DDW: Study Backs HCV Screens for All Boomers
CHICAGO -- Screening all baby boomers for hepatitis C virus (HCV) infection
could save tens of thousands of lives at a very acceptable cost, a
researcher said here.
If everyone born from 1946 to 1964 were screened for the virus, about 48,000
fewer HCV-related deaths could be expected in this population, given current
patterns of treatment among individuals diagnosed with HCV infection, said
Lisa McGarry, MPH, of the research firm Innovus in Medford, Mass.
Another 11,000 lives could be saved by expanding the screening population to
include those born from 1965 to 1970, McGarry told attendees here at
Digestive Disease Week.
Current screening guidelines call for testing only in patients with certain
risk factors, such as injection drug use and sex with other infected
individuals.
McGarry said that many baby boomers are believed to have been infected with
HCV before testing was introduced and don't know it or don't consider
themselves at risk. Estimates are that some three-quarters of people with
HCV are unaware of it.
These individuals are at high risk to develop liver disease, which may be
less responsive to treatment when it has become symptomatic. The result for
such people is transplantation and/or death in many cases, she pointed out.
Since the current risk-based screening is unlikely to reach many of these
cases, an obvious alternative is simply to screen everyone in the boomer
generation, McGarry said.
The study she reported here was a computer simulation, comparing projections
of HCV diagnoses and outcomes that would be expected in individuals in the
1946-1964 birth cohort with the current risk-based screening strategy versus
a universal age-based approach.
For the base case, the simulation used estimates of screening rates and
yields from the literature. About 8 million people are screened each year.
Out of the general population, this screening identifies 0.72% of females
and 0.62% of males as noninfected and 2.85% of females and 2.82% of males as
infected.
The age-based strategy was assumed in the model to reach all of the 80
million people in the 1946-1964 birth cohort during the first five years of
implementation.
For both simulations, literature-based estimates of likelihood of achieving
sustained virologic responses with current therapies, and rates of
progression to the different stages of fibrosis, transplantation, and death
stratified by age at infection and sex were included in calculating annual
risks.
Over the expected lifetime of Baby Boomers, McGarry reported that the
universal screening strategy would result in the following reductions in
adverse outcomes, relative to risk-based screening:
Compensated cirrhosis cases: -112,881
Decompensated cirrhosis cases: -52,787
Hepatocellular carcinoma cases: -28,634
Liver transplants: -5,914
Deaths from HCV-related causes: -47,953
After seeing these numbers, McGarry and colleagues then examined whether
adding another six years to the cohort would make a significant difference.
With screening extended to individuals born from 1965 to 1970 -- increasing
the total screening population to 102 million -- the adverse outcomes were
reduced by another 20%, she reported, including an additional 11,000 deaths
prevented.
She said the additional screening would be more expensive overall than the
current strategy. The additional screening and treatment costs would
significantly exceed the savings associated with fewer cases of advanced
disease and transplantation.
But her group estimated these extra costs at about $25,000 per
quality-adjusted life-year saved, which she said is well within the
boundaries normally considered acceptable for disease screening -- in the
same range as mammography for breast cancer and screening for prostate
cancer.
McGarry listed several limitations of the analysis, including the likely
inability to screen 100% of such a large population in actual practice.
"That's why it's a model," she quipped during a press briefing on the study.
She also noted that the model did not take account of newer treatment for
HCV, such as protease inhibitors, that are expected to become available in a
matter of weeks. The model also relied on assumptions and data from a wide
variety of sources.
The model results were especially sensitive to rates of treatment and
response rates, she said.
Adrian Di Bisceglie, MD, of St. Louis University, who moderated the press
briefing, said the Department of Health and Human Services is scheduled to
release a new action plan on hepatitis virus screening that may recommend
changing the scope of HCV screening.
"I think they'll be looking at strategies like this," he said.
The study was funded by Vertex Pharmaceuticals.
McGarry said she had no relevant financial interests. Other study authors
reported relationships with Bristol-Myers Squibb, Genentech, Schering,
Tibotec, Vertex, Salix, and Biolex.
Di Bisceglie reported relationships with Abbott, Anadys, Bristol-Myers
Squibb, Gilead Sciences, GlobeImmune, Novartis, Pharmasset, Projects In
Knowledge, Roche, Schering- Plough, and Vertex.
Primary source: Digestive Disease Week
Source reference:
McGarry L, et al "The impact of birth-cohort screening for hepatitis c virus
(HCV) compared with current risk-based screening on lifetime incidence of
and mortality from advanced liver disease (Advld) in the United States" DDW
2011; Abstract 477.