Dementia may take 3.5 years to diagnose after symptoms begin, but why?

• Dementia is a hard disease to diagnose for a number of reasons.
• A new study has found that people who have dementia are, on average, diagnosed 3.5 years after symptoms first appear.
• This is even longer — an average of 4.1 years after symptoms first show — for people with early onset dementia.

According to the World Health Organization (WHO), about 57 million people around the world…