GPs are failing to spot dementia early enough, leaving patients without access to beneficial treatments, according to the Medical Research Council.
People who are actively screened for dementia in medical studies live longer than those who have been diagnosed with the disease by their family doctors, the researchers found.
In the first study to examine life expectancy after dementia as recorded by GPs, scientists from the Medical Research Council looked at data from more than 350 GP surgeries in the UK between 1990 and 2007.
Researchers found that once diagnosed with dementia by their doctors, patients aged 60 to 69 had an average life expectancy of 6.7 years. A previous MRC study has shown that people in a comparable age range actively screened for dementia as part of a research study have a life expectancy of 10.7 years.
The study also revealed that death rates are more than three times higher in people with dementia in the first year after GP diagnosis than in those without the condition.
Scientists also discovered that GPs were recording dementia in a non specific way and were not differentiating between Alzheimer’s disease and vascular dementia - which could affect the types of long term treatments people receive and how their disease is managed.
The latest research was based on records from more than 135,000 people aged 60 and over.
Dr Greta Rait, who led the study, published online in the British Medical Journal, said: “Our findings will help clinicians to make more realistic estimates of life expectancy for patients when they are diagnosed and also assist policymakers in planning services.”