusions, interpreting a shadow or light as something else. By contrast, people with dementia may experience hallucinations, which are most often visual hallucinations, as well as delusions and delusional misidentification. The psychosis of depression is more complex and mood congruent. Patients with depression often experience delusions of guilt or nihilism.

Delirium prevalence

Now that we understand how the three Ds may present, let's learn about each D, starting with delirium. How common is it? Well, in the community, delirium is quite rare.

Probably fewer than 2% of older adults are delirious. However, it's been estimated that between 4 and 38% of patients in nursing homes and up to a third of hospitalized older adults experience delirium.

If you're seeing an older adult who's hospitalized for a medical reason or has had a recent medical hospitalization, there's a high chance that patient psychiatric symptoms are either due to or exacerbated by delirium.

Recognizing delirium is so important, as the most common causes of delirium are reversible. There are many risk factors for delirium, which increase with age and frailty. But the main ones for a psychiatrist to consider are cognitive impairment and psychiatric illness.

Delirium is related to brain resiliency.

If a healthy 20-year-old has a UTI, they most likely won't develop delirium.

However, in an 80-year-old patient with dementia and multiple medical conditions, this might be enough to push the patient into delirium.

Other important risk factors are medical comorbidities, hearing or visual impairment, trauma, surgery, substance use, and medication use or withdrawal.

When seeing a patient for the first time, you might notice confusion, but differentiating between delirium and dementia becomes tricky.

Chances are that if your patient has new confusion, it's delirium.

Treat it as such by minimizing factors that could worsen the patient's mental state. Review their medications and pay particular attention to anticholinergic medications, benzodiazepines, and pain medications.

Then, rule out medical causes. Infections like UTIs or pneumonia are the most common cause of delirium in older adults, but also think about a coronary event or stroke, electrolyte imbalances, renal insufficiency, or thyroid dysfunction. Although dementia and depression can co-occur with delirium, you want to avoid attributing the patient's symptoms to other Ds before ruling out delirium.

For example, you want to make sure the patient is consistently attentive before assuming their symptoms are due to depression. In making the diagnosis of delirium, you want to always specifically test for attention.

Say you have a patient who tries to state the months of the year backward and gets stuck around September after a few attempts.

This would not be consistent with depression, and you want to make sure you communicate to everyone around that the patient is not inattentive due to depression. Screening the patient with a four-question confusion assessment method or CAM can be helpful in detecting delirium.

There are a couple of domains that could point you toward a diagnosis of delirium.

If the patient has confusion, if the patient's symptoms fluctuate, like they look different in the morning than in the evening, if their attention is impaired, and if there's altered consciousness.

You may be wondering, what's altered consciousness?

That's anything besides being alert and awake.

Patients might be hyperactive and agitated, or they may be dozing off before you, their eyes closing while you are trying to talk with them. That's altered consciousness.

Even if you're really sleep deprived, your eyes would generally remain open during a conversation with your doctor.

When you see this, think about hypoactive, hyperactive delirium, the more common subtype of delirium in older adults.

Unfortunately, it carries a worse prognosis than the hyperactive type, which is often picked up earlier and frequently seen in alcohol withdrawal.

So now that you've identified delirium, how do you treat your patient?

If you're thinking about using an antipsychotic, melatonin, or cholinesterase inhibitor to treat or prevent delirium, think again. These medications have not been shown to prevent or treat delirium or improve outcomes. However, if your patient is agitated to the point of harming themselves or others, or if they're experiencing significant distress related to hallucinations or delusions, then you can consider using an antipsychotic.

Although antipsychotics don't improve the course or outcomes of delirium, they can temporarily calm the patient down and relieve distress related to psychosis.

It's better to treat and prevent delirium with non-medication options by targeting risk factors. This might sound vague, given the many risk factors for delirium, but you want to think systematically about what you can optimize.

Encourage patients to get out of bed. Recommend PT or OT to help their daily functioning. Make sure patients have their glasses, hearing aids, and dentures, and attend to your patient's pain.

When hospitalized, clinicians should avoid the use of restraints and bed alarms, which have been shown to increase the risk and persistence of delirium and injury.

I also want to highlight paying attention to the patient's environment, which should be conducive to sleep at night.

The most common non-cognitive function disturbed in delirium is the sleep-wake cycle, and disturbances in sleep occur in 97% to 99% of all delirious episodes.

Let's move on to dementia.

Dementia is a term used to describe the loss of memory, language, problem-solving abilities, and other cognitive functions that are so severe they interfere with a person’s daily life.

The most common type of dementia is Alzheimer’s disease, but you also need to think about vascular dementia, Lewy body dementia, and frontotemporal dementia. Although diagnostic criteria vary between the types of dementia, delirium is actually a strong risk factor for dementia and a potentially modifiable risk factor. The more episodes of delirium a person has, the higher the likelihood that they develop dementia.

Each episode of delirium increases a person’s dementia risk by 20%.

How do you treat dementia? Well, ideally, you do everything you can to prevent an older adult from developing dementia in the first place.

You know that 40% of a person’s dementia risk is attributable to 12 modifiable risk factors.

These are: less education, hypertension, hearing impairment, smoking, obesity, depression, physical inactivity, diabetes, low social contact, and the three newest risk factors—excessive alcohol consumption, head injury, and air pollution.

As you can see, you can optimize many of these risk factors.

Once a patient progresses to cognitive impairment, you can treat them with anti-amyloid monoclonal antibodies, which are the new disease-modifying treatments.

Finally, you may need to think about tertiary treatments or treating symptoms once they develop, such as agitation.

So where does late-life depression come in?

