Why the cause matters
Alzheimer's disease is the most common cause of dementia, and many other conditions can also affect memory and thinking. Some of them can be treated, and some memory problems improve or resolve once the cause is addressed. Your care team looks for everything that could be contributing, because more than one cause is common.
Medications
Some common medications can affect memory and attention, especially in older adults and when several are taken together. Examples include sleep aids and allergy medicines that contain diphenhydramine, some bladder medications, benzodiazepines used for anxiety or sleep, some pain medications, and some older antidepressants.
Never stop a prescribed medication on your own. Bring a complete list to your appointment, including over-the-counter products and supplements, and ask whether any of them could be affecting your memory.
Vitamin B12 and thyroid
Low vitamin B12 is common in older adults, particularly in people who take metformin or acid-reducing medications for a long time. It can cause memory problems, confusion, and numbness or tingling in the hands and feet. An underactive thyroid can cause slowed thinking, fatigue, and low mood. A simple blood test finds both, and both are treatable.
Sleep apnea
Sleep apnea, in which breathing repeatedly stops and starts during sleep, deprives the brain of restful sleep and oxygen and can affect attention and memory. Loud snoring, gasping at night, and daytime sleepiness are worth mentioning to your doctor. Treatment, often with a CPAP machine, can improve how you feel and think.
Depression and anxiety
Depression can cause trouble concentrating, slowed thinking, and forgetfulness, and in older adults doctors sometimes mistake it for dementia. Depression and early dementia can also occur together. Your provider will likely ask about mood during your evaluation, and treating depression often improves thinking.
Hearing and vision loss
When you struggle to hear, your brain works harder to follow a conversation, and missed information can look like forgetting. Untreated hearing loss is also linked to a higher risk of dementia, so a hearing test is a simple and worthwhile step. The same goes for vision problems such as cataracts.
Other conditions to rule out
- Urinary tract and other infections, which can cause sudden confusion (delirium) in older adults
- Dehydration and low sodium
- Heavy alcohol use
- Normal pressure hydrocephalus, a buildup of fluid in the brain that causes walking problems, bladder control problems, and memory changes, and that can be treated
A sudden change in memory or confusion over hours or days is different from gradual memory loss. Call your doctor the same day or seek urgent care.
If your evaluation does point to Alzheimer's disease, finding it early still matters, because today's treatments work best in the early stages. Read what to expect at a memory evaluation.
This guide is for education and is not medical advice. Treatment decisions are made with your provider after a full evaluation.