“Doctor, do you diagnose dementia? Because I need someone who can diagnose dementia.”
A man asked me this question recently. He explained that his 86 year-old father, who lived in the Bay Area, had recently been widowed. Since then the father had sold his long-time home rather quickly, and was hardly returning his son’s calls.
The son wanted to know if I could make a housecall. Specifically, he wanted to know if his father has dementia, such as Alzheimer’s disease.
This is a reasonable concern to have, given the circumstances.
However, it’s not very likely that I — or any clinician — will be able to definitely diagnose dementia based a single in-person visit.
But I get this kind of request fairly frequently. So in this post I want to share what I often find myself explaining to families: the basics of clinical dementia diagnosis, what kind of information I’ll need to obtain, and how long the process can take.
Now, note that this post is not about the comprehensive approach used in multi-disciplinary memory clinics. Those clinics have extra time and staff, and are designed to provide an extra-detailed evaluation. This is especially useful for unusual cases, such as cognitive problems in people who are relatively young.
Instead, in this post I’ll be describing the pragmatic approach that I use in my clinical practice. It is adapted to real-world constraints, meaning it can be used in a primary care setting. (Although like many aspects of geriatrics, it’s challenging to fit this into a 15 minute visit.)
Does this older person have dementia, such as Alzheimer’s disease? To understand how I go about answering the question, let’s start by reviewing the basics of what it means to have dementia.
5 Key Features of Dementia
A person having dementia means that all five of the following statements are true:
- A person is having difficulty with one or more types of mental function. Although it’s common for memory to be affected, other parts of thinking function can be impaired. The 2013 DSM-5 manual lists these six types of cognitive function to consider: learning and memory, language, executive function, complex attention, perceptual-motor function, social cognition.
- The difficulties are a decline from the person’s prior level of ability. These can’t be lifelong problems with reading or math or even social graces. These problems should represent a change, compared to the person’s usual abilities as an adult.
- The problems are bad enough to impair daily life function. It’s not enough for a person to have an abnormal result on an office-based cognitive test. The problems also have to be substantial enough to affect how the person manages usual life, such as work and family responsibilities.
- The problems are not due to a reversible condition, such as delirium, or another reversible illness. Common conditions that can cause — or worsen — dementia-like symptoms include hypothyroidism, depression, and medication side-effects.
- The problems aren’t better accounted for by another mental disorder, such as depression or schizophrenia.
Dementia — now technically known as “major neurocognitive disorder” — is a syndrome, or “umbrella” term; it’s not considered a specific disease. Rather, the term dementia refers to this collection of features, which is caused by some form of underlying damage or deterioration of the brain.
Alzheimer’s disease is the most common underlying cause of dementia. Vascular dementia (damage from strokes, which can be quite small) is also common, as is having two or more underlying causes for dementia. For more on conditions that can cause dementia, see here.
What Doctors Need to Do To Diagnose Dementia
Now that we reviewed the five key features of dementia, let’s talk about how I — or another doctor — might go about checking for these.
Basically, for each feature, the doctor needs to evaluate, and document what she finds.
1. Difficulty with mental functions. To evaluate this, it’s best to combine an office-based cognitive test with documentation of real-world problems, as reported by the patient and by knowledgeable observers (e.g family, friends, assisted-living facility staff, etc.)
For cognitive testing, I generally use the Mini-Cog, or the MOCA. The MOCA provides more information but it takes more time, and many older adults are either unwilling or unable to go through the whole test.
Completing office-based tests is important because it’s a standardized way to document cognitive abilities. But the results don’t tell the doctor much about what’s going on in the person’s actual life.
So I always ask patients to tell me if they’ve noticed any trouble with memory or thinking. I also try to get information from family members about any of the eight behaviors that are common in Alzheimer’s. Lastly, I make note of whether there seem to be any problems managing activities of daily living (ADLs) and instrumental activities of daily living (IADLs).
2. Decline from previous level of ability. This feature can be hard for me to detect on my own during a single visit. To document a decline in abilities, a doctor can interview other people, and/or document that she’s reviewed previous cognitive assessments. I have also occasionally documented that a patient is currently unable to correctly perform a cognitive task that is related to her career or education history. For instance, if a former accountant can no longer manage basic arithmetic, it’s reasonable to assume this reflects a decline from previous abilities.
