COGNITIVE DISTURBANCES AND COGNITIVE PROBLEMS - NEUROPSYCHOLOGY - 2024

The cognitive disorders and cognitive problems, including mild cognitive impairment, are considered an intermediate stage between normal or expected cognitive impairment due to aging and the development of a more serious decline, dementia (Mayo Clinic, 2012).

Mild impairment of cognitive functions may involve deficits in memory, language, impaired judgment or thinking. Both the person and their relatives may begin to notice these changes; however, they do not reach a level of severity sufficient to interfere with routine activities or daily life (Mayo Clinic, 2012).

Cognitive problems can vary from an almost barely perceptible presence to a more significant presence, sometimes cognitive abilities will progressively decrease, while in other people they may remain stable for years (Memory and Aging Center University of California, 2016).

In recent decades, the study of cognitive functions related to age and different pathologies has become a central point, both for the medical and neuropsychological areas, due in large part to the increase in the longevity of the population.

Recently, the medical community has changed its perspective on memory loss in the elderly population. Previously, memory alterations were considered as an inevitable event that was presented in a consequent way with the progressive increase of age (Institute of Cognitive Neurology, 2016).

It is currently known that there are multiple factors that will protect our memory capacity even at very advanced ages and that therefore, cognitive impairment in a mild stage can be considered pathological or indicative of a demential process rather than an evolutionary event (Institute of Cognitive Neurology, 2016).

What is mild cognitive impairment (MCI)?

People with mild cognitive impairment may suffer from various more significant or severe memory, language, or executive function disorders than expected for their age, without these symptoms interfering with their daily lives (National Institute on Aging, 2016).

Some of the most common symptoms in mild cognitive impairment are difficulties remembering people's names, losing the thread of a conversation or a significant tendency to lose things (Alzheimer's Australia, 2016).

Normally, people with mild cognitive impairment are able to carry out all the activities of their daily life with varying degrees of efficiency. They often try to compensate for their memory deficits with some external system, such as diaries, notes or calendars (Alzheimer's Australia, 2016).

Mild cognitive impairment is not a type of dementia. In many cases the alterations can remain stable; however, they are more likely to worsen leading to dementia (Alzheimer's Society, 2015)

How many people have mild cognitive impairment (MCI)?

Different investigations estimate that between 5-20% of people over 65 years of age present mild cognitive impairment (Alzheimer's Society, 2015).

On the other hand, 10-15% of people with a diagnosis of mild cognitive impairment have a high probability of developing Alzheimer's dementia compared to 1-2% of healthy subjects in the same age range (Sánchez-Rodríguez, 2011).

What are the symptoms of mild cognitive impairment (MCI)?

It is not surprising that as age increases, episodes of forgetfulness occur, it takes more time to find an answer or to carry out a task. But it is possible that when these situations persist, they may indicate the presence of mild cognitive impairment (MCI) (Mayo Clinic, 2012).

Some of the following situations may be experienced (Mayo Clinic, 2012):

• Frequent forgetfulness.
• Forgetting important events such as appointments or commitments.
• Losing the thread of conversations, movies, books or your own thinking.
• Difficulty in making decisions, planning and / or interpreting instructions.
• Difficulty recognizing frequent or familiar paths.
• Increased impulsivity or reduced judgment.
• Both the individual and those close to him can be aware of these types of changes.

Symptoms depending on the cognitive area

Experts usually classify symptoms according to the cognitive area that is affected or altered (Alzheimer's association, 2016):

Mild amnesic cognitive impairment

It mainly affects memory. The person may begin to show significant forgetfulness such as appointments, conversations, events that he normally remembered easily (Alzheimer's association, 2016). Furthermore, this type can be classified as:

• Single domain amnesic MCI: symptoms are related only to memory (Sánchez-Rodríguez and Torrellas-Morales, 2011).
• Amnesic MCI with involvement in multiple areas: the symptoms are mainly memory-related, but complaints occur in other areas (Sánchez-Rodríguez and Torrellas-Morales, 2011).
• Non-amnesic mild cognitive impairment: the patient does not report memory complaints, it fundamentally affects the ability to make decisions, anticipate the time or the sequence of steps necessary to perform a task, among others (Alzheimer's association, 2016). It can also be a single domain or affect multiple areas (Sánchez-Rodríguez and Torrellas-Morales, 2011).

