| |
Hepatitis A Virus Testing and Vaccination Rates are Low in HCV+ Patients
|
| |
| |
"Susceptibility to hepatitis A in patients with chronic liver disease due to hepatitis C virus infection: Missed opportunities for vaccination"
Hepatology
Sept 2005
Michael Shim, Inessa Khaykis, James Park, Edmund J. Bini *
Department of Medicine and Division of Gastroenterology, VA New York Harbor Healthcare System and NYU School of Medicine, New York, NY
".....Although the overall case-fatality rate of acute HAV (hepatitis A virus) among persons of all ages is only 0.01% to 0.3%, it is higher (1.8%) among adults 50 years of age and older. More importantly, acute HAV superinfection causes severe liver disease, acute liver failure, and even higher mortality rates in patients with underlying chronic liver disease (such as HCV or HBV). In a prospective cohort study of adults with chronic hepatitis C virus (HCV) infection, Vento et al. reported that 41.2% of patients with acute HAV superinfection developed acute liver failure, and 35.3% died. Numerous other studies have also identified chronic liver disease as a risk factor for fulminant hepatitis and death from acute HAV infection....
.....In a large retrospective cohort study, we showed that a substantial proportion of patients with chronic HCV infection did not have HAV antibody testing performed, and most of the susceptible patients were never vaccinated against HAV. The low rates of HAV testing and vaccination are striking given the presence of recommendations to vaccinate these individuals against HAV since 1996, the long duration of follow-up, and the high number of visits with their primary care provider. These findings have substantial public health implications and represent missed opportunities for prevention....
..... The reasons for these low rates of HAV testing are likely multifactorial, including patient barriers, provider barriers, and other system-based factors. Patient-related barriers potentially include refusal and poor compliance, whereas provider-related barriers may include lack of knowledge regarding HAV antibody testing, lack of time or resources, or other unidentified reasons....
.... Another important finding in our study was that only half of the patients who were vaccinated received the full vaccination course....
....in addition to demonstrating that HAV testing and vaccination rates were low in patients with chronic HCV infection, we determined that the incidence rate of acute HAV infection in our subjects was 1.82 per 1,000 person-years. More importantly, 1 of the 3 patients who developed acute HAV infection died of acute liver failure, and this case-fatality rate was similar to what has been reported by other investigators...
..... Public health efforts aimed at raising awareness about HAV vaccination in patients with chronic liver disease should be strongly encouraged. In addition, further studies to evaluate patient and provider barriers to HAV vaccination are needed to prevent future missed opportunities for vaccination....."
Abstract
Hepatitis A virus (HAV) superinfection is associated with a high risk of liver failure and death in patients with underlying chronic liver disease. Although HAV vaccination is recommended for all patients with chronic hepatitis C virus (HCV) infection, little is known about adherence to these recommendations in clinical practice.
The aims of this study were to determine the frequency of HAV testing and vaccination among patients with chronic HCV infection. We conducted a retrospective cohort study of 1,193 patients diagnosed with chronic HCV infection over a 1-year period. During 1,646 person-years of follow-up, patients were seen by their primary care provider a median of 10.0 times (interquartile range, 4.0-20.0).
HAV antibody testing was performed in 640 subjects (53.6%), and 317 (49.5%) of those tested were susceptible (HAV antibody negative).
Only 94 of the 1,193 patients (7.9%) received the HAV vaccine, including 26.8% of the 317 susceptible patients, 0.9% of the 323 patients who were already immune to HAV, and 1.1% of the 553 subjects who were never tested.
Among the 94 vaccinated patients, 45 received only one dose of the vaccine. Three of the unvaccinated patients developed acute HAV infection during follow-up, and 1 of them died of acute liver failure.
In conclusion, despite published recommendations to vaccinate against HAV in patients with chronic HCV infection, we found that HAV testing and vaccination rates were low in clinical practice. Public health programs to increase awareness about HAV vaccination in patients with chronic liver disease are needed.
