With my elders with dementia, it is often not so straightforward. Sometimes the symptom is that the person more is more agitated, aggressive or more lethargic. The person with dementia may not feel well, but not be able to communicate their symptoms. This is serious.
Listen to Dr. Landsverk during a 15 minute interview by Craig Roberts on KFAX Radio. He asked excellent questions, and Dr. Landsverk was able to discuss the many issues involved with elders, and especially those with dementia. Click this link to listen: https://soundcloud.com/lifeline-craig-roberts/10-07-15-hour-2