Atypical Forms of Dementia Are Being Diagnosed More Often in People in Their 50s and 60s

The Washington Post reports that a growing number of people are being diagnosed with atypical forms of dementia in midlife, including behavioral variant frontotemporal dementia, primary progressive aphasia, posterior cortical atrophy, Lewy body dementia, and early-onset Alzheimer's in people with no family history. These diseases manifest in people in their 50s and 60s, sometimes even earlier and sometimes a bit later, and possess some of the same underlying pathology seen in people with typical Alzheimer's — amyloid plaque and tau tangles in the brain. According to the U.S. National Institute on Aging, early-onset dementia cases represent about 5 percent of the total number of Alzheimer's patients. Efforts to understand the pathology include the Longitudinal Early-Onset Alzheimer's Disease Study enrolling 500 cognitively-impaired people between 40 and 64 with early-onset dementia caused by Alzheimer's. The researchers are conducting annual clinical and cognitive assessments, imaging, biomarker, and genetic studies. Their goal is to define patients and characterize their symptoms and rate of disease progression, then enroll them into clinical trials. "No one knows why these diseases start in specific regions of the brain but we think it is influenced by the normal organization of brain networks," said Massachusetts General Hospital's Bradford Dickerson. "These circuits talk to one another. There is a shared vulnerability to these disease pathologies."