More than one in ten people diagnosed with dementia may have a common, treatable liver disease that causes similar symptoms, experts say.
This means that thousands of people may have been wrongly told they have an incurable disease that robs them of their memory, when in fact their problems are reversible, they add.
A study of more than 68,000 people diagnosed with dementia found that nearly 13 percent showed signs of brain “poisoning,” known as hepatic encephalopathy (HE).
This is caused by cirrhosis of the liver, when scar tissue builds up in the organ, usually as a result of excessive alcohol consumption, obesity, or hepatitis viral infection.
The new findings support research published in February that showed about 10 percent of U.S. veterans with dementia may in fact have HD.
Speaking to MailOnline, Dr Rob Howard, professor of old age psychiatry at University College London, said: “No one should be diagnosed with dementia without physical causes of their confusion being ruled out.”
Early symptoms of hepatic encephalopathy include confusion, forgetfulness, personality or mood changes, changes in sleep patterns, and difficulty writing, which are also symptoms of dementia.
However, British dementia specialists cast doubt on this suggestion, saying there are in fact subtle differences between HD and dementia that doctors could spot.
Cirrhosis of the liver affects around 18 per cent of men and 11 per cent of women in the UK and causes fatigue, nausea, swelling of the limbs and itchy skin.
Because scarring prevents the liver from filtering toxins from the blood as it should, they build up and can affect the brain, causing hepatic encephalopathy.
Early symptoms include confusion, forgetfulness, personality or mood changes, changes in sleep patterns and difficulty writing, which are also symptoms of dementia.
As it progresses, it may also cause unusual or slow movements, shaky hands and arms, extreme anxiety and severe confusion, slurred or slurred speech, and seizures.
However, unlike dementia, which only gets worse over time, hepatic encephalopathy can be completely reversed with proper treatment.
This includes specific antibiotics and nutritional supplements.
Study author, Virginia-based gastroenterologist Dr Jasmohan Bajaj, said: ‘We need to raise awareness that cirrhosis and related brain complications are common, silent, but treatable when detected.
‘As the population ages, the possibility of overlap between hepatic encephalopathy and dementia has increased and should be taken into account.’
He added: “Undiagnosed cirrhosis and potential hepatic encephalopathy may be a treatable cause or contribute to cognitive decline in patients diagnosed with dementia.”
Liver cirrhosis also increases the risk of liver cancer, which is another important reason why it should be detected, Dr. Baja said.
In the study, he and his colleagues analyzed data from 72 health care providers on 68,807 patients, mostly in their 70s, who were diagnosed with dementia between 2009 and 2019.
None of them had previously been diagnosed with cirrhosis. The team analyzed the results of blood tests to determine the levels of certain compounds to calculate the fibrosis score 4 (or FIB-4), a common test for detecting cirrhosis.
Commenting on the research for Medscape Medical NewsDr. Nancy Reau, a liver specialist at Rush University Medical Center in Chicago, said doctors may not realize that liver disease leads to cognitive decline.
‘Using simple tools such as FIB-4 can ensure that liver disease is not overlooked as a contributing factor in a patient presenting with neurocognitive symptoms.’
However, speaking to MailOnline, Dr Rob Howard, professor of old age psychiatry at University College London, said: ‘Full-blown hepatic encephalopathy looks different to dementia.
‘The symptoms of hepatic encephalopathy fluctuate in a way that Alzheimer’s does not and anyone who works in a memory clinic will be familiar with that.
‘No one should be diagnosed with dementia without ruling out physical causes for their confusion.
‘Simple tests, including a liver function test, should always be performed.
“But I don’t think it’s credible to say that people with dementia have been misdiagnosed, based on this evidence.”