Only 15% of US veterans have been tested for hepatitis B virus (HBV) infection, and among those who tested positive just one-quarter received antiviral treatment and 13% were screened for liver cancer – although both measures were shown to reduce the risk of death – researchers reported on Sunday at the American Association for the Study of Liver Diseases (AASLD) Liver Meeting in Boston, United States.
Marina Serper and colleagues from the Philadelphia Veterans Affairs (VA) Medical Center and the University of Pennsylvania aimed to identify gaps in recommended hepatitis B care in the US.
An estimated 1.25 million people are infected with HBV in the US, the researchers noted as background. While the AASLD and other professional groups have established guidelines for testing, care and treatment, studies suggest these are not routinely followed.
The Veterans Health Administration is the largest provider of hepatitis care in the US, and its centralised care and data collection facilitates analysis of procedures and outcomes in the absence of a national health system. However, the veteran population does not reflect the American population as a whole.
The researchers conducted a retrospective cohort analysis using data from the Corporate Data Warehouse, a national database containing claims, clinical data, pharmacy records and death records, during the period 1999 through 2013.
Out of 16,718,682 individuals with at least two visits to VA health facilities, a total of 2,533,862 – or 15% – had a record of being tested for hepatitis B surface antigen (HBsAg). Among those who were tested, 21,828 individuals – or 0.9% – were found to be HBsAg-positive. (People who died within one week of receiving a positive HBsAg test were excluded from further analysis.)
HBsAg positivity is the usual method of determining whether someone currently has hepatitis B. People may have anti-HBV antibodies due to either vaccination or having naturally cleared a previous infection (which occurs in more than 90% of people infected as adults). Therefore, HBsAg is a better indication of who is eligible for hepatitis B care and treatment.
In the HBsAg-positive group, most were men (typical of a veteran population) and the median age was 52 years. About half were white, 41% were African-American, 5.4% were Asian and 2.4% were American Indian or Native Hawaiian. Nearly one-fifth (17%) also had hepatitis C virus and 4.7% had HIV co-infection. Nearly 40% had a record of significant alcohol use and 8.3% had diagnosed liver cirrhosis. One-third had alanine aminotransferase (ALT) levels at least twice the upper limit of normal, suggesting active liver inflammation.
A total of 6744 veterans with hepatitis B – or 31% – were referred for specialty care. Looking at laboratory testing, overall 73% had received ALT tests, 26% received HBV DNA viral load tests, 40% were tested for hepatitis B 'e' antigen (HBeAg, a marker for viral replication and a predictor of treatment response), 46% were tested for hepatitis B 'e' antibodies, 42% were tested for hepatitis A and 7.9% were tested for hepatitis D or delta (a defective virus that only occurs with HBV and can lead to more severe liver disease). Among people referred to specialty care, testing rates improved significantly, to 99%, 59%, 65%, 73%, 73% and 15%, respectively.
Regarding other types of care, only 1.8% of all HBsAg-positive people and 3.0% of those in specialty care received recommended hepatitis A vaccinations (after excluding about 5400 people who were already immune due to vaccination or prior naturally cleared infection).
One-quarter received antiviral treatment for hepatitis B, rising to 38% among those with elevated ALT. For people in specialty care, treatment rates were 44% and 49%, respectively.
Screening for hepatocellular carcinoma (HCC, a type of primary liver cancer) is recommended for people with active hepatitis B, especially those with cirrhosis. Yet only 13% of HBsAg-positive patients overall, and 18% of those in specialty care, received HCC screening. These figures excluded nearly 8700 people under the age of 50 – as HCC usually occurs in older people with long-term disease progression – though many experts believe younger at-risk people should be screened as well.
Turning to clinical outcomes, the overall incidence of liver cancer was 4.5 cases per 1000 person-years. The rate was 3.7 per 1000 person-years among people referred to specialty care compared with 7.1 per 1000 person-years among those not receiving such care – a significant risk reduction of about 50% (IRR 0.52%).
The overall rate of hepatic decompensation, or liver failure, was 8.4 cases per 1000 person-years. Here, the rate was higher among people in specialty care (14.3 vs 6.7 per 1000 person-years, respectively), which may indicate that people with more advanced disease were more likely to get special care. However, all-cause mortality rates for patients with and without specialty care (36.0 vs 37.7 per 1000 person-years, respectively) did not differ significantly (IRR 1.05).
A multivariate analysis of predictors of mortality found that HCC screening was associated with a 20% reduction in the risk of death during 2000-2010 and a 36% reduction during 2010-2013 (HR 0.80 and 0.64). Antiviral therapy had a smaller effect, reducing mortality risk by 4% during 2000-2010 and by 17% during 2010-2013, with only the later period being statistically significant (HR 0.96 and 0.83).
Based on these findings, the researchers concluded that there are "significant gaps in recommended HBV care in the US." They recommended that clinical decision support tools should be developed to improve guidelines adherence and clinical outcomes in people with hepatitis B.
Serper M et al. Serologic testing rates among US veterans with hepatitis B. American Association for the Study of Liver Diseases (AASLD) Liver Meeting, Boston, abstract 68, 2014.