Visual Perception Changes May Be Early Warning Sign of Alzheimer’s Disease, Especially in Women: Study
Memory loss is often associated with Alzheimer’s disease, but a recent study suggests that changes in visual perception abilities may actually be an early warning sign, particularly in women. The research focused on individuals with posterior cortical atrophy (PCA), a condition characterized by shrunken tissue in brain regions responsible for interpreting and reacting to visual information. While their cognitive abilities may appear normal, these individuals may experience difficulties with depth perception while driving or reading, especially at night.
The study, published in the Lancet Neurology journal, analyzed data from nearly 1,100 people with PCA. Autopsies revealed that 94 percent of them had signs of Alzheimer’s disease, indicating that PCA is closely linked to Alzheimer’s. Interestingly, PCA is diagnosed at an average age of 59, which is five or six years earlier than the average age of Alzheimer’s diagnosis. Furthermore, women make up 60 percent of PCA cases, making it more prevalent among females.
Although individuals with PCA may initially have normal cognitive function, it typically takes around four years for them to receive a diagnosis. By this time, they often have mild to moderate dementia, including deficits in memory, executive function, behavior, and speech. Unfortunately, many people are unaware that they have PCA or that it can serve as an early warning sign of Alzheimer’s disease. Marianne Chapleau, the lead study author and a neuropsychologist at the University of California in San Francisco, emphasizes that individuals often attribute visual problems to aging eyesight rather than connecting them to dementia. This lack of awareness prevents them from seeking earlier intervention.
The study found that 61 percent of participants had “constructional dyspraxia,” an inability to copy simple diagrams or figures, at the time of their PCA diagnosis. Additionally, approximately half of them struggled with identifying the locations of objects they saw and perceiving multiple objects simultaneously. These symptoms, although indicative of PCA, are often not immediately associated with Alzheimer’s disease. Andrew Budson, a neurology professor at Boston University, explains that individuals typically consult optometrists and ophthalmologists before realizing that the problem lies in the brain. Only then are they referred to a neurologist.
Even after a neurology consultation, a PCA diagnosis may not be immediately reached. Further tests, such as magnetic resonance imaging (MRI) scans to detect brain shrinkage patterns consistent with PCA, are often necessary. A consultation with a dementia or memory disorders expert may also be required. However, receiving a PCA diagnosis as early as possible is crucial because there are steps individuals can take to manage symptoms. Treatment with anti-amyloid medicines like lecanemab (Leqembi) may slow the progression of symptoms, as PCA is typically caused by Alzheimer’s disease. While more research is needed, these Alzheimer’s drugs may one day be able to detect and prevent the worsening of PCA at its earliest stages.
While there is no specific way to prevent or cure PCA, adopting a healthy lifestyle can still have benefits. Regular exercise, a balanced diet, and engaging in cognitive activities contribute to overall brain health. Once diagnosed, managing symptoms and slowing the progression of dementia can be supported through interventions such as cognitive therapies, medications, and individualized care plans.
In conclusion, visual perception changes may serve as an early warning sign of Alzheimer’s disease, particularly in women. Individuals with PCA often experience difficulties with depth perception and object recognition, which are initially attributed to aging eyesight. However, these symptoms may indicate the presence of Alzheimer’s disease. Early diagnosis is crucial for managing symptoms and potentially slowing the progression of dementia. While there is currently no cure for PCA, adopting a healthy lifestyle and seeking appropriate interventions can contribute to overall brain health and improve quality of life for those affected.
