Reversible and Irreversible Cognitive Disorders

For people over 55 years old, the lifetime risk of developing dementia can be as high as 42%. That means almost half the population may struggle with memory loss, confusion, and even personality changes. For their loved ones, this cognitive decline is heartbreaking and leaves many feeling helpless.

While dementia can mean permanent cognitive and functional decline, many people don’t realize that some cognitive disorders can be reversed with proper treatment. This article will briefly explore the differences in symptoms, causes, and treatment options in reversible and irreversible cognitive disorders to help families and loved ones make informed decisions. ^[1]

What are Cognitive Disorders?

Cognitive disorders (also called neurocognitive disorders) comprise a category of mental health conditions that primarily affect a person’s cognitive abilities, including their ability to:

• Learn
• Remember or retain information
• Think or process thoughts
• Perceive the world around them
• Solve problems
• Make decisions

The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) categorizes these disorders into several subtypes, including:

• Delirium: A rapid onset of confusion and changes in cognition often triggered by medical conditions or substance use
• Mild neurocognitive disorder: A noticeable cognitive decline that does not interfere excessively with daily life but could be an early sign of more severe disorders
• Major neurocognitive disorder (dementia): A category that includes severe conditions like Alzheimer’s disease

Since this problem encompasses a wide range of disorders, it can manifest in many different ways, including:

• Struggles with short-term memory loss or having difficulty recalling important information
• Challenges in planning, organizing, and executing tasks
• Trouble speaking or understanding language
• Impairments affecting coordination (perceptual-motor skills) and the ability to interpret visual information

These impairments impact one’s ability to function. If one has memory or information processing issues, having a normal conversation or maintaining a relationship can be challenging.

Naturally, cognitive impairment also means problems with work and difficulties completing tasks or meeting deadlines. Similarly, day-to-day activities, like managing finances, cooking, or showering, can gradually become more complex, often requiring the individual to rely on outside sources for help and care.

Not many cognitive disorders can be treated or even completely reversed, so let’s look at those that can.

Reversible Cognitive Disorders

A study in the Journal of Dementia & Neuropsychologia found that nearly 20% of cognitive disorders may have reversible causes, meaning they can be treated. ^[2] These disorders must be diagnosed as early as possible to avoid permanent damage.

The most extreme example is when a person develops delirium, which is marked by extreme confusion, disorientation, memory loss, sudden changes in mood or behavior, and possible hallucinations.

It can be caused by infections, dehydration, or metabolic imbalances (which are problems with the body’s chemical processing, such as blood sugar or electrolyte levels). This condition is typically acute, meaning it develops quickly.

For example, someone with a high fever may become delirious, experiencing disorientation and unusual behavior. Treating the underlying cause—such as rehydrating, managing the infection, or correcting a metabolic issue—can quickly resolve delirium.

Nutritional deficiencies, particularly in vitamin B12, can cause “brain fog,” difficulty focusing, and memory issues. A simple supplement or change in diet can reverse these deficiencies in some cases.

Side effects from certain medications are other common reasons for confusion and memory problems, and seeing a doctor about changing medications or adapting the dosages can help these symptoms.

Several medical conditions, such as thyroid problems, can affect memory and cognitive function. These may also be completely treatable with proper treatments.

Symptoms of Reversible Cognitive Disorders

It’s crucial to identify a reversible disorder as soon as possible so that it may be treated. We’ve highlighted some of the more common symptoms below.

1. People with cognitive disorders might be confused and have trouble understanding what’s happening around them, following conversations, or making decisions. This confusion can come on quickly, especially with conditions like delirium, which infections or medication side effects can trigger.
2. People might have trouble remembering what just happened or learning and retaining new information. Vitamin B12 deficiencies or injuries like concussions can cause this kind of memory loss.
3. Disorientation is also a key symptom. People with disorientation may feel lost, not recognize familiar places, or be unsure about the time or date. Conditions such as thyroid problems or fluid buildup in the brain (hydrocephalus) can cause this, and treating the root cause can help manage the confusion.
4. Simple tasks may seem complicated, and conversations can be hard to follow, as concentrating or focusing can be almost impossible.
5. Finding the right words or understanding when another person is talking can become a problem.
6. Affected individuals may face mood swings, irritability, or unusual behavior.