3. Impairment of daily life function. This is another feature that can be tricky to detect during a single visit, unless the patient is very impaired. I usually start by finding out what kinds of ADLs and IADLs help the person is getting, and what kinds of problems have been noted. This often means talking to at least a few people who know the patient.
Driving and managing finances require a lot of mental coordination, so as dementia develops, these are often the life tasks that people struggle with first.
In some cases — usually very early dementia — it can be quite hard to decide whether a person’s struggles have become enough to qualify as “impairment of daily life function.” If someone isn’t taking his medication, is that just regular forgetfulness? Ambivalent feelings about the medication? Or actual impairment due to brain changes? If I’m not sure, then I may document that the situation seems to be borderline, when it comes to impairment of daily life function.
4. Checking for reversible causes of cognitive impairment. I mentally divide this step into two parts. First, I consider the possibility of delirium, a very common state of worse-than-usual mental function that’s often brought on by illness. For instance, I’ve noticed that older people are often mentally assessed during or after a hospitalization. But that’s not a good time to try to definitely diagnose dementia, because many elders develop delirium when they are sick, and it can take weeks or even months to return to their previous level of mental function.
(My approach to considering dementia in older adults who are confused during or after hospitalization: Make a note that they may have underlying dementia, and plan to follow-up once the brain has had a chance to recover.)
After considering delirium, I check to see if the patient might have another medical problem that interferes with thinking skills. Common medical disorders that can affect thinking include depression, thyroid problems, electrolyte imbalances, B12 deficiency, and medication side-effects. I also consider the possibility of substance abuse.
Checking for many of these causes of cognitive impairment requires laboratory testing, and sometimes additional evaluation.
If I do suspect delirium or another problem that might cause cognitive impairment, I don’t rule out dementia. That’s because it’s very common to have dementia along with another problem that’s making the thinking worse. But I do plan to reassess the person’s thinking at a later date.
5. Checking for other mental disorders. This step can be a challenge. Depression is the most common mental health problem that makes dementia diagnosis difficult. This is because depression is not uncommon in older adults, and it can cause symptoms similar to those of dementia (such as apathy, and poor attention). We also know that it’s quite common for people to have both dementia and depression at the same time.
In many cases, there may be no easy way to determine whether an older person’s symptoms are depression, early dementia, or both. So sometimes we end up trying a course of depression treatment, and seeing how the symptoms evolve over time.
It’s also important to consider the older person’s mental health history. Paranoia and delusions are quite common in early dementia, but could be related to a mental health condition associated with psychosis, such as schizophrenia.
Is it Dementia or Mild Cognitive Impairment?
Sometimes, when an older person is having memory problems or other cognitive issues, they end up diagnosed with “mild cognitive impairment.”
Mild cognitive impairment (MCI) means that a person’s memory or thinking abilities are worse than expected for their age (this should be confirmed through office-based cognitive testing), but are not bad enough to impair daily life function.
The initial evaluations for MCI and dementia are basically the same: doctors need to do a preliminary office-based cognitive evaluation, ask about ADLs and IADLs, look for potential medical and psychiatric problems that might be affecting brain function, check for medications that affect cognition, and so forth.
I explain more about MCI in this article: How to Diagnose & Treat Mild Cognitive Impairment.
But remember: in practical terms, if an older person’s memory problems have gotten bad enough that he can’t grocery shop the way he used to, or she can no longer manage her finances on her own…those qualify as impairment in daily life function. And so, a diagnosis of “mild cognitive impairment” is probably not appropriate for those cases.
To learn more about the difference between mild cognitive impairment, Alzheimers and dementia, watch this video:
Can Dementia Be Diagnosed During a Single Visit?
So can dementia be diagnosed during a single visit? As you can see from above, it depends on how much information is easily available at that visit. It also depends on the symptoms and circumstances of the older adult being evaluated.
Memory clinics are more likely to provide a diagnosis during the visit, or shortly afterwards. That’s because they usually request a lot of relevant medical information ahead of time, send the patient for tests if needed, and interview the patient and a family member (or other knowledgeable “informant”) extensively during the visit.
But in the primary care setting, and in my own geriatric consultations, I find that clinicians need more than one visit to diagnose dementia or probable dementia. That’s because we usually need to order tests, request past medical records for review, and gather more information from the people who know the older person being evaluated. It’s a bit like a detective’s investigation!
