What is the cause of AD?

Scientists are still trying to find the cause of AD. Current knowledge indicates that a progressive loss of brain cells is related to the formation of abnormal ‘plaques’ of insoluble protein fragments in and around the cells. Another characteristic sign of AD is the presence of ‘tangles’ within the brain cells, formed by abnormal twists of tau, a vital protein in healthy cells. Although these formations may be harmless in themselves, they may activate some kind of defence mechanism in the body that causes death of the cells in the affected areas. In fact, it is very likely that AD is not caused by any single factor, but by a number of factors that affect each person differently.

Some cases of early-onset AD may be related to genetic disposition as it often does run in families. However, the vast majority of AD is sporadic with age being the most potent risk factor. After AD, the most common form of dementia is vascular dementia which is caused by a disruption of the supply of blood to the brain, commonly as a result of stroke. Dementia may also be caused by Huntington’s disease, by Parkinson’s disease, by some infectious diseases, and by damage to the brain from physical trauma, metabolic disorders, or toxins.

Although doctors now have a range of ways of determining if patient has AD, the symptoms for the different forms of dementia may be very similar to those of AD. This is why careful attention to symptoms by family members is so important to an accurate diagnosis and early initiation of treatment.