Personality Changes May Help Detect Form of Dementia

A simple personality test could help doctors more quickly detect dementia with Lewy bodies, a form of dementia often confused with Alzheimer’s disease, according to a study led by researchers at Washington University School of Medicine in St. Louis.

Dementia with Lewy bodies is the second most common neurodegenerative cause of dementia. It shares many characteristics with both Alzheimer’s and Parkinson’s disease. Getting the correct diagnosis is important because some medications used to treat the mental health symptoms of Alzheimer’s disease can be potentially dangerous for people with dementia with Lewy bodies. “Patients with Lewy body dementia often have hallucinations and other behavioural problems, so they’re frequently treated with antipsychotic drugs early in the course of their illness,” says lead author James Galvin, M.D., assistant professor of neurology. “However, some types of antipsychotic drugs may put them at risk of serious side effects, so it’s important for physicians to be able to quickly determine who has Lewy body dementia.” Such side effects include neuroleptic malignant syndrome, a condition where muscles become rigid and the body’s ability to regulate its own heat production breaks down. This can lead to renal failure and death. The study appears in the May 29 issue of Neurology, the scientific journal of the American Academy of Neurology. In Alzheimer’s disease, a protein known as amyloid accumulates in the brain. Amyloid is also often found in the brain in patients with Lewy body dementias, but the key diagnostic indicator is the presence of aggregates of the protein alpha-synuclein in brain cells. These clumps are called Lewy bodies. Lewy body dementia can cause fainting, hallucinations, Parkinson’s-like symptoms such as tremor, rigidity and motor impairment, intermittent alterations in attention and awareness, and memory loss. The study involved 290 people who were part of a larger study and were tested every year for an average of about five years. By the end of the study, 128 of the participants had confirmed cases of dementia with Lewy bodies, 128 had Alzheimer’s and 34 had no form of dementia. Researchers followed the participants through death, including autopsy results. During annual interviews, participants or their family members were asked about changes in personality, interests and drives. Even prior to diagnosis, researchers more often found passive personality changes in people with dementia with Lewy bodies than people with Alzheimer’s. Such changes included diminished emotional response, disinterest in hobbies, repetitive behaviours, and growing apathy, or lack of interest. People with dementia with Lewy bodies were two times more likely to have passive personality traits at the time of the first evaluation than people with Alzheimer’s disease. By the time of death, up to 75 percent of those with dementia with Lewy bodies had passive personality changes compared to 45 percent of those with Alzheimer’s disease. “Currently we mainly look for memory problems and other cognitive problems to detect dementia, but personality changes can often occur several years before the cognitive problems,” says Galvin. “Identifying the earliest features of dementia may enable doctors to begin therapy as soon as possible. This will become increasingly important as newer, potentially disease-modifying medications are developed. It also gives the patient and family members more time to plan for the progressive decline.” Galvin said more detailed personality tests are not often used in most office settings because of time and lack of training. “Our results show incorporating a brief, simple inventory of personality traits may help improve the detection of dementia with Lewy bodies,” said Galvin. (Source: Neurology : Washington University in St Louis : July 2007)