Late-life depression is often characterized by diurnal mood fluctuation, rather than the intense and rapid fluctuation in symptoms seen in delirium.

Importantly, late-life depression is associated with cognitive impairment.

There’s a bi-directional relationship with dementia.

Depression is a known risk factor for dementia and for Alzheimer’s disease in particular. One theory is that depression results in hypercortisolemia, which may cause hippocampal damage, increasing a person’s susceptibility to developing dementia.

Indeed, older adults with depression may demonstrate hippocampal atrophy on imaging.

The reverse relationship may also hold true.

Dementia might cause late-life depression. Late-life depression is often thought to be part of a dementia prodrome. A patient might experience a first depressive episode months or even a year before they develop noticeable cognitive impairment.

Regardless, late-life depression often includes the dementia syndrome of depression.

Patients with severe depression might experience difficulties remembering. They may be inattentive, struggle with motivation, and even have word-finding difficulties.

People with dementia syndrome of depression demonstrate more impairment in executive function, especially task switching and set shifting, compared to those with Alzheimer’s disease.

This can be picked up in neuropsych testing and can help differentiate between depression and dementia.

It’s important to recognize and treat late-life depression, as it severely affects a patient’s quality of life.

You can treat late-life depression with medications, psychotherapy, neuromodulation, or lifestyle interventions.

But keep in mind that once late-life depression is comorbid with dementia, non-drug interventions are often more efficacious.

In patients with depression and dementia, try social prescribing—linking your patients to non-drug interventions in their community.

Social prescribing has been shown to not only reduce symptoms of depression but also loneliness and social isolation.

Non-drug interventions are more efficacious than medications for treating depressive symptoms in dementia. Interventions with good data behind them include reminiscence therapy, increasing exercise, animal therapy, and massage and touch therapy.

In patients with dementia, try to reserve antidepressants for those with a history of major depressive disorder or for patients with serious behavioral disturbances that aren’t responding to other interventions. Keep in mind the potential harms of antidepressants in older adults, including an increased risk of falls and fractures.

When depression is accompanied by psychosis, you might consider adding an antipsychotic if the benefits are felt to outweigh the risks. You might also consider cholinesterase inhibitors to manage some of the behavioral and psychological symptoms of dementia.

We’ve seen the overlap in symptoms between delirium, dementia, and depression. Thankfully, there’s overlap in their management. In patients with any of the 3Ds, always prioritize investigating for reversible causes, especially if there’s a change in the quality or severity of their symptoms.

Think about how to optimize the safety of the patient and provide supportive care.

Don’t forget to ask about and treat pain. Make sure they’re eating and drinking and going to the bathroom regularly. Teach family members how to redirect and reorient the patient, and explore what they can do to calm the patient down. Working with caregivers on effective communication strategies can go a long way in reducing agitation and behavioral challenges.

Brainstorm how to get creative with a patient’s environment, especially if you’re concerned about wandering.

We’ve seen that medications really aren’t that helpful in treating delirium or reducing depressive symptoms in dementia, but at what point should you consider medications? In general, you want to reserve psychiatric medications for treating a patient’s distress, such as when they are agitated or psychotic.

Don’t use medications to sedate the patient. You want the patient alert and awake, which is a different goal than, for example, treating a younger patient with mania or psychosis, where your goal would be sedation. Ideally, you want to control a patient’s symptoms with only one medication and at the lowest effective dose.

Once a patient’s symptoms are controlled, try to taper off the psychiatric medication. It’s very possible that their symptom exacerbation was due to either a medical or social stressor. If a patient requires a PRN medication regularly to calm down, try to schedule that medication. You never want to get behind agitation or severe distress or anxiety. Ideally, you want to prevent distress from happening.

When sundowning occurs, whether from delirium or dementia, try to provide any psychiatric medication at night to help with the sleep-wake cycle disturbances.

Let’s return to our case of Ms. B. When deciding between the three Ds, you want to first rule out delirium. You order lab tests and a basic medical workup, which come back unrevealing. You test her attention, which is intact.

You know she has a mild neurocognitive disorder, so you repeat the MoCA to look for progression.

Her MoCA comes back as a 24 out of 30, which is similar to her score last year. You assess for changes in her IADLs by speaking with her family members. They tell you she’s still preparing her food and managing her finances. She’s shopping for groceries and doing housework. She’s no longer a nurse. She’s using her phone.

Finally, you assess for depression.

You screen with the geriatric depression scale, which comes back positive with a score of 10 out of 15. You go through the SIGECAPS criteria with her. And although Ms. B denies feeling depressed, she admits to anhedonia, guilt, poor sleep and appetite, low energy, concentration problems, and difficulty initiating activities. You diagnose Ms. B with the dementia syndrome of depression.

Let’s wrap up and review the main points about delirium, dementia, and depression.

First, when thinking through the three Ds, timing and the duration of symptoms provide the strongest clues. When someone’s mental status changes quickly, think about delirium. Still, delirium often co-occurs with dementia.

Assume a person with delirium has a less resilient brain and consider monitoring their cognition after the episode of delirium has resolved. When symptoms persist, you want to make sure to think about medical comorbidities. Just because a patient’s UTI was treated doesn’t mean it can’t come back.

After an episode of delirium, assume any future changes in your patient’s mental state are due to a medical reason until proven otherwise and test their attention if you’re unsure.

Finally, delirium, dementia, and depression all affect cognition.

Regularly monitoring patients at risk, which is most older adults, with different MoCA versions, for example, can help you detect early changes.

I cannot emphasize the importance of obtaining a cognitive baseline on all of your older patients enough.

Thank you for joining me today.

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