Acute liver injury following acetaminophen overdose occurs in less than 10% of cases, but that risk is increased among alcoholics and those with chronic alcoholic liver disease.
Drs Geoffrey Nguyen and colleagues from Baltimore, USA assessed whether coexistent Hepatitis C virus infection potentiates the hepatotoxic effects of acetaminophen.
The researchers queried the Nationwide Inpatient Sample, a 20% sample of U.S. hospitals, to identify admissions for acetaminophen overdose using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes.
Outcomes were development of acute liver injury, in-hospital mortality, severe liver failure, and resource utilization.
<p><table border="0" width="200" cellspacing="2" cellpadding="2" align="right"><tr><td bgcolor="#666600"><img src="/graphics/spacer.gif" width="1" height="1" border="0" alt=""></td></tr><tr bgcolor="#cccc99"><td>The rate of acute liver injury was 7%</td></tr><tr><td bgcolor="#666600" class="source"><i>Hepatology</i></font><img src="/graphics/spacer.gif" width="1" height="1" border="0" alt=""></td></tr></table></p>
There were 42,781 admissions for acetaminophen overdose in the sample, yielding a national estimate of 210,436 acetaminophen overdose hospitalizations.
Hepatitis C prevalence increased from less than 1% to 2% between 1998 and 2005.
The team noted that the rate of acute liver injury was 7%.
After adjusting for confounders and excluding patients with cirrhosis, the risk of acute liver injury increased with Hepatitis C, nonalcoholic fatty liver disease, and alcoholic liver disease.
In addition, the team found that the risk of acute liver injury increased with malnutrition.
Hepatitis C was associated with greater risk of progression to severe liver failure.
The team observed that crude mortality was higher in patients with Hepatitis C compared to those without Hepatitis C.
Patients with acute liver injury had an overall mortality of 9%.
Length of stay was longer in patients with Hepatitis C.
The research team noted that admissions with coexistent Hepatitis C also incurred 2-fold higher hospital charges than those that did not.
Dr Nguyen and colleagues conclude, “Our retrospective analysis suggests that patients with Hepatitis C may be at increased risk of acute liver injury following acetaminophen overdose.”
“These findings warrant further confirmation in prospective studies.”