How does aging affect memory and cognition (thinking)?

Almost all of us become aware of changes in memory and cognition (thinking) as we get older. We begin to have difficulty recalling names of people and places, notice that our mental processing has slowed, and that learning is more difficult. We find that certain functions (for example, eye-hand coordination) are also slower.

How common are dementia and Alzheimer's disease?

It is generally acknowledged that dementia doubles in frequency every 5 years from the age of 65. Estimates suggest that 5% of adults over age 65 have dementia and as high as 50% for those over age 85. Of those who have dementia, from 50% to 75% are thought to suffer from Alzheimer's disease.

Dementia — and particularly Alzheimer's disease — represent very significant public health problems, since the percentage of the population in this age group is rapidly increasing. It is currently estimated that some 4.5 million adults suffer from Alzheimer's disease and by the year 2030, this number may easily double or triple. Current estimates of the total cost for health care to this segment of the United States population come close to 100 billion dollars annually.

When should memory loss become a concern?

This question is difficult because memory loss can be influenced by many factors. A temporary cognitive decline can be caused by:

  • Changes in a person's physical health, including a chronic disease that is worsening
  • Certain medications
  • Use of substances
  • Changes in electrolytes
  • Changes in kidney, liver, and thyroid function

In addition, psychosocial issues — such as stress or loss of friends or loved ones — can lead to depression, which may affect thinking and functioning. In the absence of these factors, if changes in memory and thinking are noted and are occurring more frequently than in the past, they could be a concern.