Irreversible Cognitive Disorders

When a cognitive disorder cannot be partially or entirely reversed and becomes progressively worse over time, it falls under the category of major neurocognitive disorders, which are considered irreversible. ^[4][5]

The table below gives an overview:

Disorder	How It Starts	Common Symptoms	Tests and Signs Doctors Look For
Alzheimer’s Disease	Starts slowly and gets worse over time	Memory loss, trouble with speaking, changes in behavior	Brain scans show abnormal brain protein buildup (plaques/tangles).
Vascular Dementia	Can start suddenly after a stroke or have a gradual onset	Trouble with memory, problem-solving, and thinking that can change day to day	Evidence of strokes or blood flow problems on brain scans
Dementia with Lewy Bodies	Symptoms appear gradually.	Fluctuating alertness, seeing things that aren’t there, movement issues	Special brain scans show changes in brain chemicals.
Frontotemporal Dementia	Gradually, before age 65	Personality changes, trouble speaking or understanding, poor judgment	Brain scans show shrinkage in the front and side areas of the brain.

Symptoms of Irreversible Cognitive Disorders

With progressive and irreversible cognitive disorders, symptoms may be subtle at first and, therefore, overlooked. However, they worsen over time. These are the most common signs:

1. Changes in behavior are usually among the first signs, and they can manifest as a person being increasingly irritable, easily frustrated, and more angered than usual. They may also withdraw from social interactions and lose interest in hobbies and activities. It’s important to note that these changes can be mistaken for other mental health disorders, such as depression.
2. Changes in how a person acts or in their personality may be noticed. You may see higher levels of anxiety or depression (especially when a person becomes aware of the cognitive issues). They may also act abnormally, such as obsessing over specific topics or objects.
3. Short-term memory loss is extremely common. People may forget a conversation or repeat a question they had asked only moments before. As the condition progresses, long-term memories may fade, and people may forget familiar faces or significant life events. This is one of the most distressing symptoms for loved ones.
4. A person may often be confused or disoriented about time or their environment. They may not recognize where they are, even in a familiar place, potentially getting lost.
5. Aphasia is a condition that occurs when the brain’s language centers are damaged. It affects a person’s ability to use and understand language.
6. Finally, as a person’s ability to function declines, they will gradually need more and more help performing tasks (such as cooking, eating, or any kind of self-care, including brushing their teeth or bathing).

Causes of Reversible and Irreversible Cognitive Disorders

There are several complex causes for reversible and irreversible types of neurocognitive disorders. So, we will examine each separately.

Reversible Disorder Causes

The table below lists underlying issues that can be treated and potentially reversed for full or partial recovery. ^[3]

Category	Examples	Description
Drug Toxicity	Antidepressants, painkillers, antihistamines	Some medications can affect memory and thinking.
Metabolic Issues	Electrolyte disturbances, dehydration, renal failure, hepatic failure, hyperlipidemia, hypoxemia, Wilson’s disease	Metabolic imbalances can impact brain function.
Normal Pressure Hydrocephalus	Head injuries, bleeding in the brain, subdural hematomas, idiopathic (no known cause)	A buildup of cerebrospinal fluid in the brain can cause cognitive symptoms.
Mass Lesions	Tumor, chronic subdural hematoma	Brain abnormalities that may impact cognitive function
Infections	Chronic meningitis, Lyme disease, neurosyphilis, Whipple disease	Infections can cause temporary memory problems
Collagen-Vascular	Lupus, temporal arteritis, rheumatoid vasculitis, sarcoidosis	Autoimmune conditions affecting the brain
Endocrine Disorders	Thyroid disease, parathyroid disease, adrenal disease	Hormonal imbalances can affect cognitive function
Nutritional Deficiencies	Vitamin B12 deficiency, folate deficiency, malnourishment from chronic alcoholism	Poor nutrition can cause confusion and memory loss
Psychiatric Conditions	Pseudodementia	Depression or other conditions that mimic dementia
Miscellaneous	Sleep apnea, chronic obstructive pulmonary disease (COPD), heart failure	Other health conditions that can affect cognition

