Vascular cognitive impairment

GENERAL ASPECTS

What is vascular cognitive impairment?

It is the term used to designate all those cognitive symptoms (memory impairment, orientation, executive functions, language…) that appear as a consequence of the presence of a significant cerebrovascular disease. These symptoms may be of sufficient magnitude to cause dementia (vascular dementia).

What is its frequency?

It is one of the most frequent causes of dementia. Along with dementia with Lewy bodiesit represents the second or third most frequent cause, only behind Alzheimer’s disease.

What type of cerebrovascular disease can produce it?

The presence of vascular cognitive impairment is basically recognized in two situations. On the one hand, when cognitive impairment appears shortly after having suffered a clinical stroke (ischemic or hemorrhagic). On the other hand, when, in the absence of a clinical stroke, extensive cerebral vascular lesions (“small vessel disease”) are observed in a person with cognitive impairment on CT or brain MRI.

Can all strokes cause cognitive impairment?

Some studies suggest that approximately 10% of stroke patients develop dementia one to four years later. However, the risk differs depending on the brain region affected by the stroke. For example, strokes affecting the frontal lobes, language areas, thalamus or right temporal lobe have been associated with an increased risk of cognitive impairment.

What is small vessel disease?

This is the term used to refer to brain lesions produced by the inadequate functioning of small cerebral blood vessels. The malfunction of these vessels can produce small cerebral infarcts (lacunar infarcts) and lesions of the white matter, which are seen in neuroimaging tests (MRI or CT).

What are the factors that increase the risk of developing vascular cognitive impairment?

The same ones that increase the risk of stroke and small vessel disease. These are the so-called “vascular risk factors”. The most relevant is arterial hypertension. However, diabetes mellitus, high cholesterol levels, sedentary lifestyle, obesity, coronary heart disease, atrial fibrillation and smoking, among others, also play an important role.

CLINIC

What are the symptoms of vascular cognitive impairment?

The symptoms identified are usually heterogeneous, and virtually any type of cognitive deficit can be present. However, a global slowing in the speed of reasoning and attention failures are common. However, and especially in those cases that appear after having suffered a clinical stroke, the symptoms depend on the brain region that has been affected (for example, a stroke affecting the posterior cerebral artery may produce memory deficits).

What is the evolution of the symptoms like?

The evolution is variable. Sometimes deficits are identified that remain stable over time. Other times the symptoms worsen progressively, as a consequence of the extension of the small vessel disease. On other occasions there is an abrupt worsening as a consequence of the appearance of new strokes with clinical repercussions.

DIAGNOSIS

How is vascular cognitive impairment diagnosed?

It is usually diagnosed by a combination of a characteristic clinical history and neuroimaging tests such as CT or cranial MRI. These tests make it possible to determine the extent of cerebral vascular lesions and to identify any sequelae that may have resulted from a stroke.

What is observed when analyzing the brains of patients with vascular cognitive impairment?

It is very common that, in addition to the lesions produced by the alteration of cerebral vascular flow, lesions compatible with other neurodegenerative diseases, especially Alzheimer’s disease, are also identified. This is probably due to the fact that alteration of the cerebral vasculature is also a risk factor for the development of neurodegenerative diseases. This combination of several degenerative and nondegenerative pathologies in a patient with cognitive impairment is known as “mixed dementia”.

TREATMENT

Can it be prevented?

The strategy to prevent the development and progression of vascular cognitive impairment is based on the control of the vascular risk factors listed above. In this way, it is possible to limit the onset and progression of cerebrovascular disease.

Is the use of antiplatelet agents recommended in patients with vascular cognitive impairment without a history of clinical stroke?

The use of antiplatelet agents, such as aspirin or clopidogrel, in patients who have never presented symptoms compatible with a stroke is a matter of debate. If prescribed, it should be done on an individualized basis, analyzing the personalized risk of suffering a stroke in the future. Nor is it clear that it reduces the progression of small vessel disease or cognitive impairment.

Is the use of antiplatelet agents or anticoagulants recommended in patients with vascular cognitive impairment with a history of clinical stroke?

In this scenario, their use is indicated as part of the strategy to prevent new episodes of stroke. The use of antiplatelet agents or anticoagulants will depend on the cause of the stroke.

What other drugs can be used?

In those cases in which the course is progressive, drugs similar to those used in Alzheimer’s disease, such as acetylcholinesterase inhibitors (donepezil, rivastigmine and galantamine) or memantine, can be used.

What other strategies can be used for the management of patients with vascular cognitive impairment?

Non-pharmacological measures common to other dementias are also useful in this case: caregiver education, falls prevention, home help, cognitive stimulation therapies and social support management, among others.