Liver disease is the cause of a
considerable burden of illness across the European Union (EU), investigators
report in The Journal of Hepatology.
The authors calculate that 170,000 deaths each year are attributable to liver
cirrhosis, with 47,000 of these caused by liver cancer. The main causes of
liver disease were excess alcohol consumption, viral infections and obesity,
all of which are “amenable to prevention and treatment”.
The international team of investigators set
out to establish a clear understanding of the prevalence and incidence of liver
disease and its causes across the EU. They identified 260 separate studies
focusing on liver disease in EU countries. All were published in the past five
years.
Data gathered by the World Health Organization (WHO) showed that 2% of all
mortality in the EU each year, some 170,000 deaths, was due to liver cirrhosis.
The regions with the greatest cirrhosis-related mortality were south-eastern
and north-eastern Europe. However, the authors noted that there has been a
significant increase in recorded mortality attributable to cirrhosis in the UK
and Ireland over the past ten years.
Liver cancer, principally hepatocellular
carcinoma, caused 47,000 deaths annually. In 2008, incidence of liver cancer
among men and women was 11 and 4 per 100,000 persons respectively. Incidence of
death due to liver cancer was lowest in the Netherlands and highest in Italy.
Excess alcohol consumption was identified
as the main cause of liver-related death. Indeed, the authors note “Europe is
the heaviest drinking region in the world in terms of alcohol consumption”. In
France, 69% of cases of liver cancer were attributed to heavy drinking. The
incidence of alcohol-related liver mortality varied considerably, from a low of
3 per 100,000 persons in Latvia to 47 per 100,000 in Hungary.
However, health promotion initiatives in
Norway and Sweden show that the burden of alcohol-related liver death can be
reduced. Nevertheless, the investigators write “the burden of liver disease
attributable to the harmful use of alcohol is significant compared to other
aetiologies. Moreover, the burden of general health, social and economic
related issues related to alcohol consumption is substantial.”
Viral infections were also identified as a
major cause of liver disease.
Incidence of hepatitis A virus ranged from
0.55 to 1.5 per 100,000 persons. However, epidemics of hepatitis A were
responsible for transient 10-fold increases in incidence in some countries,
including the Czech Republic and Latvia in 2008. Mini-epidemics of hepatitis A
were also observed in some specific populations, and in 2002-03, an outbreak of
the infection in Finland which was initially localised to people injecting drugs,
spread to the general population.
In most cases, illness caused by hepatitis
A is mild and transient. More serious is hepatitis B virus (HBV) infection.
Annual incidence of HBV across the EU
ranged from 0.2 cases per 100,000 in Iceland to 11.2 cases per 100,000 in
France. The mortality rate due to HBV was 2.5 per 100,000 in France, with a
similar incidence observed in Spain.
But there was also some good news. Vaccine
campaigns and other health promotion initiatives meant that the rate of new HBV
infections was falling in most countries. Despite this, the authors expressed
concern that many HBV infections are undiagnosed.
Annual incidence of hepatitis C virus (HCV)
in the EU was estimated to be 6.19 infections per 100,000 persons, with
prevalence of the infection varying from 0.13% to 3.25%. Injecting drug users
were shown to have the highest burden of disease, with prevalence reaching 60%
in France. In Italy, 82% of injecting drug users seeking treatment were found
to have HCV.
Between 10 and 20% of people with
chronic HCV infection develop liver cirrhosis and 7% progress to liver cancer.
The investigators note that “patients diagnosed with hepatitis C show increased
morbidity, higher hospital admission rates and mortality rates three times
higher than that of the population.” The treatment costs of HCV are also
highlighted by the authors, who believe “patients now chronically infected with
HCV will represent a heavy disease burden in the coming years”.
Hepatitis Delta virus (HDV) can only infect
patients who also have HBV. It is associated with a more
aggressive disease course and poorer outcomes. The highest prevalence is seen
in Africa, Brazil, eastern and Mediterranean Europe, the Middle East and parts
of Asia. Prevalence of HDV co-infection among HBV-infected patients in the EU
varied between about 4% and 7%, but much higher rates were seen in individuals
who were migrants from regions where the infection is endemic.
The growing European obesity problem was
also shown to be contributing to the burden of liver disease in the EU.
Approximately 50% of adults in the EU are overweight or obese, a risk factor
for the development of non-alcoholic fatty liver disease (NAFLD). A Romanian
study found that a fifth of adults had NAFLD, and prevalence among patients
with type-2 diabetes has been recorded as high as 70%. Several studies in different
EU settings showed that NAFLD was associated with a significant increase in
mortality risk.
“The data reviewed in this study clearly
demonstrate the significant burden of liver disease in Europe,” conclude the
authors. “Liver disease associated mortality in this region is at least
comparable with other diseases that are considered to be of major public health
concern.” They hope their findings will “be the impetus for the design and
implementation of strategies that will ameliorate this problem and ultimately
save lives”.