Abnormal liver tests are common in elderly people, new research shows.

Researchers from the University of Nottingham in the United Kingdom studied 13,276 patients over the age of 75 for seven years, according to the August issue of Alimentary Pharmacology and Therapeutics. They found that one in six had at least one abnormal liver test which increased the risk of cancer and other diseases, such as diabetes, heart attacks, respiratory disease and dementia.

However, there was a marked difference in mortality for those with one abnormal test reading and those with more than one.

The researchers found that higher levels of asparate transaminase increased the risk of death by only 1.8%, while elevated levels of alkaline phosphatase raised it by 1%. Abnormal bilirubin was linked with a 15% increase.

However, those patients that had two or more abnormal tests were twice as likely to die from cancer and 17 times more likely to die from liver disease than those with normal tests.

Other research has shown that livers in older people have a reduced regenerative capacity and take longer to respond to viral and toxic threats, according to Medscape.com. Liver diseases such as cirrhosis, a scarring of liver tissue caused by alcohol abuse, viruses and other factors, are more common among the elderly and can result in healthy liver tissue being replaced with fatty lesions or "fibrotic or tumorous tissue." Liver diseases can also affect how drugs are metabolized.

A new study in Gastroenterology notes that bacterial infections are common in people with cirrhosis and can increase mortality.