Very understandably, almost everyone diagnosed with the hepatitis C virus asks the same question: "What's going to happen to me?"
Unfortunately, with HCV infection, it's very hard for doctors to offer an answer. More than with most diseases, the course of HCV infection varies widely from person to person. In about 15 to 25 percent of people infected with the virus, their immune systems attack the virus and eliminate it, and they never know they were exposed. At the other extreme are people who develop chronic infections and eventually serious liver disease. In between are people who carry the virus but never show signs of trouble, and others who have mild symptoms and some liver damage, but never develop serious illness.
Many factors affect the course of HCV infection
How can one virus act so differently in different people? Researchers don't know all the answers. They do know that men are more likely to develop serious liver problems than women. One study published found that 13 to 46 percent of men developed cirrhosis (scarring of the liver) over a 30-year period of being infected with HCV. Only 1 to 29 percent of women developed the disease during the same period.
The age when infection occurs also makes a difference in the course of the disease. The earlier in life people are infected, the lower the risk of serious complications from hepatitis C infection.
Other health problems and HCV infection
Co-infections with other viruses can worsen the prognosis for HCV. Many people are co-infected with hepatitis C and HIV/AIDS. Both viruses are spread through sharing needles. In a large European study, 33 percent of HIV-positive patients were shown to be infected with HCV as well. When experts looked just at known injection-drug users, they found that 75 percent of HIV-positive patients also had hepatitis C virus. Being infected with these two viruses appears to increase the risk of cirrhosis. In 2008, researchers found that after 20 years of infection, the risk of developing cirrhosis was 21 percent in people who carried both HCV and HIV and 16 percent for those infected only with HCV.
Certain lifestyle aspects also shape the course of HCV infection. People who are infected and who consume alcohol are more likely to develop liver problems than are nondrinkers. Alcoholics are at the highest risk. A study by University of Pennsylvania researchers found that alcohol actually causes the hepatitis C virus to multiply faster. Alcohol also lessens the effectiveness of alpha interferon, which is used to treat serious HCV infections. In one report, Italian researchers showed that alcohol increases oxidative stress in the liver, generating unstable free radicals that can damage liver cells. The scientists speculate that "oxidative injury might be one of the mechanisms by which alcohol contributes to the progression of chronic hepatitis C."
Other researchers have found a connection between hepatitis C infection and type 2 diabetes and obesity. In 2009, scientists from the Center for Liver Diseases at Inova Fairfax Hospital analyzed health data from almost 16,000 people, including some with hepatitis C. According to the study results, obesity and type 2 diabetes were associated with a higher mortality rate in patients with hepatitis C. This finding suggests that making lifestyle changes to ward off obesity and diabetes should be an important consideration for people with hepatitis C.
Surprisingly, the level of virus in the blood, called viral load, doesn't help predict the course of hepatitis C. Some people with high viral levels do well. Others, with low levels of virus, develop liver problems. Doctors use the test to gauge how well treatment is working, but not to make a prognosis. Elevated levels of aminotransferase, a liver enzyme, are a sign that the disease is causing liver damage. But even this marker isn't a perfect predictor. As many as 30 percent of patients with liver damage have normal levels of aminotranferase.
A look at the numbers
When patients ask, "What will happen to me?" the best answer doctors can give is to explain how the disease progresses in an average group of patients. Of every 100 people infected with HCV:
75 to 85 may develop long-term infection; of those:
- 60 to 70 may develop chronic liver disease
- 5 to 20 may develop cirrhosis (scarring of the liver) over a period of 20-30 years
- 1 to 5 are likely to die of the consequences of long-term infection, either from liver cancer or cirrhosis.
As those numbers show, most people infected with hepatitis develop chronic infections. Among them, most have some signs of liver damage. But the numbers are also reassuring. Fewer than 7 percent of those with chronic hepatitis C die of complications from the virus. That means that for a large majority of people, the virus isn't fatal. In many, it causes nothing more than mild symptoms such as fatigue.
The changing picture of HCV infection
There's more good news coming out of clinical trials and pharmaceutical laboratories. The combination treatment used today is more effective than anything doctors were able to offer when the disease emerged in 1989. Combination therapy can eliminate the virus in about half of all patients. Some combination treatments can do even better. One 2007 study of nearly 1,000 hepatitis C patients showed a cure rate of 99 percent after treatment with peginterferon and ribavirin -- with a number of patients remaining disease-free for as long as seven years. The prognosis for people infected with HCV is brighter than ever. And it's likely to get even brighter as doctors learn more effective combinations of existing drugs and as new drugs are developed.
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