The damage is the result of the thickening and narrowing (atherosclerosis) of arteries that feed the subcortical areas of the brain. Atherosclerosis (commonly known as “hardening of the arteries”) is a systemic process that affects blood vessels throughout the body. It begins late in the fourth decade of life and increases in severity with age. As the arteries become more and more narrowed, the blood supplied by those arteries decreases and brain tissue dies.
The symptoms associated with BD are related to the disruption of subcortical neural circuits that control executive cognitive functioning:
- Short-term memory
- The regulation of attention
- The ability to act or make decisions
- Appropriate behavior
The most characteristic feature of BD is psychomotor slowness – an increase in the length of time it takes, for example, for the fingers to turn the thought of a letter into the shape of a letter on a piece of paper. Other symptoms include:
- Forgetfulness (but not as severe as the forgetfulness of Alzheimer’s disease)
- Changes in speech
- An unsteady gait
- Clumsiness or frequent falls
- Changes in personality or mood (most likely in the form of apathy, irritability, and depression)
- Urinary symptoms that aren’t caused by urological disease
Brain imaging with CT scans or magnetic resonance imaging (MRI) devices is essential for a positive diagnosis as it reveals the characteristic brain lesions of BD.
BD is a progressive disease; there is no cure. Changes may be sudden or gradual and then progress in a stepwise manner. BD can often coexist with Alzheimer’s disease. Because there is no cure, the best treatment is preventive, early in the adult years, by controlling risk factors such as hypertension, diabetes, and smoking. Behaviors that slow the progression of high blood pressure, diabetes, and atherosclerosis — such as eating a healthy diet and keeping healthy wake/sleep schedules, exercising, and not smoking or drinking too much alcohol — can also slow the progression of BD.
There is no specific course of treatment for BD. Treatment is symptomatic. People with depression or anxiety may require antidepressant medications such as the serotonin-specific reuptake inhibitors (SSRI) sertraline or citalopram. Atypical antipsychotic drugs, such as risperidone and olanzapine, can be useful in individuals with agitation and disruptive behavior. The successful management of hypertension and diabetes can slow the progression of atherosclerosis, and subsequently slow the progress of BD.