Mixed Dementia


Mixed dementia is not a single condition, but the combination of two or more disorders, at least one of which is termed a dementia. There are a number of possible combinations, the most common being the combination of Alzheimer’s disease and vascular dementia. To be considered to have mixed dementia, you must have lost intellectual or cognitive abilities in at least two areas, such as memory, attention, language, presence of mind, and decision-making abilities. You also may have motor and gait impairment, affective disturbances, sleep disturbances, and/or incontinence.

General information

Individuals with mixed dementia experience a gradual, yet relentless, decline in cognitive functioning over a period of many years, approximately a decade. Mixed dementia symptoms vary depending on the types of brain changes involved and the brain regions affected. In many cases, symptoms may be similar to, or even indistinguishable from, those of Alzheimer’s. In other cases, a person’s symptoms may suggest that more than one type of dementia is present. The symptoms of mixed dementia may progress faster, or be manifested earlier, because the brain is affected by more than one type of problem or damaged in more than one area.

Mixed dementia is infrequently diagnosed during life, but many researchers feel the condition deserves more attention because the combination of two or more types of dementia has a greater impact on the brain than one type alone. Evidence suggests that the presence of more than one type of dementia-related brain change may increase the chances a person will develop symptoms.

The treatment for mixed dementia depends on exactly which disorders are combined in the diagnosis. Alzheimer’s disease, which is usually one of the conditions, has no effective treatment or cure. However, a number of different treatments are being used for symptoms suffered by those with mixed dementia, ranging from sedatives and anti-depressants to antioxidants and blood pressure medication.

As with Alzheimer’s disease, a diagnosis of mixed dementia can be confirmed only after a brain autopsy or postmortem examination of the brain. Neuroimaging, i.e., computerized tomography (CT) or magnetic resonance imaging (MRI), is useful in revealing vascular lesions and excluding other causes of dementia, some of which may be treatable. Most individuals whose autopsies showed they had mixed dementia were diagnosed with one specific type of dementia during life — most commonly, Alzheimer’s disease. But, the autopsies of those diagnosed with Alzheimer’s showed that 54 percent had coexisting pathology. The most common coexisting abnormality was previously undetected blood clots or other evidence of vascular disease. Lewy bodies were the second most common coexisting abnormality.

Social Security Administration POMS DI 23022.344 — Mixed Dementia

Mixed dementia meets Social Security Administration Medical Listing 12.02A and B. It also is listed under the Social Security Administration’s (SSA) Compassionate Allowance Program, which was launched in 2008 to expedite certain disability claims.

Applying for disability benefits under the Compassionate Allowance Program requires the same procedure every applicant must follow when applying for SSA disability benefits; however, you will be
notified if your condition is being considered as a compassionate allowance.

Your representative may be able to help expedite your disability claim if you have been diagnosed with mixed dementia.