In general, alterations will occur in the following areas (Alzheimer's Society, 2015):

• Memory: forgetting recent events, appointments, names, or a recent question.
• Reasoning: difficulty in planning, problem solving or loss of train of thought.
• Attention: Difficulty maintaining attention and focus, easy distraction.
• Language: it usually takes more time to find the right words in the construction of an answer.
• Visual perception: difficulty interpreting distances, depths or walking down stairs.

Although normally healthy people begin to experience some signs of a decrease or minimal alteration of cognitive functions with age, all these symptoms will present in a more serious way than in normal aging (Alzheimer's Society, 2015).

It is common that with increasing age pauses are needed to recall data or words; however, getting disoriented and getting lost in familiar places or forgetting family names can be indicative of mild impairment (Alzheimer's Society, 2015).

What are the diagnostic criteria for cognitive impairment (MCI)?

Currently there is no specific diagnostic test that indicates the presence or absence of mild cognitive impairment (Mayo Clinic, 2012).

The specialist will make a clinical diagnosis based on the information obtained both from the patient himself and his relatives and from the application of some tests (Mayo Clinic, 2012).

Complaints in relation to the memory area are usually present from the beginning of the symptoms of mild cognitive impairment. They can be manifested both by the patient and by people close to him.

In addition, it is common for them to describe other symptoms, difficulty finding the correct words when speaking, loss of objects, disorientation in different environments, loss of continuity of thought, conversations and / or daily activities (Sánchez-Rodríguez and Torrellas-Morales, 2011).

In most cases, the following considerations are taken into account (Mayo Clinic, 2012):

• Memory and other cognitive function deficits: planning, following instructions, making decisions.
• Medical history shows that the person has a decreased cognitive level in relation to the ideal or expected.
• Generalized mental function and activities of daily living are not significantly affected, although symptoms may cause concern and / or discomfort.
• The use of standardized neuropsychological tests shows a level of cognitive functioning that is mild but below that expected for their age and educational level.
• The signs and symptoms are not severe enough to consider the presence of dementia.

Various proposals have been made regarding the essential diagnostic criteria for the diagnosis of mild cognitive impairment, some of them are the following (Sánchez-Rodríguez and Torrellas-Morales, 2011):

Diagnostic criteria of the Spanish Society of Neurology for the diagnosis of mild cognitive impairment

1. Alteration of one or more of the following cognitive areas: attention / executive function, language, memory, visuopespatial area.
2. This alteration must be: acquired; referred by the patient or by a reliable informant; of months or years of duration; objectified in the neurological examination; the disturbance does not interfere or interfere minimally with normal activities; there is no disorder of consciousness or cold neurobehavioral syndrome and / or dementia.

Criteria of the Mayo Clinic for amnestic mild cognitive impairment

1. Subjective symptoms of memory loss corroborated by valid report.
2. The patient or the informant report a decline in one or more cognitive domains in relation to previous abilities during the last 12 months.
3. Significant evidence of mild or moderate impairment in memory and other cognitive functions.
4. Activities of daily living remain without significant alterations.
5. This situation cannot be explained by dementia and another medical cause.

Diagnostic criteria according to the International Psychogeriatric Association-World Health Organization

1. No age restriction.
2. Decrease in cognitive ability stated by the patient or informant.
3. Gradual decrease with a minimum duration of six months.
4. Any of the following areas may be affected: memory / learning, attention / concentration, thinking, language and / or visuospatial function.
5. Decrease in mental state assessment scores or neuropsychological tests one standard deviation below the value of the control group.
6. There are no systemic, cerebral or psychiatric processes that can explain the clinical picture.

