By Maureen Salamon
THURSDAY, Aug. 27, 2015 (HealthDay News) -- Severe liver damage may be four times more common among Americans with the liver infection hepatitis C than previously believed, a new study suggests.
Analyzing nearly 9,800 patients with hepatitis C, researchers learned that using a biopsy alone to reveal liver cirrhosis -- indicating scarring in the organ -- is likely to seriously underestimate its prevalence.
The recent emergence of medications that can cure hepatitis C, a "silent killer" that often goes undetected until advanced disease sets in years later, adds weight to the new findings, doctors said.
"We thought it would be important to provide the health care community with some estimate as to the severity of liver disease among patients with hepatitis C because it's a question that comes up very frequently: Just how sick is this community?" said study author Dr. Stuart Gordon, director of hepatology at Henry Ford Hospital in Detroit.
Hepatitis C is a viral infection that's typically spread through contact with the blood of an infected person, and is estimated to kill 500,000 people worldwide each year, according to the World Health Organization. About 2.7 million Americans are thought to have chronic hepatitis C, which when untreated can lead to cirrhosis and liver failure or liver cancer, according to the U.S. Centers for Disease Control and Prevention.
For the study, Gordon and his team analyzed records from 9,783 hepatitis C patients cared for at four large U.S. health care systems. The records indicated that 29 percent of the patients had evidence of liver damage, or cirrhosis. But medical records didn't indicate the cirrhosis in 62 percent of these patients, the study found.
Liver biopsy is considered the gold standard for diagnosing cirrhosis, but the researchers found a fourfold higher prevalence of cirrhosis among patients than shown by biopsy alone. Other clinical tests, including blood tests and a noninvasive scoring system known as the FIB-4 score, can also reveal cirrhosis but are underused, Gordon said.
"There are several messages in our paper, and one is that if you're simply relying on liver biopsy to establish a diagnosis of liver cirrhosis, you're going to be greatly underestimating the prevalence," he said. "One has to be suspect and try to search for that diagnosis any way you can."
Another liver disease expert agreed with this assertion.
"For a long time we've recognized that there are limitations to what has been our gold standard in diagnosing cirrhosis. But looking at one piece from one area of the liver doesn't necessarily reflect what is going on everywhere in the liver," said Dr. Andrea Cox, associate professor of medicine and oncology at the Johns Hopkins Infectious Disease Center for Viral Hepatitis in Baltimore.
"This [new study] is confirmation of the benefit in having multiple ways in assessing the state of someone's liver," added Cox, who wasn't involved in the new research.
The study findings were published this month in The American Journal of Gastroenterology.
With the emergence of new medications that can cure hepatitis C -- which previously had been treatable but incurable -- it's even more important that those infected know their status and seek care before the virus causes advanced liver disease or cancer, experts said. But the main obstacle to widespread use of the drugs is their enormous cost.
Last year, the U.S. Food and Drug approved several treatments for hepatitis C. One, known by the brand name Harvoni, can cure 90 percent of patients with hepatitis C type 1, the most common form, after 12 weeks of use. But Harvoni costs more than $94,000 for a full course of treatment and some health insurers have said they will only cover the cost of the drug for the sickest patients.
"Clearly we want to prevent patients from entering into the stage of cirrhosis, which is essentially a premalignant state where you have to be screened for liver cancer for the rest of your life," said Gordon, explaining why treating hepatitis C is crucial.
In response to the high cost of hepatitis C drugs, a panel of health care experts has recommended that federal and state Medicaid programs expand access to these prescription medications, The New York Times reported Wednesday.
Restrictions on the drugs imposed by many states are inconsistent with sound medical practice, according to the experts from the Public Health Service and President Obama's Advisory Council on HIV/AIDS.
While states can get discounts, the prices of the drugs are still more than $600 a pill.
The panel did not suggest how wider access to the drugs should be funded. But, it did say Medicaid and other public programs should reveal the prices they paid, and also said manufacturers should have to disclose the costs of developing and making the drugs, the Times reported.
Gordon said his research wasn't intended to emphasize the need for treatment, but to emphasize the severity of liver damage among hepatitis C patients.
Despite the high cost of treatment, Cox said, it's cost-effective for those with advanced liver disease whose health care costs are already climbing. Preventing hepatitis C infection is vital, she added, and scientists are developing an effective vaccine for the infection.
"This study highlights that we have effective measures for detecting liver disease," she said, "and they need to be widely implemented."