Miriam E. Tucker
November 08, 2013
WASHINGTON, DC — Screening baby boomers in the care of the US Department of Veterans Affairs (VA) for hepatitis C virus, as well as those seen in emergency departments, yields particularly high infection rates, 2 new studies have found.
The prevalence of confirmed hepatitis C infection in these settings — 9.9% in the VA and 8.7% in the emergency department — is about triple the overall 3.3% prevalence seen in those born from 1945 to 1965 — the so-called baby boomer cohort.
Results from the 2 studies were presented here at The Liver Meeting 2013.
Our assumption was that we would pick up 3% of patients with hepatitis C. These 2 presentations indicate that in VA and emergency department settings, our assumptions need to be adjusted, said session comoderator Donald Jensen, MD, director of the Center for Liver Diseases at the University of Chicago Medical Center.
"In these enriched populations, we're going to pick up many, many more patients. We have to be able to identify these individuals and link them to care," he told Medscape Medical News.
Many Vets Remain Undiagnosed
The VA data were presented by Lisa Backus, MD, from the VA Office of Public Health/Population Health and the Veterans Health Administration in Palo Alto, California.
Her team identified 5,500,392 veterans in the VA Corporate Data Warehouse who had at least 1 outpatient visit in 2012.
Most of the patients were male (93%), 65% were white, 15% were black, and 6% were Hispanic. Nearly half (46.2%) were born from 1945 to 1965, 37.4% were born before 1945, and 16.4% were born after 1965.
At some point from 1999 to 2012, 54.7% had undergone antibody testing for hepatitis C.
Veterans in the baby boomer cohort were more likely to have undergone screening than those in the younger and older cohorts (64.2% vs 58.0% vs 41.5%).
Nevertheless, 35.8% of the baby boomer cohort had not undergone hepatitis C screening, Dr. Backus reported.
Of the 215,354 veterans who tested positive for hepatitis C antibodies, 95.1% had confirmatory testing with viral load or genotype tests.
Rates of confirmatory testing were highest in the baby boomer cohort, but were still high in the younger and older cohorts (95.8% vs 94.1% vs 88.6%).
"The high rate of confirmatory testing increases confidence in the observed infection prevalence," she noted.
The prevalence of hepatitis C infection was considerably higher in the veteran population than in the general population in the United States (6.1% vs 1.2%). It was also higher in the veteran baby boomer cohort than in the baby boomer population in the United States (9.9% vs 2.5%).
The prevalence of hepatitis C infection was much higher in veterans first screened in 1999 than in those first screened in 2012 (33.2% vs 5.7%).
The researchers extrapolated the most recent hepatitis C infection prevalence to the 905,571 veterans in the baby boomer cohort who had not been screened, and estimated that screening would identify 51,000 veterans, Dr. Backus explained.
After the presentation, an audience member asked if there might have been selection bias because those screened before the 2012 recommendation from the CDC that all baby boomers be screened would have been more likely to have had symptoms.
Dr. Backus noted that this would be less likely in the VA population because many VA centers began screening their populations in 2005, after a study suggested that Vietnam-era military service was a risk factor (Hepatology. 2005;41:88-96).
"In a way, we were already doing some birth-cohort screening, functionally based on year of service," she noted.
Six-week data from an emergency department hepatitis C screening program were presented by James Galbraith, MD, associate professor of emergency medicine at the University of Alabama at Birmingham.
Emergency Department a Screening Venue
Previous studies have suggested that nonwhites, Medicaid recipients, and the uninsured are all disproportionately affected by hepatitis C, and that those who lack insurance coverage and a usual source of medical care are less likely to know their hepatitis C status. "This suggests that screening efforts that work through the healthcare system might not be successful in reaching individuals infected with hepatitis C," Dr. Galbraith said.
These facts led the emergency department at his institution to initiate a routine opt-out hepatitis C baby boomer screening program, similar to the all-ages screening program that had been established for HIV at the institution.
During the study period — from September 3 to October 17 — 2363 unique visits to the emergency department were made by baby boomers. Nurses administered questionnaires to 1721 of these patients that asked whether they had ever been tested for hepatitis C, and if they had, if they knew their status.
Overall, 1287 patients (74.8%) were unaware of their status, and 984 underwent testing for hepatitis C antibodies. Of those, 118 patients (12.0%) had antibodies for hepatitis C — 71 had positive confirmatory viral RNA results, 27 had negative viral results, and 20 have not yet had the confirmatory test.
Males were more likely than females to have positive antibody screening tests (16.5% vs 7.7%; P < .001) and positive confirmatory RNA results (80.0% vs 57.6%), but there were no differences by race.
Table. Insurance Status of Patients With Positive Results*
|Public or Medicaid||17.2|
*P < .001 for all.
There were no significant differences in confirmed hepatitis C viremia when comparing insurance type or race, Dr. Galbraith noted.
On the basis of the 6-week data, 1-year projection suggests that 7872 emergency department patients would be screened, and 864 would be antibody-positive, Dr. Galbraith reported.
Dr. Jensen said he wondered whether all the patients understood the questionnaire. "In my practice, I see patients who think hepatitis C is what you get after you've had hepatitis B. I don't think you can just ask people if they've had hepatitis C. A lot of people don't know what that is," he told Medscape Medical News.
Of course, finding a way to link patients tested in the emergency department with care is an issue, given that many are underinsured or uninsured and lack access to primary care services.
Dr. Galbraith said he was "very surprised" by the degree of hepatitis C reactivity, and that his emergency department has been "overwhelmed" by the volume of patients newly diagnosed with chronic hepatitis C. Before the program started, his team suspected that the prevalence would be less than half of what it was. "This degree of reactivity has had a tremendous impact on our timeliness to provide linkage to care and costs, including linkage to care and confirmatory testing," he said.
“We're now seeing a second blip in the 20s, mainly among injection drug users.”
Although his emergency department has established a process for helping newly diagnosed patients to obtain a primary care physician and a hepatitis C specialist, Dr. Galbraith explained that "the greatest barrier is not the availability of specialists, but rather the financial barriers related to a lack of health insurance or the ability for many of these individuals to pay."
There have been delays for Medicaid-dependent patients obtaining a primary care appointment and the subsequent Medicaid-required referral to the hepatitis treatment specialist. "We have overcome these barriers for many already, but there is a growing list of patients in need, and the resource requirement is large," Dr. Galbraith told Medscape Medical News.
"A nationwide focus on linkage to care for these disproportionately affected populations is needed," he added. "Mirroring successes in our emergency department linkage to care for newly diagnosed HIV-infected individuals will be a start. We are hopeful that we will provide every person identified in our screening with the opportunity to see a liver specialist."
Making matters potentially worse is the recent emergence of hepatitis C infection in young adults, Dr. Jensen told Medscape Medical News.
We're now seeing a second blip in the 20s, mainly among injection drug users," he said. "We can't do everything, so we need to focus and not spread ourselves too thin. For now, just screening the baby boomer cohort will identify 800,000 new cases."
Dr. Galbraith has disclosed no relevant financial relationships. Dr. Jensen reports financial relationships with Abbott Laboratories, Astex Pharmaceuticals, Biotica Technology, Boehringer Ingelheim, Bristol-Myers Squibb, Genentech, Gilead Science, Inhibitex, Johnson & Johnson, Merck, Pharmasset, Roche, Tibotec, and Vertex Pharmaceuticals.
The Liver Meeting 2013: American Association for the Study of Liver Diseases (AASLD). Abstracts 21 and LB-6. Presented November 3 and 4, 2013.