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”.
Blachier M et al. The burden of liver disease in Europe: a review of the available epidemiological data. Journal of Hepatology 58: 593-608, 2013.