A new US study provides more evidence of
the disproportionate impact of viral hepatitis infections on the 'baby boom'
generation. Writing in the online edition of Clinical Infectious Diseases, investigators from the newly
established Chronic Hepatitis Cohort Study (CHeCS) reported that 75% of
hepatitis C infections were among patients born between 1945 and 1964, with
half of all hepatitis B infections located in the same age group.
Both infections had a significant health
impact, with high rates of hospitalisation and death.
“The mortality rates and relative youth of
CHeCS patients who were dying was…notable,” comment the authors.
An estimated 3.2 million individuals in the
US have chronic hepatitis C infection and another 1 million have chronic
hepatitis B infection.
Neither infection has been recognised as a
serious threat to public health until recently. As a result, surveillance, prevention and
treatment programmes have been inadequate and poorly resourced.
Doctors wished to “assess the larger
implications and impact of chronic hepatitis B and C on the US population”.
They therefore established the CHeHS cohort.
The cohort involves approximately 11,000
patients who received care for either hepatitis B or C between 206 and 2008 in
the cities of Detroit (Michigan), Danville (Pennsylvania), Portland (Oregon) and
Honolulu (Hawaii). It is “dynamic”, meaning that new patients will be added to
the cohort as they enter care.
The present study reported on the baseline
demographics, liver biopsy status, hospitalisation and mortality rates with
follow-up to the end of 2010.
To be eligible for inclusion in the cohort,
participants had to be aged over 18 and have confirmed chronic hepatitis B or chronic
hepatitis C infection.
The hepatitis B-infected cohort comprised
2202 people. They had been receiving care for a median of 5.3 years and contributed
a total of 14,034 person-years of follow-up.
Approximately half were born between 1945
and 1964, with an additional 23% born between 1965 and 1974.
Most (57%) were men, 58% were Asian or
Pacific Islander and13% were black. Over three-quarters (76%) had private health
Just over a fifth (22%) had undergone liver
biopsy. On average, 9% of the cohort were hospitalised each year. A total of
706 participants (47%) had an undetectable viral load, and 58% of these individuals
had received antiviral treatment.
By the end of 2010, 9% of participants had
died. Approximately half these deaths (57%) occurred in people aged between
44 and 63 years.
The hepatitis C-infected cohort comprised
8810 participants. They had been receiving care for a median of 5.3 years.
Three-quarters of participants belong to the 'baby boom' generation and were born between 1945 and 1964. Most (60%) were
men, 70% were white and 23% were black. Just under two-thirds (62%) of participants
had private health insurance.
Viral load results were available for 63%
of patients, and the most recent values were undetectable for a fifth of these
individuals. The majority of those (80%) with an undetectable viral load had
received antiviral treatment. Overall, 38% of patients had received hepatitis C
Between 2001 and 2010, 38% of hepatitis
C-infected patients had a liver biopsy and 28% were tested for HIV. There was a
3% prevalence of HIV co-infection.
Approximately 13% of participants were
hospitalised each year. Fourteen per cent of participants had died by the end of
2010, a mortality rate of 33 per 1000 person-years. There was an especially
high mortality rate among those born during the 'baby boom' years, a quarter of
“Data from CHeCS are already yielding
unique and useful information that may be used for public health action and
policy development,” comment the investigators. “Our results strongly support
the new policy of ‘birth cohort’ testing of those born in 1945 through 1964.
This approach is likely to be more effective than the previous risk-based
testing strategy in identifying persons infected with HCV in the distant past.”
They expect the cohort will “yield much
data-driven information about the impact of therapies, comorbidities, and
conditions on the general population with HBV and HCV in the future”.