“Persistent HBV [hepatitis B virus]
infection has changed its face in the UK,” research published in the online
edition of Clinical Infectious Diseases
shows. The study found considerable diversity in viral genotype and patient
ethnicity, and that only one in three patients were taking therapy. There was
extensive use of non-recommended treatment and approximately a third of treated
patients had drug-resistant virus. Few people had been tested for
co-infections such as HIV. The investigators believe their findings have
important implications for those planning hepatitis B services and show the
“globilisation” of the epidemic.
Persistent hepatitis B virus infection is
associated with progressive liver disease and a high risk of hepatocellular
carcinoma.
There are ten known hepatitis B genotypes,
each of which has a specific geographical distribution. It is possible that
migration has altered the ethnic populations affected by hepatitis B in the UK
and the genetic diversity of the virus.
Investigators therefore obtained
information on a snapshot sample of people attending specialist hepatology
clinics in the UK. Demographic, clinical and laboratory data were collected.
A total of 698 people who received
care for chronic hepatitis B infection between 2007 and 2009 were recruited.
“This national cross-sectional study of
persistent HBV infection represents a snapshot of current disease burden of
patients attending…liver clinics in the UK,” write the authors. “We believe
that the patients in this study are likely representative of the clinic
population from which they are drawn and that the study provides
characterisation of both patients and viruses.”
Most of the patients were men (61%), who
were significantly older than female patients (mean age 45 vs 38 years, p <
0.001). Participants originated from 61 different countries and all the major
ethnicities were represented, the largest being East and South East Asian
(37%), White (25%), South Asian (20%) and Black African (15%).
Overall, 80% of patients were born outside
the UK.
Consumption of alcohol is known to
accelerate liver damage in the context of hepatitis B infection, and a third of
patients were recorded as regularly drinking alcohol.
Just over a fifth of patients were HBeAg
seropositive.
Differences were apparent in the treatment
and care of men and women. Men were significantly more likely than women to
have undergone a liver biopsy (53 vs 23%, p < 0.0001) and to be taking
antiviral treatment (45 vs 17%, p 0.0001). A fifth of patients who had
undergone a liver biopsy were found to have cirrhosis. Rates of cirrhosis were
significantly higher in men than women (24 vs 8%, p = 0.006). There were ten
cases of hepatocellular carcinoma, nine of which were in men.
A total of eight hepatitis B genotypes were
identified. Genotype D was the most common, representing 31% of all infections.
Genotypes A, B and C were each found in approximately a fifth of patients.
There was a strong association between
genotype and e antigen status. Patients with genotype A and C viruses were
significantly more likely to be e antigen positive (30 and 41% respectively; p
= 0.001).
Only a third of patients were taking
hepatitis B therapy, with just 18% taking recommended first-line treatment. Approximately
a third (31%) of those on treatment were taking lamivudine monotherapy. The
investigators found this “disconcerting”, noting that this treatment strategy
is not recommended and “associated with rapid development of resistance, severe
hepatic flares and decompensation as well as limiting future treatment
options.”
Drug-resistant hepatitis B was detected in
27% of patients who had undergone treatment.
Some 16% of patients not currently on
therapy had hepatitis B DNA above 2000 iu/ml and ALT levels above the upper
limit of normal, “indicating a need for treatment.”
Guidelines recommend that hepatitis
B-infected patients should be tested for other viral co-infections. However,
only 31% of patients had documented HIV test results. Nine patients were known
to be co-infected with HIV. Approximately half the patients had been screened
for hepatitis C, and seven patients had antibodies for this infection. Only a
third of patients had been tested for hepatitis delta, which “is associated
with a more rapidly progressive clinical course” of hepatitis B infection.
“Those planning, commissioning and managing
hepatology services must now take host virus diversity into account,” conclude
the authors. “Optimal management requires awareness of the variable patterns of
chronic HBV in countries of origin.”