Can Dementia be Inappropriately Diagnosed in a Single Visit?
Sadly, yes. Although it’s common for doctors to never diagnose dementia at all in people who have it, I have also come across several instances of busy doctors rattling off a dementia diagnosis, without adequately documenting how they reached this conclusion. (It’s also common for them to hardly document anything in terms of the older peron’s cognitive state, other than “confused, didn’t know date.”)
Now, often these doctors are right. Dementia becomes common as people age, so if a family complains of memory problems and paranoia in an 89 year old, chances are quite high (at least 60%, according to UpToDate) that the older person has dementia.
But sometimes it’s not. Sometimes it’s slowly resolving delirium along with a brain-clouding medication. Sometimes it’s depression.
It is a major thing to diagnose someone with dementia. So although it’s not possible for an average doctor to evaluate as thoroughly as the memory clinic does, it’s important to document consideration of the five essential features of dementia that I listed above.
If You’re Worried About Possible Alzheimer’s or Dementia
Let’s say you’re like the man I spoke to recently, and you’re worried that an older parent might have dementia. (Remember, most dementia is due to Alzheimer’s or a similar underlying brain condition.) You’re planning to have a doctor assess your parent. Here’s how you can help the process along:
- Obtain copies of your parent’s medical information, so you can bring them to the dementia evaluation visit. The most useful information to bring is laboratory results and any imaging of the brain, such as CAT scans or MRIs. See this post for a longer list of medical information that is very helpful to bring to a new doctor.
- Write down worrisome behaviors and problems, and bring this documentation to the visit. You can start with this list of 8 behaviors to track if you’re concerned about Alzheimer’s.
- Consider who else might know how your parent has been doing and behaving recently: other family members? Close friends? Staff at the assisted-living facility? Ask them to share their observations with you and jot down what they tell you. Share these notes, along with the names of the informants, with your parent’s doctor.
- Be prepared to explain how your parent’s abilities have changed from before.
- Be prepared to explain how your parent is struggling to manage daily life tasks, such as work, house chores, shopping, driving, or any other ADLs and IADLs.
- Bring information about any recent hospitalizations or illnesses.
- Bring information about any history of depression, depressive symptoms, or other mental illness history.
By understanding what it takes to diagnose dementia, and by doing a little advance preparation when possible, you will improve your chances of getting the evaluation you need, in a timely fashion.
Watch this Youtube video to learn six ways getting evaluated for memory loss benefits an older person and their family:
And if you have an aging parent who is refusing to get evaluated for memory loss or other concerning symptoms: my free online training for families (see below) covers how to get past this, and includes a nifty PDF summarizing what to say and not say to your parent who may have dementia.
This article was first published in 2015, and was last updated by Dr. K in April 2022.
I’m unsure how you can have a full discussion about diagnosing Alzheimer’s without mentioning the lumbar puncture. Spinal fluid is taken from the spine in a painless 20 minute procedure and then sent to a lab. If the protiens beta amyloid and tau are detected, these are the markers for Alzheimer’s. There is no other diagnosis. Once a reliable diagnosis is made, definitive preparations for living can be made. New symptoms are easily and quickly identified and a patient can engage strategies to overcome them. (For instance, rather than trying harder to think and getting increasingly frustrated by not remembering things, a patient can develop a system of reminders.) This is what I am doing and my life is much better for it, than what it would have been had I not known what was happening to me.
Nicole Didyk, MD says
Thanks for sharing your experience and it sounds like it’s been a positive one for you.
You’re correct that “biomarkers” or levels of certain protein in the CSF (cerebrospinal fluid) can support the diagnosis of Alzheimer’s disease, along with an assessment of symptoms and overall health. Lumbar puncture, aka spinal tap isn’t as accessible as it could be, and similarly, analysis of CSF for those biomarkers isn’t available in a widespread way. Most guidelines about dementia diagnosis and treatment don’t include CSF biomarkers as part of the criteria to make a diagnosis. There’s a good scientific article about that, that you can check out here: https://www.sciencedirect.com/science/article/pii/S1552526016329636#:~:text=Therefore%2C%20the%20diagnostic%20criteria%20for%20AD%20dementia%20established,underlying%20cause%20of%20a%20dementia%20syndrome%20is%20AD.
