VASCULAR DEMENTIA

The second most common cause of dementia is related to changes in the cardio-vascular system (heart and blood vessels). When something happens to the blood supply to the brain, parts of the brain can be damaged. Following a heart attack, for example, the heart may stop pumping for a time before the patient is revived. During this time, the brain is deprived of oxygen and this can sometimes result in dementia. More common and more gradual is Multi-infarct Dementia. This results from a series of often small strokes which damage parts of the brain. Small areas of the brain die as a result of clots or bleeding from the small blood vessels which supply blood to those areas. When tissue dies it is called an infarct - hence the name multi-infarct dementia. Once the brain tissue is damaged in this way it doesn't recover. The tendency to stroke can be related to lifestyle. This type of dementia is usually associated with atherosclerosis (hardening of the arteries) and high blood pressure. Risk behaviours include poor diet with high levels of fat and salt, excess consumption of alcohol and smoking. If high blood pressure is detected and treated early, the risk of dementia occurring may be reduced. Changes of lifestyle which address the risk factors can help also reduce the likelihood of Multi-infarct Dementia.

Multi-infarct demetia accounts for approximately 20% of all dementias. Many people with dementia have a mixture of Multi-infarct Dementia and AlzheimerÕs Disease.

DEPRESSION

Sometimes people suffering severe depression can present with symptoms of dementia. Such people may respond to anti-depressants. It is worthwhile discussing this as a course of action to try during the process of diagnosis. Depression is also common amongst those with Alzheimer's Disease and often ant-depressants assist in controlling this particular aspect of the disease.

INFECTIONS

Some infections can produce a sudden onset of a confusional state and this may not last. However, some infectious diseases have dementia as one of the symptoms that develop as the disease progresses. These include HIV/AIDS, Syphilis, Chronic Meningitis, Encephalitis, Creudzfeldt-Jakob Disease. Doctors may test for the presence of such diseases where there are indicators. This may be part of a process of elimination.

METABOLIC DISTURBANCES

Sometimes chemical imbalances in the body can result in symptoms of dementia. Such imbalances can be the result of dehydration or nutritional deficiencies. Deficiencies of the B group vitamins and folate can produce cognitive impairment. Certain medical problems including kidney or liver failure or pancreatic disorders can result in electrolyte or blood sugar imbalances which provoke a confusional state, changes in sleep, appetite or emotions. Sometimes certain glands whose task is to release hormones involved in chemical balance in the body fail to function properly. Malfunction of the thyroid, parathyroid and (very rarely) adrenal glands can cause confusion which mimics dementia. Certain chemicals can also act as toxins or induce reactions in some people. This can include alcohol and medications, as well as the more rare events of carbon monoxide or heavy metal poisoning. Even certain prescription drugs can cause adverse reactions in some with confusion and symptoms of dementia being the result. Sedatives, hypnotics, neuroleptics, antihypertensives and antiarthritic medications are among the most common. All medications, including over-the-counter remedies, should be monitored by a doctor to reduce the possibility of side effects. Doctors will use blood tests to identify levels of chemicals in the blood including hormone levels as part of the diagnostic process.

NON-DEGENERATIVE BRAIN INJURY

A number of things can happen to put pressure on the brain that can cause cognitive impairment or symptoms of dementia. Many can be treated and the symptoms reversed. These include

• Brain Tumours - Benign tumours can be surgically removed; for other tumours, a combination of surgery and radiation/chemotherapy can help the patient.
• Subdural Haematoma (blood clot on the surface of the brain) - Clots can form which create collections of fluid that exert pressure on the brain. These clots can be treated by draining the fluid before it has caused permanent damage.
• Normal Pressure Hydrocephalus - The flow and absorption of spinal fluid, which is manufactured inside the brain, is interrupted. When the fluid is not absorbed properly, it builds up inside the brain and creates pressure. Surgery can be performed to drain the spinal fluid into the bloodstream to relieve the pressure.
• Head Trauma - Traumatic brain injury can occur at any age. Trauma from a fall or an accident can precipitate personality, cognitive or behaviour changes. If brain injury is mild, previous functioning may be restored over time. In cases of moderate to severe head trauma, brain impairment may be lasting. Careful attention should be paid to any blows to the head. Head injuries should be examined by a neurologist or rehabilitation specialist.