What are the causes of mild cognitive impairment (MCI)?

No single specific cause for mild cognitive impairment has been identified.

Current scientific evidence shows that mild cognitive impairment can sometimes show some brain changes similar to those found in some types of dementia (Mayo Clinic, 2012).

These changes include (Mayo Clinic, 2012):

• Abnormal levels of beta-amylode plaques and proteins characteristic of Alzheimer's disease.
• Presence of Lewy bodies, associated with Parkinson's disease, Lewy dementia, and some cases of Alzheimer's.
• Small strokes or reduced blood flow in some areas of the brain.
• Reduction of the total volume of the hippocampus.
• Enlargement or dilation of the cerebral ventricles.
• Reduction of glucose metabolism in some brain regions.

Are there risk factors that increase the likelihood of mild cognitive impairment (MCI)?

In general, the factors most related to the suffering of mild cognitive impairment are the same as those identified in dementia (Alzheimer's association, 2016):

• Advanced age
• Family history of Alzheimer's and other dementia.
• Medical conditions that increase the risk of suffering from cardiovascular or cerebrovascular diseases.

On the other hand, the Mayo Clinic (2012) also highlights other risk factors:

• Present a specific form of a gene called APOE4, related to Alzheimer's.
• Diabetes.
• Depression.
• Hypertension.
• High cholesterol.
• Consumption of alcohol and tobacco.
• Absence of physical exercise.
• Absence of social or cognitively stimulating activities.

Is there a treatment for mild cognitive impairment (MCI)?

With regard to drugs, there is currently no specific treatment for mild cognitive impairment. Despite this, there are a wide variety of clinical and experimental studies underway that try to investigate the effectiveness of different drugs: cholinesterase inhibitors - used in Alzheimer's disease -, non-steroidal anti-inflammatory drugs or statins (Alzheimer's Australia, 2016).

Apart from this, there is solid scientific evidence on the benefits of neuropsychological rehabilitation and cognitive training. Constantly working on attention, memory, executive function and the rest of the cognitive functions will be essential to achieve the stability of the progress of the symptoms and on the other hand to develop compensatory strategies that provide people with useful and efficient tools to compensate their deficits.

On the other hand, maintaining a healthy diet, exercising regularly, and maintaining optimal health by avoiding the consumption of harmful substances or controlling possible risk factors are variables that can influence the development of symptoms and progression of mild cognitive impairment.

Conclusions

Mild cognitive impairment is a clinical condition that can cause significant alterations in the cognitive sphere of people, in addition to causing notable discomfort in their day to day life.

Despite this, an essential distinguishing feature with dementias is that these deficits will or will not significantly alter both routine activities and daily life of the patient.

An early diagnosis is essential since the early use of cognitive intervention will provide the individual with better compensation strategies for their symptoms of alterations. They must also be monitored to detect more significant changes that indicate the development of an insane process.

References

1. Alzheimer's Association. (2016). Mild Cognitive Impairment. Obtained from Alzheimer's Association: alz.org
2. Alzheimer's Australia. (2016). Mild Cognitive Impairment. Obtained from Alzheimer's Australia: fightdementia.org
3. INECO. (2016). Cognitive Impairment. Obtained from the Institute of Cognitive Neurology: ineco.org.ar
4. Mayo Clinic. (2012). Mild cognitive impairment (MCI). Obtained from Mayo Clinic: mayoclinic.org
5. NIH. (2016). Mild Cognitive Impairment. Retrieved from National Institute on Aging: nia.nih.gov
6. Sánchez-Rodríguez, J., & Torrellas-Morales, C. (2011). Review of the construct or mild cognitive impairment: general aspects. Rev Neurol, 52 (5), 300-305.
7. Society, Alzheimer's. (2015). What is mild Cognitive impairment (MCI)? Obtained from Alzheimer's Society.