In addition to those limitations, there are those who argue that finding Alzheimer’s earlier is not worthwhile, since we don’t currently have a medical treatment that will reverse or cure Alzheimer’s. I appreciate hearing your perspective that you were grateful for this information, though and we need to consider the views of patients and families as we decide how to diagnose and treat Alzheimer’s and other dementias.
In the future, CSF testing might be a bigger part of dementia diagnosis, but currently, it’s mostly on the sidelines. Thanks again for weighing in with your story and I wish you all the best.
This is a wonderful resource. Both of my parents are experiencing cognitive issues.
My mother is fairly advanced with dementia. She can’t hold a conversation and basically repeats herself. She forgets that we have visited her. She has stopped bathing and it is a battle to get her to eat.
My father wants to take care of her but he has recently started struggling with his memory. His memory issue displays as a struggle to find the words and connect his thoughts to make sense. It is different from my mother. He also struggles with severe dizziness. This is a big problem because it keeps him from being active and is really impacting him. He can’t look up or take big steps because he will fall. They have been testing him and even thought he had hydrocephalus. We can’t get clear answers and we are still getting tested and changing medication to try to clear up the dizziness but I feel so much of these issues come from being with my mom all day (they have lost all of their friends) and he basically has the same conversation all day long with her. Whatever gets in her head is replayed all day. I also feel he has depression which he has not received treatment for yet. I want to talk to his doctor about this.
Do you know what other diagnosis present with memory trouble (formulating words and communicating) along with dizziness?
I plan to address this with his doctor. I am also planning to move them closer to me and look for a home for my mother. She requires more assistance than my father or I can manage.
Nicole Didyk, MD says
It sounds like you have a lot on your plate with your aging parents!
I want to recommend Dr. K’s book: “When Your Aging Parent Needs Help: a geriatrician’s step-by-step guide to memory loss, resistance, safety worries and more”, and you can find out ore here: https://betterhealthwhileaging.net/education-and-support/when-your-aging-parent-needs-help/ Although you’ve been helping your parents for a while, and the book is mostly from the perspective of starting to help, I think the advice abut how to set priorities and have pivotal conversations is valuable to someone in your situation.
Dizziness is tough to iron out at times, and it can sometimes have multiple causes. Medication adjustments can often help, but it’s frustrating to take the time to make those changes slowly and safely. Some of the symptoms ou describe make me think of Parkinson’s disease, and I’m sure his medical team has considered this.
You might also be interested in our article about depression: https://betterhealthwhileaging.net/depression-in-aging-diagnosis-and-treatment/
Whatever is causing your father’s symptoms, I’m sure that being a caregiver for a person with advancing dementia is a strain, and I suspect you’re on the right track planning for more help and a move. Best of luck and thanks for taking the time to comment.
Karlene Cameron says
I am looking for the free online training and PDF summarizing what to say to a parent who is resisting being evaluated for dementia. I cannot find it on your website. Thanks
Nicole Didyk, MD says
Hi Karlene! I’m so glad you’re interested in learning more! At the bottom of the article, before the comments section is a box with a yellow banner you can click on to sign up for the course. It will open up a box (provided you haven’t disabled pop-ups on your computer) where you can sign up.
If that doesn’t work, try this link: https://betterhealthwhileaging.net/helping-older-parents/
My dad had a PET scan of the brain to help come up with his Alzheimer’s dx. I am not hearing that as part of others’ comprehensive work-up for dementia. It is $$ so not sure if that is why which would be unfortunate
Nicole Didyk, MD says
You’re correct that PET scans and amyloid PET imaging (which can measure the amount of amyloid in the brain) can be helpful in telling the difference between Alzheimer’s and other types of dementia, or Alzheimer’s and such conditions as depression.
Unfortunately, these tests are costly and not as widely available as they could be, so not accessible for all who may be living with Alzheimer’s.
Hi, so I’m 20 years old with OCD and I think I’m kinda going crazy. One year ago I developed very aggressive “brain fog”, I feel like I’m in a state of confusion, I can’t focus and I feel like I went through a cognitive decline overall in the last few years, to a point where I struggle to do simple tasks as well. So recently I read some studies which claim that people with OCD have higher risk of developing dementia compared to people who don’t have OCD and now I’m even more convinced that I’m developing dementia. I also talked with a neurologist and basically he said that I’m too young to eventually develop a neurodegenerative disease but somehow I’m still worried. I also have to add that my grandma has Alzhaimer, which makes me worry even more.
