Experts say more than one in 10 people diagnosed with dementia may have a common, treatable liver disease that causes similar symptoms.
This means thousands of people may have been wrongly told they have an incurable memory-robbing disease, when in fact their condition is reversible, the researchers add.
A study of more than 68,000 people diagnosed with dementia found that around 13% showed signs of brain “poisoning” known as hepatic encephalopathy (HE).
This is caused by cirrhosis, a disease in which scar tissue builds up in the organ, usually as a result of hepatitis caused by excessive alcohol consumption, obesity, or a viral infection.
The new findings support a study published in February that showed that about 10 percent of U.S. veterans with dementia may actually have HE.
Dr Rob Howard, professor of geriatric psychiatry at University College London, told Mail Online: “Dementia should not be diagnosed without ruling out physical causes of confusion.”
Early symptoms of hepatic encephalopathy include confusion, forgetfulness, personality and mood changes, changes in sleep patterns and difficulty writing, which are also symptoms of dementia.
However, UK dementia experts have cast doubt on this theory, saying there are in fact subtle differences between HE and dementia that doctors can notice.
Cirrhosis affects around 18% of men and 11% of women in the UK and causes symptoms such as fatigue, nausea, swelling of the hands and feet and itchy skin.
United States Census Bureau
Scarring prevents the liver from properly filtering toxins from the blood, which can build up and 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 the condition progresses, other symptoms may include abnormal or slow movements, trembling hands or arms, extreme anxiety or severe confusion, slurred speech and seizures.
However, unlike dementia, which worsens over time, hepatic encephalopathy can be fully reversed with proper treatment.
This includes certain antibiotics and dietary supplements.
“We need to raise awareness that cirrhosis of the liver and its associated brain complications are common, asymptomatic, and treatable when detected,” said Dr. Jasmohan Bajaj, a gastroenterologist in Virginia and author of the study.
“With an ageing population, the possibility of overlap between hepatic encephalopathy and dementia is increasing and needs to be taken into consideration.”
He added that “undiagnosed cirrhosis and/or subclinical hepatic encephalopathy may be treatable causes or contributing factors to cognitive impairment in patients diagnosed with dementia.”
Cirrhosis also increases the risk of liver cancer, another important reason to be mindful of it, Dr. Baha said.
A recent report found that around one million people in the UK live with some form of dementia, a number predicted to rise to 1.4 million by 2040.
The Centers for Disease Control and Prevention estimates that 5.8 million Americans currently have Alzheimer’s disease or related dementias, the majority of whom are 65 or older.
In the new study, Dr. Baha and his colleagues analyzed data from 72 US healthcare providers on 68,807 patients, mostly in their early 70s, who were diagnosed with dementia between 2009 and 2019.
None of the participants had been previously diagnosed with cirrhosis. The team looked at the levels of certain compounds in their blood test results and calculated a fibrosis-4 (FIB-4) score, a common test for cirrhosis.
Commenting on the study for Medscape Medical News, Dr. Nancy Lo, a hepatologist at Rush University Medical Center in Chicago, said doctors may not realize that liver disease can lead to cognitive decline.
“Having a simple tool like the FIB-4 can help ensure that liver disease is not overlooked as a cause in patients with neurocognitive symptoms.”
But Dr Rob Howard, professor of geriatric psychiatry at University College London, told Mail Online: “Full-blown hepatic encephalopathy presents differently to dementia.”
“The symptoms of hepatic encephalopathy fluctuate differently than Alzheimer’s disease, but anyone who works in a memory disorders clinic knows that very well.
“Dementia should not be diagnosed until physical causes of confusion have been ruled out.”
“Simple tests should always be done and this includes liver function tests.”
“But I don’t think it’s credible to say, based on this evidence, that people with dementia are being misdiagnosed.”
