Medical professionals identify unusual visual symptoms as a distinctive indicator of Alzheimer's disease

Alzheimer's disease, often associated with memory loss and confusion, reveals a lesser-known yet significant early warning sign – visual problems. Some individuals exhibit difficulties in judging distances, distinguishing between moving and stationary objects, and face challenges in writing. Unfortunately, these symptoms may go undiagnosed for years, especially if individuals only consult their eye doctors, as not all providers are aware of this association.

To raise awareness, the University of California San Francisco conducted the first large-scale international study on this phenomenon, known as posterior cortical atrophy (PCA).

Examining the medical records of over 1,000 PCA patients from 16 countries, the study revealed that visual-spatial symptoms of PCA manifest about five or six years earlier than those with the more common form of Alzheimer’s.

Although the exact number of people with PCA is not firmly established, researchers estimate that this variant may account for up to 10 percent of Alzheimer’s cases, suggesting that approximately 700,000 Americans could be affected.

PCA is a specific subtype of Alzheimer’s disease, and not all Alzheimer’s patients will experience these symptoms.

The visual-spatial challenges may include difficulty with reading and math, using everyday objects, judging distances, and recognizing faces. As the disease progresses, memory problems may become more apparent.

The typical age for the onset of symptoms is 59 years old, six years before the average age for diagnosing Alzheimer’s disease. Importantly, these symptoms can affect individuals with no other memory issues, leading some to believe the problems are not neurological. Many attribute worsening vision to the aging process and may not seek medical care, opting for glasses instead.

On average, it takes just under four years from experiencing atypical visual symptoms to receiving a diagnosis.

To improve early identification, researchers emphasize the need for increased awareness among clinicians, optometrists, and ophthalmologists.

Recognizing PCA early can facilitate timely intervention and appropriate treatment. While there is currently no cure, PCA patients may benefit from participating in clinical trials for medications in development or exploring FDA-approved anti-amyloid drugs.

Understanding PCA is crucial for advancing patient care and gaining insights into the processes driving Alzheimer's disease.

The study underscores the importance of recognizing this syndrome to provide correct diagnoses, counseling, and care.

Future research should delve into why Alzheimer's targets visual areas of the brain, and understanding the apparent higher susceptibility of women, who make up 60% of PCA patients.

The research was published in the Lancet Neurology journal.