19 Conditions that Mimic Dementia


May 23, 2023

mimic dementia

Did you know there are many medical conditions and disorders that can interfere with cognition and mimic dementia? 

If your older adult has been experiencing cognitive challenges or acting strangely, it’s natural to think Alzheimer’s disease or dementia might be the cause. After all, we hear so much about it in the news. Plus, a recent AARP survey found that nearly half of adults 40 and older think they will develop dementia — a share far greater than the condition’s actual prevalence.

However, it’s important to not jump to the conclusion that it’s a non-treatable condition like dementia because there are many treatable diseases that mimic dementia. That’s why it’s essential to visit a doctor as soon as you realize there’s a problem. There could be something relatively simple going on that they can treat.

Delirium can fool even experienced doctors into misdiagnosing dementia.
It comes on rapidly, often after a medical or surgical event or toxic combination of medications. It is accompanied by shifting alertness, resulting in moments of sleepiness alternating with moments of agitation. Its causes are many and include infection, metabolic disturbances, toxic medication reactions, withdrawal from alcohol, and the effects of head injury, just to name a few.
* Delirium can often be reversed once the cause is found and treated.

Thyroid disease – The thyroid makes hormones that keep every system in the body running smoothly. But too little or too much thyroid hormone could cause dementia-like symptoms. A primary care doctor or an endocrinologist can use a simple blood test to measure thyroid levels. Because Thyroid disease develops slowly, it’s symptoms are often mistaken for normal aging.
* Thyroid problems can usually be treated with medications, but sometimes require surgery.

Medication – Has the older adult recently started a new medication? Older adults are more likely than younger people to develop cognitive impairment as a side effect of a medication, and drug toxicity is the culprit in as many as 12 percent of patients who present with suspected dementia. Taking too many medications (called polypharmacy) can affect your ability to think clearly and remember things. Even a prescription you’ve been on for many years can trigger confusion. The reason is your kidneys and liver become less effective at clearing drugs from your body as you get older, so a medication can build up in your system and cause problems.
* Ask your physician or pharmacist to conduct a “Medication Review” to discuss harmful side effects and decrease unnecessary medications and interactions.

Head TraumaStarting at the top of the body, head injury tops the list because of the risk of trauma to the brain. A fall, even one that seemed less serious, can be followed by significant cognitive problems. When this is due to a concussion, symptoms usually improve over time with supportive care. A limited post-traumatic bleed inside the skull can interfere with cognitive functioning by leading to a collection of blood called a subdural hematoma.

Diabetes – If your older adult has undiagnosed diabetes, it could be causing their memory problems, confusion, irritability, or lack of concentration. That happens because the body needs a certain amount of glucose (sugar) to keep blood vessels functioning properly. Too much or too little glucose damages blood vessels in the brain and causes dementia-like symptoms.
*Catching this problem early and getting proper treatment is essential for reversing the symptoms. Ask your older adult’s doctor to test for diabetes.

Alcohol abuse – Over time, heavy drinking destroys brain cells in areas that are critical for memory, thinking, decision-making, and balance. It could also lead to an unhealthy diet that doesn’t include essential vitamins like B-1 – a severe deficiency in B-1 can cause confusion, memory loss, hostility, and agitation. Sometimes the effects of long-term alcohol abuse can be reversed. If this might be causing cognitive issues, speak with your older adult’s doctor about treatment options.

Vision or hearing problems – When someone can’t see or hear well, their behavior can make it seem like they have dementia. And if those problems are left untreated, they can become more and more isolated, which could actually cause cognitive impairment. To prevent this problem, get regular eye exams and regularly ask your older adult’s doctor or an audiologist to screen for hearing issues.

Tumors – Brain tumors, malignant or benign, can seem like dementia – especially with slow-growing tumors. They can interfere with the brain’s functioning and also result in personality changes.

Urinary tract infections – UTIs are another common cause of delirium and dementia-like symptoms in older adults. Like respiratory infections, UTIs manifest differently in those older than 65 than in younger patients. For example, an older adult with a UTI might experience a mental status change without a fever or burning with urination.
* The good news is most UTIs, and the accompanying cognitive issues, can be diagnosed with a simple urine test and treated with an antibiotic.

