Early detection of Alzheimers can be crucial and people are being warned of a red flag symptom when they drive that could be a symptom of the disease. It has been brought into the public eye following presenter Fiona Phillips announcing that she has been diagnosed with the early onset of the disease.

It is known that the earlier it is diagnosed, the better are the support options for the patient and there are some signs which are to be expected and others that may be surprising, reports the Mirror.

The disease causes slow decline in memory, thinking and reasoning skills and, for motorists, a symptom of the disease is for them having difficulty in remembering the way to a familiar location. But a lesser-known symptom is that people can find it hard to determine colour or contrast which can be noticed when driving.

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“For some people, having vision problems is a sign of Alzheimer's. This may lead to difficulty with balance or trouble reading. They may also have problems judging distance and determining colour or contrast, causing issues with driving,” states the Alzheimer’s Association.

But it added that this should not be confused with vision changing due to cataracts as they get older. But results of a new a survey by the Alzheimer's Society show that not enough people are raising alarm to dementia symptoms.

Just one in three people tell their doctors about themselves or a loved one experiencing dementia symptoms within the first month, with the majority remaining silent. It shows that many people stay quiet because of uncertainties around which symptoms were dementia-like and which were just normal with getting older.

“One in three people (33%) who notice symptoms of dementia in themselves or a loved one keep their fears to themselves for over a month,” the charity said.

According to the survey, which was of 1,100 people, just 15 per cent of people addressed the issue straight away, while 11% said they still haven’t raised their concerns after spotting the first symptom.

But talking is key according to resident doctor on ITV's Lorraine and Good Morning Britain, Dr Amir Khan, who said: “A third of us will go on to develop dementia in our lifetimes – we need to change the idea that getting dementia is inevitable as we age - it’s not called getting old - it’s called getting ill."

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