Of the 36 million people around the world who are estimated to have dementia (including Alzheimer's disease), as many as 28 million of them -- or 75 percent -- have not actually been diagnosed, according to a new global report.
In wealthy countries, 20 to 50 percent of dementia cases are diagnosed. And in middle-income and poor countries, the number diagnosed is as low as 10 percent, according to report by the Alzheimer's Disease International, which is a network of 76 Alzheimer's disease associations. However, the report also said that most people who have early stage dementia do want to be informed of their diagnosis.
"Failure to diagnose Alzheimer’s in a timely manner represents a tragic missed opportunity to improve the quality of life for millions of people," Alzheimer's Disease International chairman Dr. Daisy Acosta said in a statement.
The report also emphasized the importance of diagnosing and treating Alzheimer's disease early, since there are some drugs and interventions that are most effective when taken in the early stages of the disease.
Researchers increasingly believe that many drugs being tested for Alzheimer's have been tried on people who are already too far gone. Earlier diagnosis will help countries develop infrastructure for treating people in the earliest stages of the disease, when drugs have the most chance of doing some good.
In the report, early interventions include taking acetylcholinesterase inhibitors and undergoing cognitive stimulation.
There is also some research to suggest taking gingko biloba and having caregivers who are properly trained, educated and supported are also able to help, though their effect "has not been specifically quantified," the report said.
In the United States, Alzheimer's disease is the No. 6 leading cause of death, with deaths from the disease rising by 66 percent from 2000 to 2008, according to the nonprofit Alzheimer's Association. There are about 5.4 million people in the U.S. with Alzheimer's.
Dementia is usually nonreversible, and affects the way people think, speak, behave and remember things. The first sign of the disease is forgetfulness, and manifests as mild cognitive impairment (worse than typical forgetfulness, but is not yet full-blown dementia), according to the National Institutes of Health.
A recent study in the journal Neurology showed that small, surprising factors could, together, take a big toll on dementia risk. These factors include eyesight quality, problems with bladder control, dental issues and improper fit of dentures, along with the more obvious factors like diabetes and heart disease.