Around 10 percent of Alzheimer’s patients were reported to have a condition that could impact activities such as driving and writing in a recent study
Scientists have issued a warning as a lesser-known sign of dementia could appear while driving. This potentially dangerous symptom is found to occur in 10 percent of those with Alzheimer’s disease.
Many of us are aware of the most common signs of dementia. A syndrome that leads to progressive deterioration of the brain, some of the earliest symptoms include memory loss and behavioural changes.
However, there are some lesser known signs. A recent study revealed that a condition known as posterior cortical atrophy (PCA) was found in one in 10 patients with Alzheimer’s disease, one of the most prevalent types of dementia.
PCA is a constellation of visuospatial symptoms that present as the first symptoms of Alzheimer’s disease. One of the study’s authors, Marianne Chapleau, said that unlike memory issues, patients with PCA struggle with judging distances, distinguishing between moving and stationary objects and completing tasks like writing and retrieving a dropped item despite a normal eye exam.
The organisation Rare Dementia Support notes that this can cause “difficulties” when driving “quite early on”. People are also more likely to become lost when driving or walking as a result.
As part of the study, which was conducted by UC San Francisco, the team analysed data from more than 1,000 patients in 16 countries. They discovered that PCA “overwhelmingly predicts” Alzheimer’s.
Some 94 percent of the PCA patients had Alzheimer’s pathology and the remaining six percent had conditions like Lewy body disease and frontotemporal lobar degeneration, Science Daily reports. In contrast, other studies show that 70 percent of patients with memory loss have Alzheimer’s pathology.
Among the affected participants 61 percent demonstrated an inability to copy or construct basic diagrams or figures; 49 percent had difficulties identifying the location of something they saw; and 48 percent had an inability to visually perceive more than one object at a time. Moreover, 47 percent faced new challenges with basic math calculations and 43 percent with reading.
Study authors said better tools and training are needed to identify patients with PCA. “We need more awareness of PCA so that it can be flagged by clinicians,” said Chapleau. “Most patients see their optometrist when they start experiencing visual symptoms and may be referred to an ophthalmologist who may also fail to recognize PCA.
“We need better tools in clinical settings to identify these patients early on and get them treatment.” The average age of symptom onset of PCA is 59, several years younger than that of typical Alzheimer’s. This is another reason why patients with PCA are less likely to be diagnosed, Chapleau added.
Senior author Gil Rabinovici, director of the UCSF Alzheimer’s Disease Research Centre, added that better understanding of PCA is “crucial for advancing both patient care and for understanding the processes that drive Alzheimer’s disease.”
He said: “It’s critical that doctors learn to recognize the syndrome so patients can receive the correct diagnosis, counselling and care. From a scientific point of view, we really need to understand why Alzheimer’s is specifically targeting visual rather than memory areas of the brain. Our study found that 60 percent of patients with PCA were women – better understanding of why they appear to be more susceptible is one important area of future research.”
The Alzheimer’s Society warns: “As dementia gets worse, it affects these skills even more. This means everyone with dementia will eventually be unable to drive safely. How quickly this happens varies from person to person.
“Most drivers with Alzheimer’s disease will need to stop driving in the middle stage of dementia. Some types of dementia have certain early symptoms that mean an end to driving might be sooner. For example, visual hallucinations are common in dementia with Lewy bodies and impulsive behaviour is common in frontotemporal dementia.”
If you or someone you know displays any symptoms of dementia you should speak to a doctor.