There are some central symptoms that lead to a diagnosis of Alzheimer’s. These include memory loss, difficulty performing familiar tasks, confusion and poor judgement. But these symptoms may also be features of other conditions and diseases. Depression is a good example and I recall a number of older patients who were admitted to acute psychiatric units I worked on so they could be assessed, correctly diagnosed and treated.
The problem is that some of the signs and symptoms of depression can be similar to dementia. They include someone with a decrease in ability to think or concentrate, confusion, change in appetite and/or weight loss, fatigue or apparent loss of energy, loss of interest in personal hygiene and social activities.
People with Alzheimer’s and people with depression can also be less communicative. They can experience marked changes in their sleep patterns. They can find that they have trouble getting to sleep, or they may wake up very early and not be able to get back to sleep. They may find they are sleeping too much or too little.
Depression can, of course, co-exist with Alzheimer’s. Depression is the second most common psychiatric problem in people with a dementia such as Alzheimer’s. Major depression is associated with some structural changes in areas of the brain. Alzheimer's and the degenerative brain damage it causes may well contribute or be the cause of symptoms.
People with limited power of expression, cognitive problems and confusion may show signs of depression through symptoms such as pain and other bodily complaints, by changes in behavior such as withdrawal, irritability, anger, and preoccupation with dead loved ones.
Depression may also be associated with medical conditions that are common in people with dementia and with some medications. These include antihypertensives (drugs for high blood pressure), antiparkinsonian medications, sedatives and hypnotics, analgesics and hypoglycaemic agents.
I think it is easy to see from everything I have said that informed medical intervention and an accurate diagnosis is central to having the right treatment. Medical treatments for dementia and depression are clearly different. Treatments will depend on diagnosis and dominant symptoms.
Antidepressants can be very effective for people with depression and for people with dementia. Response time is usually 6 to 8 weeks. Different antidepressants may need to be tried before one is found that achieves improvements in their mental state.There are drugs that can help some people with Alzheimer’s, albeit for a limited period of time.
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