What is mild cognitive impairment?

Mild cognitive impairment is a step before suffering from dementia, with memory loss being the central pillar collapsing in those affected.

After many years of research in this regard, mild cognitive impairment is defined as the intermediate state between a normal mental situation and dementia, emphasizing memory impairment as the primary function affected.

It is known that aging per se leads to a progressive loss or dysfunction of neurological functions, visual, auditory, language, and memory, especially for recent events (episodic memory), not for long-term memory, which stores practically unlimited. It is estimated that the brain loses around 2% in volume and weight for every decade that passes. But aging would not fully explain this situation since a high percentage of the elderly do not present criteria for mild cognitive impairment.

It should be noted that a series of requirements or criteria must be met to recognize that someone suffers from mild cognitive impairment:

  • Memory impairment, preferably described by one of the family members.
  • Have the rest of the cognitive functions preserved?
  • Not present a substantial impairment of the basic abilities of daily life.
  • There are no criteria for dementia.
  • Practically, three types of mild cognitive impairment are known, which would be:
  • The amnesic form (with a clear and exclusive impairment of memory).
  • The diffuse form (affecting other areas such as visual, auditory, or communicative, with or without memory impairment).
  • The non-amnesic focal form (individual involvement of a function such as a language, without memory impairment). The latter, as it does not affect memory, is not recognized by all experts.

As we said, this entity is an intermediate state, in such a way that there is an annual progression of more than 10% towards dementia (mainly in the form of Alzheimer’s ) compared to people of the same age who do not suffer from it, so this situation confers a higher risk of eventually suffering from it.

Although the prevalence of mild cognitive impairment has varied over the years according to the criteria used, it is currently estimated at around 18-20%, four times higher than Alzheimer’s disease. There are no significant differences between men and women.

Causes of mild cognitive impairment

Aging is not the only cause of this situation since not all the elderly show signs of mild cognitive impairment. There are, therefore, a series of factors that are pointed out as possible reasons or causes for suffering from this problem:

  • Genetic factors: research has been carried out over the years that have revealed the relationship with a series of proteins and genes whose function is altered in this pathology. Among the most studied, the apolipoprotein E-epsilon 4 stands out. Its presence is vital for the transition from mild cognitive impairment to dementia.
  • Cardiovascular risk factors: the presence of diabetes, arterial hypertension, and its consequences at the level of the cerebral blood vessels are essential for the development of this pathology.
  • According to many theories, life habits: mild cognitive impairment is associated with pathological situations such as obesity and alcohol abuse due to the toxicity of some substances that would directly affect the proper functioning of the brain.

Sociodemographic factors: although it is not universally accepted, numerous scientific works reflect a higher incidence of cognitive impairment in people with a lower educational and social level, either because their mental reserve is lower or because their health care for years has been worse and, therefore, less protective against external factors harmful to the cognitive state.