Home / Treatments And Diseases / Causes of Dementia

Causes of Dementia

Dementia is a clinical syndrome not a disease. The American Heritage Dictionary defines dementia as, “Deterioration of intellectual faculties, such as memory, concentration, and judgment, resulting from an organic disease or a disorder of the brain. It is sometimes accompanied by emotional disturbance and personality changes.”(1)

Some tests used to diagnose dementia are:

1. MRI – magnetic resonance imaging 2. blood tests 3. EEG – electroencephalogram is a graphical record of electrical activity of the brain 4. test spinal fluid – checking the cerebrospinal fluid with a lumbar puncture or spinal tap 5. PET scan – positron emission tomography to check for abnormal molecular cell activity 6. SPECT scan – Single Photon Emission Computed Tomography (nuclear imaging test that shows how blood flows to tissues and organs) 7. observation of recent changes in behavior and memory

Even if all tests come back normal that does not necessarily rule out a degenerative disease factor like dementia. An autopsy of brain tissue is the only way to get a conclusive answer.

There are over 50 conditions that cause dementia. Alzheimer’s disease is considered the primary cause. Alzheimer’s disease is named after Dr. Alois Alzheimer who in 1906 described two symptoms of the disease; plaques of tiny dense deposits throughout the brain which become toxic at excessive levels and tangles which interfere with vital processes destroying the living cells. As brain cells die the brain begins to atrophy or shrink.

Vascular Dementia is the second largest cause of dementia. It is caused by brain cells being deprived of oxygen. It is also referred to as multi-infarct (multiple strokes) dementia because it is caused by a re-occurrence of strokes.

Other diseases that cause dementia are a group of diseases referred to as frontotemporal dementia. Frontotemporal dementia commonly referred to as FTD affects different sections of the brain than Alzheimer’s or vascular dementia. The frontal and temporal lobes see the most changes. The initial changes are more in the area of behavior and language as opposed to memory changes. Some other names for variations of frontotemporal dementia are:

1. Pick’s Disease. – Pick bodies and cells contain an abnormal form of a protein called tau. 2. Semantic Dementia 3. Frontal Lobe Dementia 4. Primary Progressive Aphasia 5. Corticobasal Degeneration – nerve cell loss and atrophy of multiple areas of the brain including the cerebral cortex and the basal ganglia.

Another form of dementia is Lewy body dementia which was named after Fredrick Lewy the man who first described the abnormal protein in 1912. It is caused by abnormal deposits of protein called alpha-synuclein. This protein forms inside the nerve cells of the brain. It accounts for less than a quarter of the dementias. Lewy body is also known as:

1. Diffuse Lewy body disease 2. Cortical Lewy body disease 3. Lewy body disease 4. Senile Dementia of Lewy type 5. Dementia with Lewy bodies 6. Lewy body variant of Alzheimer’s disease

Drug induced dementia should always be considered when dealing with the elderly. They are especially sensitive to medications either prescribed or purchased over the counter. An imbalance in vitamins, either too large a dose or too little, could also cause dementia type reactions in the elderly.

Other causes of dementia can be:

1. Frontal Lobe Meningioma – a benign tumor. 2. Tuberculous meningitis is a chronic infection. 3. Head injuries can damage the brain. 4. Subdural hematoma is a swelling on the brain. 5. Brain tumors can lead to dementia. 6. Sleeping pills can cause temporary memory lapses that present as dementia. 7. Binswanger’s disease (BD) is subcortical vascular dementia. 8. High blood pressure if left untreated can lead to dementia. 9. Amyotrophic lateral sclerosis is a neurological disease that also has some dementia changes. 10. Syphilis (sexually transmitted disease) in the late stages of the disease can end in dementia. 11. Progressive supra nuclear palsy is gait and balance disorder. 12. Steel Richardson syndrome causes nerve cell destruction, lack of coordination, stiffness, eye movement problems, and mild dementia. 13. CJD (Creutzfeldt Jakob) or mad cow disease (bovine spongiform encephalopathy) forms rapidly and is often fatal. It is caused by abnormal prions in the brain. 14. Alcohol especially combined with poor nutrition is another risk factor for dementia. Alcohol depletes the B vitamins. Korsakff’s syndrome is brought on by heavy and prolonged alcohol consumption. It causes a deficiency in thiamin (B1) which affects the brain and nervous system. 15. Depression if left unchecked can become severe and cause symptoms similar to Alzheimer’s disease. 16. Vitamin B12 deficiency can cause changes in the brain. 17. Heavy-metal poisoning can cause changes in the brain. This form of dementia may be reversed if you can catch it early enough. 18. HIV Human immunodeficiency virus may break down brain cells and then release a damaging enzyme which then attacks neurons causing dementia symptoms. 19. Meningitis is infection of the tough layer of tissue that surrounds the brain and spinal cord. 20. Encephalitis is a virus that causes irritation and swelling of the brain. 21. Diabetes damages blood vessels which can lead to vascular dementia. 22. Kidney failure disrupts the balance of salts and other chemicals in the blood and if left untreated could lead to brain damage and dementia 23. Liver disease – hepatic encephalopathy occurs when toxic substances build up faster than they can be removed by the liver. The toxins seep into the blood and then get into the brain causing dementia. 24. Thyroid disorders, hyperthyroidism and hypothyroidism, if not controlled will eventually lead to mental illness and dementia 25. Lyme disease can end in dementia. 26. Multiple sclerosis dementia can be involved very late in the disease process.

There are many other lesser known causes of dementia. This list should give you many options to explore in finding the cause of dementia in the people you know as you remember dementia is not a disease, but a symptom of many possible diseases.

dementia. (n.d.). The American Heritage Dictionary of the English Language, Fourth Edition. Retrieved February 06, 2009, from Dictionary.com website: http://dictionary.reference.com/browse/dementia