Metabolic Syndrome Hikes Mortality in Hepatitis C

Metabolic Syndrome Hikes Mortality in Hepatitis C
By John Gever, Senior Editor, MedPage Today
Published: April 24, 2009
Reviewed by Robert Jasmer, MD; Associate Clinical Professor of Medicine, University of California, San Francisco Earn CME/CE credit
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WHEELING, W.Va., April 24 -- Patients with hepatitis C infection appear more likely to die from the condition if they also suffer from one or more components of metabolic syndrome, a researcher said.

Excess body weight and hypertension both significantly heightened the risk of liver-related mortality in hepatitis C patients, according to data from the third National Health and Nutrition Examination Survey (NHANES) series, reported Zobair Younossi, M.D., of Inova Health System in Falls Church, Va.

Those two factors as well as the third component of metabolic syndrome -- type 2 diabetes -- also made death from all causes more likely during the study period, said Dr. Younossi.

He spoke with MedPage Today by telephone from Copenhagen, Denmark, in advance of his formal presentation of the data at the annual meeting of the European Association for the Study of the Liver.
Action Points

■Explain to interested patients that progression of hepatitis C is influenced by a variety of factors and comorbid conditions,

■Explain that the study did not address the effects of treatment of hypertension, obesity, or diabetes or insulin resistance on survival of HCV-infected patients.
Earlier research had found numerous factors associated with more rapid progression of hepatitis C infection, Dr. Younossi said, including components of metabolic syndrome individually and, perhaps, together.

To explore the relationship, Dr. Younossi and his colleagues analyzed data from NHANES III, conducted from 1988 to 1994. The data also include mortality follow-up information through 2000, a median of 8.5 years.

Out of more than 31,000 NHANES participants, the researchers identified 264 with hepatitis C and 13,004 without liver disease who could serve as controls.

Only survey participants with complete records for numerous clinical parameters were eligible for inclusion in the study.

The researchers found that hepatitis C cases were more likely than controls to have insulin resistance, as defined by a HOMA score of at least 3 -- 37.4% of cases versus 22.5% of controls (P=0.02) -- and were dramatically more likely to smoke (64.0% versus 26.6%,P<0.001).

A diagnosis of type 2 diabetes was moderately more common among cases as well.

On the other hand, the hepatitis C cases showed somewhat lower rates of hypertension, obesity, and metabolic syndrome.

But the 51 deaths among the hepatitis C cases were disproportionately concentrated in those with the latter conditions.

With multivariate analysis, the researchers calculated the following adjusted hazard ratios for all-cause mortality in hepatitis C cases, compared with controls:

•Type 2 diabetes: HR 2.14 (95% CI 2.11 to 2.16)
•Higher body mass index: HR 1.05 (95% 1.05 to 1.06)
•Hypertension: HR 1.41 (95% CI 1.39 to 1.42)

For liver-related death only, two of these three factors were also strong predictors in the hepatitis C cases:

•Higher BMI: HR 1.28 (95% CI 1.27 to 1.28)
•Hypertension: HR 3.75 (95% CI 3.65 to 3.85)

Dr. Younossi said that patients with any of the components of metabolic syndrome should be treated for them, and those with hepatitis C are no exception.

But he cautioned that only a prospective trial could confirm that successful treatment of metabolic syndrome or its components would improve survival in hepatitis C patients.

He also noted several limitations of the study: lack of liver biopsy or genotype data for hepatitis C cases, a relatively short follow-up, and the potential underestimation of hepatitis C prevalence in NHANES data.

No external funding for the study was reported.

Dr. Younossi reported no potential conflicts of interest.

Primary source: European Association for the Study of the Liver
Source reference:
Rafiq, N. et al "Type 2 diabetes, obesity and hypertension are associated with mortality in hepatitis C patients" EASL 2009; Abstract 324.