Mild cognitive impairment (MCI) is a transitional stage between normal age-related forgetfulness and dementia. Age-related memory impairment is common after the age of 70 with occasional lapses of memory. Typical examples of this might include misplacing keys or forgetting the name of an old friend whom you haven’t seen for some time. The majority of elderly people do say they are sometimes forgetful and not able to remember as well as they used to.
The difference between age-related forgetfulness and MCI is that, in addition to memory impairment, people with MCI also experience difficulty with language, judgment, and problem solving. According to the American College of Physicians, 20% of the population over the age of 70 has some form of MCI. MCI can also be shown through non-memory related symptoms such as depression, anxiety, and personality changes that reflect a decline from previous level of functioning. Although there are various subtypes of MCI, the most common form is called the amnesic type of MCI. MCI has been extensively studied and it appears that it is a pre-dementia state leading to Alzheimer’s disease (AD) at a rate of about 20% per year. In other words, the majority of patients who have a diagnosis of MCI will likely develop AD within five years. There is a smaller population who develop dementias other that AD and some will remain as MCI. The reason for these variations are not fully understood, but generally thought to be the type and location of the brain damage. Genetic factors as well as the presence or absence of Amyloid plaques are thought to be the initial step in development of AD. MCI has been studied using Pittsburgh compound B (PIB) that detects amyloid plaques in the brain of the patients destined to develop AD. In patients with MCI, the amyloid plaques are present in smaller proportion as compared to the patients with AD.
The cause or causes of MCI are currently unknown; however the risk factors appear to be similar to AD. These include: age, education, genetic susceptibility such as APO-E positivity and co-morbid medical conditions such as strokes, hypertension, heart disease, diabetes and high cholesterol.
There are currently no approved medicines for MCI. However, in a recent study, Aricept did slow the progression of MCI to AD by about 6 months. The effect was short-lived and lasted approximately 18 months. Although there are genetic susceptibilities that play an important role in the development of MCI, one can lower the risk factors with intentional physical activity, mental stimulation, healthy diet habits, and properly treating medical co-morbidities such as hypertension, heart disease, high cholesterol and diabetes.
So what should you do if you suspect that you or a loved one may have MCI? The first step is to recognize the pattern of forgetfulness and determine if this is a recurring issue or just an isolated incident. If you notice a pattern that is also verified by others such as friends or family members, then it is time to ask your doctor and start the process of evaluation. Your doctor will determine if it needs further investigation.
M. Reza Bolouri, MD
Alzheimer’s Memory Center