Viral hepatitis is now the seventh most important cause of death worldwide

Michael Carter
Published:
13 July 2016

Viral hepatitis is a leading cause of death and disability worldwide, data from the Global Burden of Disease Study published in The Lancet shows. Between 1990 and 2013, the number of deaths attributable to viral hepatitis increased by almost two-thirds. Hepatitis B virus (HBV) and hepatitis C virus (HCV) accounted for 96% of viral hepatitis-related mortality in 2013.

“To our knowledge, this study is the first to formally estimate the burden of viral hepatitis using systematic data gathering and robust statistical methods,” comment the investigators. “Our results show that viral hepatitis is one of the leading causes of death and disability worldwide, and causes at least as many deaths annually as tuberculosis, AIDS, or malaria.”

Authors of an editorial state that the data presented in the study “are key” to advocating for a global strategy to tackle viral hepatitis. They also call for improved national estimates so the success of such a strategy can be monitored.

There have recently been significant advances in the prevention and treatment of viral hepatitis. There are now highly effective vaccines against hepatitis A virus (HAV) and HBV. Therapies for HBV and HCV have also been developed. These developments have overcome some of the barriers for the control and treatment of viral hepatitis and are likely to be key to new health strategies. Reliable data are needed to guide the development of such strategies.

An international team of investigators therefore examined data collected from the Global Burden of Disease Study between 1990 and 2013 to estimate changes in illness and death due to acute viral hepatitis and also the burden of morbidity attributable to chronic infection with HBV and HCV. They adjusted their findings by age and sex and broke down the data according to world region.

Between 1990 and 2013, deaths due to viral hepatitis increased from 890,000 to 1.45 million, a 63% increase. The number of life-years lost due to viral hepatitis C mortality increased by 34% and there were similar increases in the number of viral hepatitis-related disability life-years and life-years lived with disability because of hepatitis.

However, after taking into account demographic changes – increasing population size and ageing population – the number of life-years lost due to viral hepatitis declined by 20% between 1990 and 2013 and there was a 13% fall over the study period in life-years with disability.

“Increases in absolute mortality and disability seem to be driven primarily by demographic change – most notably population growth,” write the researchers.

Viral hepatitis (acute and chronic) was the tenth most important cause of death globally in 1990 but the seventh most important in 2013. Over the same period, other communicable diseases, including malaria and tuberculosis, declined in importance.

When combined, HBV and HCV accounted for 96% of viral hepatitis-related mortality and 91% of viral hepatitis-related disability life-years in 2013. This was little changed compared to 1990.

In 2013, HBV and HCV accounted for almost equal proportions of viral hepatitis-related deaths (47% vs. 48%). Most of the mortality attributable to liver cancer and cirrhosis had HBV and HCV as the underlying cause.

There were regional differences in mortality patterns. Most of the mortality due to acute HAV and hepatitis E virus was located in sub-Saharan Africa and Asia.

In 2013, the number of deaths in low- and middle-income countries was lower in poorer countries (610,000) compared to richer countries (840,000). However, age-standardised mortality and disability life-year rates were higher in poorer compared to richer settings. Rates of illness and death attributable to viral hepatitis remained stable in richer countries but increased in poorer ones.

“The small proportion of global health funding targeted at viral hepatitis is disproportionate to its importance as a major cause of death and disability,” conclude the investigators. “Our results suggest that an evolution in funding structures is required to accommodate the burden of viral hepatitis and allow effective responses in low-income and lower-middle-income countries.”

In their editorial, investigators from the World Health Organization state that the study “provides convincing evidence that viral hepatitis is a major contributor to the global disease burden and shows that this disease requires a stronger national and international response.”

They suggest such responses need to consist of the following:

  • Interventions to prevent new infections: vaccinations, safe health care, harm reduction.
  • Scaling up of testing and treatment.
  • Additional allocation of money from health budgets to hepatitis programmes in richer countries.
  • Increased international assistance for poorer settings.

Reference

Stanaway JD et al. The global burden of viral hepatitis from 1990 to 2013: findings from the Global Burden of Disease Study 2013. The Lancet, http://dx.doi.org/10.1016/s0140-6736(16)30579-7.

Wiktor SZ et al. The global burden of viral hepatitis: better estimates to guide hepatitis elimination efforts. The Lancet, http://dx.doi.org/10.1016/s0140-6736(16)31018-2.