Two-thirds of people think dementia is a normal part of ageing rather than a medical condition, a survey suggests.

The poll of around 70,000 people across the globe found 95% also believe they could develop dementia in their lifetime.

In the UK, one in four (39%) health workers agreed that doctors and nurses ignore people with dementia, while 67% of the public agreed people with dementia are impulsive and unpredictable.

Jeremy Hughes, chief executive of Alzheimer’s Society, said: “Dementia is not a natural part of ageing, yet someone develops it every three seconds – it is a global health crisis.

“While dementia is affecting more and more people, it’s horrifying to hear that so many who have it are still experiencing terrible stigma as they simply try to get on with their daily lives.

“This is unacceptable and highlights the urgent need for us all to take action.

“To find that so many UK healthcare professionals agree those in their profession are ignoring vulnerable people with dementia and that only half believe competent practitioners exist in this area when they should be their mainstay of support is deeply concerning.”

Around 850,000 people in the UK have a form of dementia.

Dementia is thought to cost the UK economy more than £26 billion each year.