I am glad I know that dementia does not have a sudden onset, otherwise I would be worried. I go to a room and stand there wondering what it is I am looking for. Then, I loose my cell phone. While scratching my head with one hand, I realize my phone is in the other. I was going to tell my wife a story the other day about a man I met. I couldn’t remember his name. By the time I gave up on remembering his name, I forgot the story. I want to tell someone about a great actor in a movie. First I can’t remember the actor’s name then I can’t remember the great movie he was in. Oh, I could go on. But, I am glad I know dementia does not have a sudden onset or I would be worried.

I see patients with mild dementia that do suddenly get worse. When this happens, a cause should be sought. For some reason, the elderly and especially the demented do not register and verbalize their bodily sensations. I have seen patients with severe bladder infections present with no symptom other than confusion. As a third year medical student, I saw this for the first time in the psych ward of a local hospital. The lady had been admitted due to worsened mental functioning. We finally got the urine report back and treated her infection. She slowly improved and was able to return home. 

Another common cause of confusion in the elder is electrolyte abnormalities. A low sodium concentration in the blood is the most common. A low sodium can cause confusion, nausea, and abdominal pain. A severely low level can cause seizures. A low sodium is usually the result of medications that cause the kidney to loose sodium in excess to water. Also, the elderly often lower their sodium intake. A low sodium is easily identified by a simple blood test.

Other causes of sudden confusion can be medication, changes in the environment, strokes and disturbances in the sleep pattern. One other word of caution is regarding general anesthesia. I have seen patients who are marginally demented living independently have a severe deterioration after surgery and anesthesia. I warn even mildly demented patients to avoid surgery unless in is absolutely a matter of life and death. 

In summary, if your demented loved one becomes more confused, you should seek out the cause with your doctor. There may be a reason that could be corrected.