What causes memory problems?

Even though Alzheimer’s disease is the cause of significant memory and cognitive problems in more than two-thirds of people 65 or older, there are dozens of other specific causes. (Image: Thinkstock)

Question: If it isn’t Alzheimer’s disease that’s causing my memory loss, what is it?

Answer: Even though Alzheimer’s disease is the cause of significant memory and cognitive problems in more than two-thirds of people 65 or older, there are dozens of other specific causes. It is important for your doctor to determine the most likely cause, because some of these problems will have specific treatments, many have different outcomes, and the genetic implications for other family members will also vary. The following are some examples of the many other causes of dementia besides Alzheimer’s disease.

Cerebrovascular disease

Memory and cognitive problems caused by cerebrovascular disease — disease of the blood vessels, in particular the arteries that supply the brain — including small and large strokes, is the second most cause of dementia and can also co-exist with Alzheimer’s disease. Even in patients who have never had a documented stroke, brain blood vessel blockages and small bleeds can cause dementia that can appear similar to Alzheimer’s disease. This condition is often associated with problems like high blood pressure, diabetes, smoking, obesity, high cholesterol, and heart rhythm irregularities (like atrial fibrillation). Managing these so-called vascular risk-factors becomes an essential part of the management of this cause of dementia.

Dementia with Lewy bodies

Dementia with Lewy bodies (or Lewy Body Dementia) is an illness that presents with symptoms that appear to be a combination of both Alzheimer’s disease (with memory and cognitive difficulties) and Parkinson’s disease (with stiffness, rigidity, shaking or tremor, and walking/balance problems that lead to falls). Some of the other characteristic features of this illness are dramatic fluctuations in behaviour, cognition and function, visual hallucinations (e.g. imagining they see people and animals in the house), and sleep problems (e.g. acting out their dreams while asleep). This illness is important to diagnose because these people are very sensitive to certain medications that are typically used to treat hallucinations (antipsychotics), and they can respond dramatically well to the medications used to treat Alzheimer’s disease. Patients with Parkinson’s disease can also develop memory and other cognitive problems that can complicate this neurological condition.

Frontotemporal dementias

The Frontotemporal dementias are a group of illnesses that often present somewhat differently from the other dementias. One type presents initially with language problems (either difficulty expressing oneself or understanding common words) and another presents with behavioural problems which can range from severe apathy and lack of motivation, to uncharacteristic, disturbing behaviours that appear to lack any inhibitions (e.g. making rude comments or jokes, acting sexually inappropriately, shoplifting etc.). These illnesses often begin at a younger age than Alzheimer’s disease (in the 50s), and can have a significant genetic component.

Medical conditions that cause memory loss

While this list is far from complete, there are some medical conditions that cause memory and cognitive difficulties in older people that can be reversed completely. For example, there are many medications that can cause memory problems (including prescription sleeping pills, and over the counter antihistamines and sleeping aids). Thyroid problems and some nutritional deficiencies can also cause memory problems. And finally, heavy alcohol consumption can lead to dementia.

If you or a family member are worried about memory or cognitive problems, and certainly if they are severe enough to be interfering with your daily function, you should speak to your physician. Do not allow a physician to dismiss your complaint by telling you “What do you expect at your age?” without a careful history, physical exam and formal testing of your memory and cognitive skills.


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