BACKGROUND
The hepatitis A virus (HAV) is an important cause of acute hepatitis worldwide, and this virus has been responsible for numerous disease outbreaks from close personal or sexual contact,[1-3] contaminated food or water,[1][4-7] injection drug use,[8][9] and other modes of transmission.[8][10] Despite the availability of the HAV vaccine since 1995, HAV infection continues to be one of the most common vaccine-preventable illnesses in the United States.[11] After adjusting for asymptomatic illness and disease underreporting, the Centers for Disease Control and Prevention estimated that 180,000 cases of HAV infection occurred in the United States in 1997.[11] In addition, the economic burden of acute HAV infection in the United States has been estimated at more than $300 million annually.[12]
Although the overall case-fatality rate of acute HAV among persons of all ages is only 0.01% to 0.3%,[11][13][14] it is higher (1.8%) among adults 50 years of age and older.[11] More importantly, acute HAV superinfection causes severe liver disease, acute liver failure, and even higher mortality rates in patients with underlying chronic liver disease. In a prospective cohort study of adults with chronic hepatitis C virus (HCV) infection, Vento et al.[15] reported that 41.2% of patients with acute HAV superinfection developed acute liver failure, and 35.3% died. Numerous other studies have also identified chronic liver disease as a risk factor for fulminant hepatitis and death from acute HAV infection.[4][16-22]
Based on the potential risk for fulminant hepatic failure and death from acute HAV superinfection, the 1996 Advisory Committee on Immunization Practices recommended HAV vaccination for all patients with chronic liver disease, including those with chronic HCV infection.[23] These recommendations have also been endorsed by the World Health Organization,[24] the National Institutes of Health,[25] the United States Veterans Health Administration,[26] the American Association for the Study of Liver Diseases,[27] the American Liver Foundation,[28] the American College of Gastroenterology,[29] and others.[30-33] However, little is known about adherence to these recommendations in clinical practice. The aims of the current study were to determine the frequency of HAV antibody testing in patients with chronic HCV infection, to evaluate the proportion of those tested who were susceptible to HAV, and to investigate whether susceptible patients were vaccinated against HAV infection according to published guidelines.
Study Population.
We identified all patients who had HCV antibody testing performed over a 1-year period from January through December 2000 at the Veterans Affairs (VA) New York Harbor Healthcare System in New York. The VA New York Harbor Healthcare System consists of 2 main VA medical centers located in New York, NY and Brooklyn, NY. Patients were identified using our computerized patient record system and were included in this study if they were newly diagnosed as being HCV antibody and HCV RNA positive. Patients were excluded from this study if they had undetectable HCV RNA by polymerase chain reaction testing, if HCV RNA testing was not performed, or if they were co-infected with HIV. The study protocol was reviewed and approved by the Institutional Review Board at our medical center.
Study Design.
Demographic and clinical information were collected by reviewing the electronic medical record of all HCV-positive patients. Data collected on each patient included age, sex, race/ethnicity, current or prior injection drug use, current use of alcohol (>3 drinks per day), active psychiatric disease, whether they were homeless, whether they had sex with a same-sex partner, history of sexually transmitted diseases, and the presence of cirrhosis. Patients were considered to have active psychiatric disease if so diagnosed by a psychiatrist and if they were receiving treatment for the condition. The diagnosis of cirrhosis was made by liver biopsy or by compatible findings on physical examination or abdominal imaging. Although our computerized record system and pharmacy database are very comprehensive, certain data (such as history of sexually transmitted diseases) were not as well documented. However, the other demographic and clinical data were complete for all patients.
Follow-up data were collected through June 30, 2002 by reviewing the electronic medical record for each patient to determine the number of HCV-infected patients who had HAV antibody testing performed and the number who actually received HAV vaccination. To ensure that all patients who received the HAV vaccine were identified, we also reviewed our computerized pharmacy database. The duration of follow-up was calculated from the time of diagnosis of HCV infection until the date that the patient was last seen in the hospital or outpatient clinic.
Study Outcomes.
The primary outcome measure of this study was the proportion of patients with chronic HCV infection who were vaccinated against HAV. Patients were considered vaccinated if they had received at least 1 dose of any of the commercially available HAV vaccines.
The secondary outcome measures included the number of doses of HAV vaccine received, whether HAV antibody testing was performed, the proportion of patients who were susceptible to HAV among those who were tested, factors associated with HAV antibody testing and HAV vaccination, and the incidence of acute HAV infection during follow-up. Susceptibility was defined as a negative total HAV antibody.
|
|
| |
| |
|
|
|
