Study Reveals Early Symptoms and Prevalence of Lesser-Known Alzheimer’s Variant
In a shocking discovery, researchers have found that a lesser-known variant of Alzheimer’s disease, called posterior cortical atrophy (PCA), begins with problems affecting vision rather than memory. This revelation came to light through the first large-scale international study of the condition, led by researchers at the University of California at San Francisco. The study, published in the journal Lancet Neurology, analyzed records of 1,092 PCA patients from 16 countries and revealed that the syndrome typically starts affecting patients at age 59, about five to six years earlier than the more common form of Alzheimer’s.
The early symptoms of PCA often go unnoticed or misdiagnosed, leading to delayed diagnosis and treatment. Patients with PCA may experience difficulties reading, driving, and understanding complex scenes. For example, they may struggle to navigate through a grocery store to find a specific item. These visual impairments often lead patients to seek help from optometrists and ophthalmologists before being referred to neurologists.
The study also found that PCA patients have levels of harmful amyloid and tau plaques in their brains that are similar to those seen in the more common form of Alzheimer’s. However, these plaques are found in different regions of the brain that are involved in vision, such as the occipital and parietal lobes.
Although the number of patients with PCA has not been established, researchers estimate that it may account for up to 10 percent of all Alzheimer’s cases. This would mean that there are potentially close to 700,000 Americans living with this lesser-known variant. However, due to the unusual symptoms and lack of awareness, many individuals may go undiagnosed for years.
“We have a lot of work to do to raise awareness about the syndrome,” said Gil D. Rabinovici, one of the study’s authors and director of the UCSF Alzheimer’s Disease Research Center. “One thing that we found in our large study is that by the time people are diagnosed, they’ve had [the disease] for quite a few years.”
The delayed diagnosis of PCA is partly due to the lack of understanding and recognition of the condition. It was first described in medical literature in 1988, but it took nearly three decades for experts to agree on a formal description in 2017. The condition gained some public attention when British author Terry Pratchett announced his diagnosis in 2007 and pledged to donate $1 million to Alzheimer’s research.
The new study on PCA is considered groundbreaking as it sheds light on the diagnosis, biological markers, and demographics of patients with this variant. Carolyn Fredericks, an assistant professor of neurology at Yale School of Medicine, called the study “important” and emphasized that PCA is an area of Alzheimer’s research that has been understudied.
With greater awareness of PCA, doctors may be able to diagnose it earlier, leading to timely interventions and treatments. Additionally, researchers can now include PCA patients in future Alzheimer’s clinical trials, which were previously excluding individuals with visual symptoms.
While there is currently no cure for PCA, patients can benefit from occupational therapy and visual impairment services. Simple lifestyle changes, such as reading large-print books and using better lighting, can also improve their quality of life. Some patients may find relief from treatments that improve Alzheimer’s symptoms or slow down the progression of the disease.
For individuals like Charlie Stewart, who was diagnosed with PCA after struggling with vision problems during a game of dominoes, life has changed significantly. Charlie’s wife, Susan Stewart, initially thought his difficulties were due to a vision problem. However, they were shocked to learn that it was a sign of PCA. Charlie’s symptoms have worsened over the years, with occasional memory problems and frustration.
Despite the challenges, Charlie remains active both physically and mentally. He loves gardening, takes long walks in the San Pablo Bay National Wildlife Refuge, and enjoys reading and solving puzzles. He also participates in a clinical study, receiving injections of a gene-modifying drug that may reduce harmful tau protein levels.
Charlie’s positive outlook on life is reflected in his writings about his experiences with PCA for his local newspaper. He aims to uplift others by sharing his journey and focusing on the brighter side of things.
The study on PCA has opened doors for further research and understanding of this lesser-known variant of Alzheimer’s. With increased awareness and inclusion in clinical trials, there is hope for earlier diagnosis, improved treatments, and ultimately, a better quality of life for those living with PCA.