Nicole Didyk, MD says
I can understand being worried about developing dementia, and it sounds like your OCD has caused you to have symptoms that resemble those we see in people living with Alzheimer’s. I did come across this small study in Taiwan that found an association between dementia risk and OCD diagnosis, but this isn’t enough evidence to draw a conclusion: https://pubmed.ncbi.nlm.nih.gov/34004091/.
The biggest risk factor for Alzheimer’s disease, the most common cause of dementia, is older age. Even genetic factors, such as having a grandmother with AD is not as high a risk as simply living a long time.
If you’re worried about developing dementia, now is the time to commit to lifelong healthy habits, like exercise, not smoking, rating a healthy diet and building a strong social network. These habits can help with mental health symptoms as well.
L R GARNER says
My 94yo Mother has lived in an Independent Living Facility for more than 4 years after losing her home to a fire. Recently, when speaking with her she mentions (1) people parking, turning their lights, shining them in her window, and looking into her bedroom — Therefore, Blackout curtains were installed; (2) She states possibly rats are running around the end of her bed at nights (states she can feel them running across her feet at night). She then hit the bed and they stop — More than 4 family members have dismantled her room and bed and nothing was found, My mother’s health is impeccable, she has Type1 Diabetes and wear glasses due to glaucoma. Sees her doctor on a regularly and takes her medication and inputs her eye drops as prescribed. I personally feel this is due to loneliness and/or social isolation. This is not something she will admit too, because she loves her independence. She’s visited regularly by other family and church members and appears to enjoy that time and when they leave.
Can the doctor please advise on what questions I can ask my mother or a better way to communicate when these types of conversations come up or questions or comments are made? I hope I provided the right information to understand my questions.
Thanks in Advance.
Nicole Didyk, MD says
It sounds like your mother might be experiencing hallucinations. This can be a part of dementia in older adults, as I discuss in this YouTube video:https://youtu.be/cjj6NyuPyCI, but can also be related to misperceptions of natural phenomena, distortions from impairments in hearing, vision or the sensory nerves, or part of a delirium.
If this is fairly new, a review by her doctor specifically around this symptom is a good idea, if you haven’t already.
When your mother tells you about her experiences, a good approach can be to validate her perceptions (even if you suspect they are not real) and reassure her that you’re doing everything you can to keep her safe. Then move on to a more pleasant topic. It’s often counterproductive to try to convince the person that, for example, there are no rats. A delusion or hallucination is usually very hard to shake, and efforts to “prove” that it’s a false belief are almost always unsuccessful.
Thank you for the article. I live in India with my parents and grandmother. My grandmother is 90 she had very little auditory hallucinations last year but she recently had a fall which hurt her head and caused her to bleed. We got a CT scan done which showed a small subdural hemmorage. Given her age and how small the injury is a neurosurgeon adviced that the injury is small and would not need a surgery. Fortunately her drowsiness and other symptoms of hemorrhage have reduced.
However, her hallucinations have gotten a lot worse. She now has a lot of visual and auditory hallucinations such as hearing it rain all the time, seeing kids, her relatives with whom she has conversations with, ditches on the floor etc. recently she also hallucinates seeing dirt on her hands which she keeps trying to wash using 2 to 3 buckets of water.
My grandmother was never a great sleeper but after the head injury and once her drowsiness disappeared she constantly wakes up in the night and keeps talking (she hallucinates a lot of situations and keeps having her conversations) and now she also wants to wash her hands in the night because she sees dirt on her hands.
My parents and I haven’t been able to sleep at all properly a few weeks now because of this situation. Can you doctor please advise on what to do at home that could help in this situation. Thank you very much 🙏
Nicole Didyk, MD says
I’m sorry to hear about your grandmother’s fall and injury.
When I see an older adult who’s had a fall and subdural hemorrhage, it’s common that it’s a setback cognitively and can lead to deliriumdelirium. If symptoms are worsening, I would consider seeing the doctor again to make sure nothing else is going on.
Otherwise, in a situation like this, I would advise trying to keep the routine as predictable as possible. Keep the environment calm and familiar. ensure adequate hydration and take the usual medications.
There are medications for hallucinations, but they can worsen drowsiness and have other side ffects, so we usually try to avoid them. You can read more about that here: