The vascular dementia (VD) may be defined as memory impairment that occurs with dysfunction in one or more of the following cognitive domains: language, praxis, executive function, orientation, etc. It is severe enough to affect the patient’s daily activities.
This type of disorder appears as a result of brain damage due to multiple vascular accidents or focal lesions in the blood vessels supplying the blood to the brain (National Institute of Neurological Disorders and Stroke, 2015).
Vascular dementia is the second leading cause of dementia in Western countries, following Alzheimer’s disease. In addition, it is a potentially preventable type of dementia (Álvarez-Daúco et al., 2005).
Typically, vascular dementia and vascular cognitive impairment arising as a result of various risk factors for both this pathology as for the condition of stroke , these include atria fibrillation , hypertension , diabetes , high cholesterol and / or antipathy amyloidal , among others ( National Institute of Neurological Disorders and Stroke, 2015).
Statistics of vascular dementia
After Alzheimer’s disease (AD), vascular dementia is the second leading cause of dementia.
Different statistical studies have shown that the incidence of vascular dementia (DV) in Europe was approximately 16/1000 at age 65 and 54/1000 at 90 years, making up about 20% of all cases of dementia (Bernal and Roman, 2011).
In the United States an estimated 4 million people have dementia symptoms and it has been predicted that this figure could reach 16 million people due to population aging, in which between 20-25% of the cases (approximately 3, 5 million people) will present dementia of vascular origin (Bernal and Roman, 2011).
The age of onset of this disorder is between 50-59 years in approximately 45% of cases, while 39% is between 60 and 69 years of age (Ramos-Estébanez et al., 2000).
This fact is mainly due to the increase in the prevalence in these age ranges of two or more chronic diseases such as hypertension, diabetes, heart disease or osteoarthritis (Formica et al., 2008).
Regarding gender, vascular dementia is more frequent in men, unlike Alzheimer’s type dementia, which is more frequent in women (Bernal and Roman, 2011).
Although most cases of vascular dementia are usually pure, about 12% of cases present an Alzheimer’s disease component to a greater or lesser extent, increasing the prevalence of vascular dementia by around 35-40% (Bernal and Roman, 2011).
Definition and concept of vascular dementia (DV)
The exponential growth of life expectancy in the last decades has led to an increase in diseases related to aging. Currently, dementia is a major health problem in developed countries, as its incidence continues to increase (Bernal and Roman, 2011).
Under the term vascular dementia (VD), a poorly homogenous group of disorders in which vascular factors play an important role in the development of cognitive impairment (CD ) has been classically included (Álvarez-Daúco et al., 2005).
In the scientific literature regarding the area of vascular dementia, we can find many terms associated with this clinical entity and in many cases some of them are misused as synonyms: among them we can find: multi-infarct dementia, arteriosclerotic dementia , dementia due to leukoaraiosis, Binswaswagner’s disease, vascular cognitive impairment, etc. (Bernal and Roman, 2011).
The vascular dementia is defined as that which results from cerebral vascular lesions, hemorrhagic, ischemic or type hypo / hyper perfusion (Bernal and Roman, 2011).
The different etiological conditions will cause different brain vascular lesions that will vary in number, extension and location affecting both cortical and sub cortical regions, especially cholinergic ones (Bernal and Roman, 2011).
Vascular lesions may damage cortical or sub cortical structures or may be restricted to white matter and basal ganglia, causing damage to specific circuits or disrupting connections between networks that may be essential to support different cognitive and / or behavioral functions (Bernal and Roman, 2011).
Clinical features of vascular dementia
The symptoms and signs of this pathology along with the clinical course can be very variable from one patient to another, depending on the cause of the lesions and especially on the location of these lesions (Jodi Vicente, 2013).
In most cases, the onset of vascular dementia usually presents an abrupt and abrupt onset that follows a phased evolution. Many families observe periods of stabilization, followed by “outbreaks” or more pronounced cognitive losses (Jodi Vicente, 2013).
Usually, the most common complaint from relatives and even the same patient, is “feeling that they are not the same.” It may refer to apathy, depression, Apulia, isolation and social inhibition or changes in personality (Bernal and Roman, 2011).
In addition, it is possible to observe focal type neurological alterations that will affect sensitivity and motor skills. There may be a gait deficit, inability to perform basic activities of daily living (bathing, using the telephone, dressing, going to the bathroom, eating, etc.), clumsiness in language production, etc. In addition, it is also possible to observe incontinence or urinary urgency.
Patients will also present alterations in the cognitive sphere. They may present a decrease in the attention level, a slowing of processing speed, a deficit in the ability to plan and execute actions and activities, confusion, disorientation, and a significant alteration of immediate memory.
Types of Vascular Dementia
There is wide heterogeneity in the classification of types of vascular dementia. However, the review of the body of knowledge about vascular dementias allows differentiating several types:
Cortical vascular dementia or multi-infarction
It occurs as a consequence of multiple focal lesions in the cortical blood vessels. It is usually produced by the presence of emboli, thrombi, cerebral hypo perfusion, or strokes. In most cases, multiple infarcts may be restricted to a cerebral hemisphere, so deficits will be associated with the predominant cognitive functions in the hemisphere (National Institute of Neurological Disorders and Stroke, 2015).
Sub cortical vascular dementia or Binswanger’s disease
It occurs as a consequence of lesions in the blood vessels and nerve fibers that constitute the white matter. The symptoms that are presented are related to an alteration of the sub cortical circuits involved in short-term memory, organization, mood, attention, decision making, or behavior (National Institute of Neurological Disorders and Stroke, 2015).
Different clinical studies, generally post-mortem, have shown cases in which there is a parallel occurrence of both vascular etiologies and Alzheimer’s disease (National Institute of Neurological Disorders and Stroke, 2015).
Diagnosis of vascular dementia
The presence of vascular dementia is determined by the presence of vascular lesions. In addition, it must fulfill the criterion of having no other explainable cause.
Thus, the Neuroepidemiology Branch of the National Institute of Neurological Disorders and Stroke and the International Association for Research and Research in Neurosciences propose that the diagnosis of vascular dementia must be supported under different criteria (Bernal and Roman, 2011):
Features for Probable DV Diagnosis
- Cerebrovascular disease.
- Abrupt or fluctuating progressive deterioration of cognitive functions.
Clinical features consistent with DV diagnosis
- Early presence of alterations in memory.
- History of postural instability falls frequently.
- Early presence of urinary urgency or polyuria not explained by urologic injury.
- Pseudo bulbar palsy.
- Behavioral and personality changes.
Features that make DV diagnosis uncertain
- Early onset of alterations in memory and progressive worsening of this and other cognitive functions in the absence of concordant focal lesions in the neuroimaging.
- Absence of neurological focal signs other than cognitive impairment.
- Absence of cerebrovascular disease in CT or brain MRI.
Causes and risk factors of vascular dementia
The main cause of vascular dementia is stroke. With the term cerebrovascular accident (CVD) we mean any alteration that occurs transiently or permanently in one or several areas of our brain as a consequence of a disorder in the cerebral blood supply (Martinez-Vila et al., 2011).
Further, a stroke may occur as a result of both ischemic processes (refer to the arrival of the blood supply to the brain as a result of a blockage of a blood vessel) and hemorrhagic processes (When blood enters the intra tissue or extra cerebral).
Regarding risk factors, vascular dementia is associated with all factors associated with stroke. Thus, in the first studies on DV, a marked influence of hypertension, heart failure, atria fibrillation , diabetes, smoking, sedentary lifestyle, alcoholism, sleep apnea-hyperpnoea syndromes , hypercholesterolemia, age, low socioeconomic level , etc. (Bernal and Roman, 2011).
On the other hand, it is also possible that patients undergoing high-level surgeries (cardiac, carotid, hip replacements ), with conditions of cerebral hypo perfusion, chronic hypoxemia, exposure to chronic infections or infections, autoimmune diseases and vacuities , are patients with a high risk of presenting DV with cumulative vascular damage (Bernal and Roman, 2011).
Treatment of vascular dementia
There is currently no specific treatment that reverses the damage caused by a stroke. Treatment usually seeks to focus on preventing future stroke by controlling medical risk conditions.
On the other hand, in the therapeutic intervention of the cognitive deterioration will be useful programs of stimulation specific of dementia, like programs destined development and maintenance of concrete cognitive functions.
In addition, multidisciplinary rehabilitation programs combining medical, neuropsychological, occupational, and psychological intervention will also be essential.
The best approach to this type of pathology is to start with the control of risk factors and therefore their prevention. It is essential to wear a style healthy lifestyle, a balanced diet, exercise, avoid alcohol and / or snuff and also maintain a healthy weight.