Any level of hepatitis B virus (HBV) viremia was associated with increased hepatocellular carcinoma (HCC) risk in adults with HIV/HBV coinfection, according to new research presented at the Conference on Retroviruses and Opportunistic Infections (Abstract 136).
sarathsasidharan/Thinkstock
“Chronic HBV coinfection is common among people with HIV, but the determinants of HBV-associated HCC are not well characterized,” said presenter H. Nina Kim MD, MSc, of the University of Washington, Seattle. “We sought to identify factors that contribute to HCC development in persons with HIV/HBV coinfection to guide early detection and prevention measures.”
The researchers conducted a longitudinal cohort study within the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD), a collaboration of single-site and multisite cohorts throughout the United States and Canada; 22 cohorts from NA-ACCORD were included in the analysis.
Potential HIV and HBV risk factors were examined, including viremia and CD4 percentage, as well as HBV DNA levels. Traditional risk factors for liver disease progression, including age, sex, and heavy alcohol use, were also assessed.
Eligible patients were 18 years of age or older who were followed for at least 6 months, had evidence of chronic HBV, and had HIV RNA or CD4+ cell measurement during this period. Persons with prevalent HCC at baseline were excluded.
The primary outcome was first occurrence of HCC, which was adjudicated by medical chart review and/or cancer registry. Multivariable Cox regression was used to determine adjusted hazard ratios of risk factors.
Results
Among 9,383 HIV/HBV-coinfected individuals identified, 8,354 (89%) were included in the analysis. The median age of participants was 43 years and 93.1% were male. Heavy alcohol use (35.3%) and chronic hepatitis C virus (HCV) coinfection (21.6%) were common among participants.
Among 8,354 eligible participants, 115 developed HCC over a median 6.9 years of follow-up (incidence rate, 1.8 events per 1,000 person-years; 95% confidence interval [CI], 1.5-2.1).
Independent risk factors for HCC were chronic HCV coinfection (adjusted hazard ratio [aHR], 1.60 [95% confidence interval, 1.07-2.39]), age 40 years and older (aHR, 2.14 [1.36-3.37]), and heavy alcohol use (aHR, 1.51 [1.03-2.21]); however, time-updated CD4+ percentage less than 14% (aHR, 1.03 [0.56-1.90]) and time-updated HIV RNA level over 500 copies/mL (aHR, 0.88 [0.55-1.41]) were not associated with HCC risk.
In a second model, among 3,054 patients who had HBV DNA measured, the risk of HCC was higher with HBV DNA levels greater than 200 IU/mL (aHR, 2.70 [1.23-5.93]), and the risk was particularly elevated at levels greater than 200,000 IU/mL (aHR, 4.34 [1.72-10.94]).
The researchers also found that the risk of HCC was significantly lower in patients with HBV DNA suppression less than 200 IU/mL receiving HBV-active ART for 1 year or more (aHR, 0.42 [0.24-0.73]). In addition, a dose-response relationship was observed between the duration of suppression and this protective effect.
Dr. Nina Kim acknowledged that a key limitation of the study was inconsistent monitoring of HBV DNA level while patients were on treatment. Furthermore, given the demographics of the cohort, these results may not be generalizable outside of North America.
“Our study was the first to show that any level of HBV viremia using 200 as a threshold of detection was associated with HCC risk in a large regionally diverse cohort of adults outside of Asia,” Dr. Kim said. “To gain maximal protective benefit from antiviral therapy for HCC prevention, sustained and ideally uninterrupted suppression of HBV may be necessary over years.”
“HIV/HBV coinfected patients can take much longer than a year to achieve less than 200 copies on HBV DNA due to their baseline levels, but we still don’t know if HBV therapy intensification could hasten this process,” said moderator Robert T. Schooley, MD, of the University of California, San Diego.
Dr. Kim disclosed no conflicts of interest. The study was supported by multiple sources, including the National Institutes of Health, the Centers for Disease Control and Prevention, and the National Cancer Institute.