Metabolic Syndrome Can Increase the Risk of Liver Cirrhosis in Chronic Hepatitis B by over Fourfold
Chronic hepatitis B is the commonest cause of liver cancer in Hong Kong. Liver cirrhosis greatly increases the risk of liver cancer in hepatitis B patients. Determination of the risk factors of liver cirrhosis is important to identify high risk patients who may need anti-viral treatment and intensive cancer surveillance.
In Hong Kong, approximately 10%-15% of the population has metabolic syndrome, which is defined as central obesity plus any of the following 2 features: high serum triglyceride, low serum high density lipoprotein (HDL) cholesterol, hypertension and diabetes mellitus. In 2006, the Center for Liver Health at The Chinese University of Hong Kong (CUHK) demonstrated that metabolic syndrome is associated with fatty liver disease, which may progress into liver cirrhosis. However, the relationship of metabolic syndrome and chronic hepatitis B on the risk of liver cirrhosis is still unclear.
Between 2006 and 2008, a research team led by Professor Henry Chan Lik-yuen, Chairman of the Center for Liver Health at CUHK, conducted a study receiving referrals of chronic hepatitis B patients from all primary care and hospital clinics in Hong Kong to investigate the effect of metabolic syndrome on liver cirrhosis. All patients were carefully assessed in the Prince of Wales Hospital for the presence of metabolic syndrome and liver cirrhosis by transient elastography, Fibroscan, a non-invasive method that can detect liver cirrhosis with high accuracy. Among the 1,466 patients recruited into this study, 188 (13%) patients had metabolic syndrome. The commonest components of metabolic syndrome were central obesity (41%) and high blood pressure (45%), while other components including hypertriglyceridemia (13%), low HDL cholesterol (18%) and diabetes mellitus (14%) were present in a smaller proportion of patients. 46 of 188 (24%) patients with metabolic syndrome versus 141 of 1,278 (11%) patients without metabolic syndrome had liver cirrhosis.
The results also showed that the presence of more components of metabolic syndrome in the same patient was associated with a higher risk of liver cirrhosis. A patient with 3 components of metabolic syndrome had the risk of liver cirrhosis increased by 3-fold and one with all 5 components had the risk of liver cirrhosis increased by 4.5-fold.
In summary, the large-scale study has clearly shown that metabolic syndrome is associated with liver cirrhosis in chronic hepatitis B. CUHK therefore recommends doctors taking care of chronic hepatitis B patients to proactively look for the evidence of metabolic syndrome and its components. As chronic hepatitis B patients with metabolic syndrome are more likely to harbor liver cirrhosis, diagnostic workup for cirrhosis is warranted in these cases because of the important therapeutic and surveillance implications.