Mixed dementia is a condition in which Alzheimer's disease and vascular dementia occur at the same time. Many experts believe mixed dementia occurs more often than was previously realized and that it becomes increasingly common in advanced age. This belief is based on brain autopsies showing up to 45 percent of people with dementia have signs of both Alzheimer's and vascular disease.

The concept of mixed dementia is clinically important because the combination of the two diseases may have a greater impact on the brain than either by itself.

Symptoms

• May follow a pattern similar to either Alzheimer’s or vascular dementia or a combination of the two.

• Some experts recommend suspecting mixed dementia whenever a person has both evidence of cardiovascular disease and dementia symptoms that get worse slowly.

Treatment

• As with vascular dementia, lifelong attention to risk factors and overall health of the heart and blood vessels could play a key role in preventing mixed dementia. These measures might also help delay or prevent progression of symptoms in older adults.

• Since most of the drugs approved to treat Alzheimer’s disease have also shown a similar benefit in treating vascular dementia, there is reason to believe they may also be of some help in mixed dementia. Two of the drugs galantamine (Razadyne) and rivastigmine (Exelon) have been tested and shown to offer modest benefit specifically in mixed dementia.

• No drugs are currently approved by the FDA to treat mixed dementia.