Sleep problems or disturbed sleep – Getting a good night’s rest is essential for protecting the brain as you age. Sleep gives our brain time to learn, store memories and filter out toxic substances. If your sleep-wake cycle is disturbed or you have insomnia, you may experience dementia-like symptoms such as trouble focusing, confusion, mental fatigue and irritability. Insomnia affects 30 to 48 percent of older people. If you are struggling to get shut-eye, experts recommend limiting or eliminating daytime naps, restricting the use of alcohol and caffeine in the evening and following a consistent sleep schedule and other good sleep hygiene habits. If those remedies don’t work, cognitive behavioral therapy can help. If you are diagnosed with sleep apnea, using a continuous positive airway pressure machine (CPAP) while you snooze has been shown to be an effective treatment, Ellison says.

Dehydration – Dehydration can look like dementia, and it’s common in older patients. As you age, your body’s ability to retain water in blood vessels decreases, and your thirst mechanism isn’t as strong, so it’s easy to get dehydrated without realizing it. If you take diuretics or laxatives, they can further contribute to water loss. If the older adult seems foggy or confused, check to see if their urine is dark yellow or brown, which can indicate a lack of fluids. Another sign of severe dehydration is a white coating on the tongue. Intravenous fluids can often reverse cognitive problems caused by severe dehydration. 
* To prevent dehydration, older adults should aim to get at least 48 ounces of caffeine-free fluids (six 8-ounce glasses) a day.

Infection – Any untreated infection can cause delirium – a sudden change in alertness, attention, memory and orientation that can mimic dementia. When you have an infection, the white blood cells in your body rush to the infection site, causing a chemical change in the brain that makes some older adults feel drowsy, unfocused or confused. This is very common in respiratory infections.
* This is completely treatable if you get to the trigger or underlying source of the infection.  

Normal Pressure Hydrocephalus Another condition that can create cognitive impairment is normal pressure hydrocephalus (NPH), a disorder in which cerebrospinal fluid accumulates in the ventricles (cavities) of the brain and interferes with thinking, memory, walking, and control of urination.

Problems with Vision and HearingSensory limitations, too, can create a picture like cognitive impairment that worsens as the affected person becomes increasingly isolated as a result of hearing or vision problems. Recent research has emphasized that there is a relationship between hearing loss and the risk for development of cognitive impairment.

Disorders of the Heart and Lungs – The heart and lungs provide the brain with oxygen and nutrients that are necessary for proper functioning. Age is often accompanied by vascular (blood vessel) disease that interferes with cardiac output or lung disease that interferes with the delivery of oxygen to the brain. These underlying diseases can cause MaND as well as what’s commonly known as vascular dementia (which can sometimes occur along with Alzheimer’s-related dementia). They can also affect alertness, memory, and executive function.

Liver and Kidney Disease – Diseases of the kidney or liver can result in an accumulation of toxic metabolic waste products in the blood, dulling the mind or poisoning mental activity and sometimes resulting in Major Neurocognitive Disorder.

Hormone Disruption – Disorders of the endocrine organs, responsible for making hormones that are transported through the bloodstream in order to control many metabolic activities, are additional causes of Major Neurocognitive Disorder-like symptoms. An excess or deficiency of thyroid hormone interferes with thinking. Disturbances in the regulatory effects of insulin, a hallmark of diabetes mellitus, harm cognition along with other bodily functions.

Cancers – Some cancers are associated with cognitive and behavioral changes. These can occur through local effects of a tumor (for example by invading or compressing brain tissue) or as a result of tumor effects on the immune system in which antibodies against the brain are formed, producing a “paraneoplastic syndrome”.

Toxic Metals – Heavy metal toxicity, too, can create more stable changes that could go unrecognized without specific testing.

How Doctors Make an Accurate Diagnosis

Fortunately, many of these medical conditions are treatable and some are even curable. An assessment for Major Neurocognitive Disorder should always include tests to look for these treatable conditions so that no patient has to suffer needlessly from an untreated and debilitating condition. The mental status examination should give clues to the presence of a delirium or certain other medical disturbances, and this examination is followed up by physical examination and tests of the blood and urine.

Blood count, thyroid tests, kidney functions, liver enzymes, metabolic screening, and urinalysis are routine elements of the Major Neurocognitive Disorder diagnostic workup. Lyme or syphilis tests, lumbar puncture, heavy metal screen, urine culture, chest X-ray, EEG, or neuroimaging with MRI and/or PET scanning may be appropriate tests for patients whose symptoms suggest the need for these additional, more costly, and sometimes more invasive tests.

Sources: AARP Health; Brightfocus Foundation; Dailyhearing.com

We hope this information is helpful to you in the important work you do as a family caregiver.
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