Causes of Irreversible Disorders

To date, there is no single cause for major neurocognitive disorders; rather, several contributing risk factors exist. One key element is genetics. Many genes are connected to dementia, including an estimated 6% to 28% increase in risk in specific alleles, like APOE ε4. ^[6]

However, these disorders can still occur in a person with no familial history. Regardless of whether someone has a familial (inherited) or sporadic (non-inherited) form of neurodegenerative disease, the underlying disease processes are quite similar. ^[6]

So, to understand the causes, we must first understand the biological processes that occur as we age.

Essentially, different parts of the brain age at different rates, meaning some neuroanatomical pathways (connections between different brain regions) are more vulnerable to degeneration than others.

As these pathways deteriorate, the brain starts producing abnormal proteins. These proteins (like beta-amyloid in Alzheimer’s disease or alpha-synuclein in Parkinson’s disease) are key players in neurodegeneration.

Once these proteins form, they spread along specific anatomical pathways, moving through brain circuits and progressively affecting more regions.

A study in the Journal of Folia Neuropathologica discusses how neurodegenerative diseases are caused by more than just natural changes in the brain. ^[7] It proposes that neurodegenerative diseases result from a cumulative lifetime interaction of genetic and environmental factors, contributing to an individual’s allostatic load (the wear and tear on the body and brain due to stress and other factors).

This means that while these harmful proteins build up naturally as the brain ages (and there is a genetic risk factor), environmental and lifestyle choices also significantly contribute to the process. A higher allostatic load accelerates brain aging and selectively weakens specific neural pathways.

What Contributes to Allostatic Load?

• Chronic stress, including physical and mental stress
• Poor diet, smoking, drinking, and physical inactivity
• Adverse childhood experiences, such as abuse or maltreatment

A healthy lifestyle and good stress management, as well as support and therapy for early childhood trauma, may play significant roles in avoiding cognitive decline over time.

Treatment for Reversible and Irreversible Cognitive Disorders

Treating a cognitive disorder that causes symptoms like memory loss or confusion hinges on having the correct diagnosis. Not all are reversible, but most can be managed. Remember, a healthy lifestyle, therapy for traumatic experiences, and stress management techniques go a long way in preventing these issues.

Let’s go over some common treatments:

1. Nutritional support is the first line of defense. Taking vitamin B12 can help, as can a healthy and complete diet. Diets rich in antioxidants also support brain health. Other supplements, like MCT oil, also show promising results for Alzheimer’s disease. ^[8]
2. Discontinuing or changing medications that may be causing issues can improve symptoms. Remember, never stop using any form of chronic medication without speaking to a doctor first about a plan to taper off safely, especially in the case of medications like benzodiazepines.
3. Speak to your doctor about testing for any underlying health problems, such as hypothyroidism or infections, that could be interfering with cognitive functioning.
4. Investing in therapy for conditions like depression could help improve reversible cognitive impairment (often referred to as pseudodementia). Therapy is also a good way to reduce your allostatic load and manage stress, helping to protect your brain from dementia long term.
5. While there is no cure for conditions like Alzheimer’s disease or vascular dementia, medications such as cholinesterase inhibitors (e.g., donepezil) may help manage symptoms and delay progression.
6. Structured activities, consistent routines, and therapy modalities can help a person with an irreversible cognitive condition preserve their quality of life and feel safe.

For advanced cases, palliative care focuses on comfort and quality of life rather than curative treatments. During this time, it is critical that family and loved ones receive support through therapy and counseling.

Conclusion

Losing control of one’s mind is a terrifying prospect. It’s equally difficult for family members to watch loved ones “slip away.” Luckily, many cognitive disorders are partially reversible, especially with prompt treatment.

Steady advances are also being made in treating those cognitive disorders that cannot be reversed. Perhaps the most important takeaway for all of us is that a committed effort to reduce our allostatic load through nutrition, exercise, stress management, and trauma reduction can go a long way toward maintaining brain health later in life.