Higher Mortality Rate Seen in Scottish Study of Patients Cured of Hepatitis C

A study of Scottish patients who had been treated and cured of hepatitis C found that the group had a higher mortality rate compared to the general population.

Researchers attributed the higher mortality among those studied to drug-related causes and liver cancer deaths. Results of the study, led by Hamish Innes, an epidemiologist at the the School of Health and Life Sciences at Glasgow Caledonian University, and chief analyst of Scotland’s national hepatitis C clinical database, were published in the Journal of Hepatology.

With the introduction in the last few years of new drugs that work faster and have higher cure rates, the number of people who had a previous hepatitis C infection and attained a sustained viral response (SVR) is expected to climb, noted study authors. When a patient achieves SVR after treatment it is an indication that the virus is no longer detected in the blood and is typically considered a cure.

The aim of the study was to evaluate a knowledge gap on the extent to which SVR is a cure to other aspects of the hepatitis C condition such as fibrosis of the liver or liver cancer.

“Although we know that SVR patients have lower mortality rates than non-SVR patients, we do not know how the mortality of this group compares to the general population,” the authors wrote in the article.

The study used a national database and identified patients in Scotland from 1996 to December 2010 who had attained SVR after receiving interferon-based antiviral therapy. The study involved a review of cause specific mortality data up to December of 2013.

Researchers calculated standardized mortality ratios to compare the frequency of mortality in patients who achieved SVR against the general population. They conducted a parallel analysis using Cox regression to identify modifiable patient characteristics that are associated with post-SVR mortality.

The study inclusion criteria required that patients have compensated liver disease and be treatment-naïve at the time of their treatment, according to the article. Patients were excluded from the study if they had HIV or hepatitis B coinfection.

Information such as date and cause of death were obtained through record linkage to the Scottish mortality register. Causes of death examined in the study included primary liver cancer, other liver disease, drug-related causes, external causes (mostly accident, homicide, or suicide), all non-liver cancers, diseases of the circulatory system and other causes.

The same causes of death were examined among records from the general population using a data set from the General Registry Office Scotland spanning from 1994 to 2014.

Out of 1824 patients who were followed an average of 5.2 years after treatment and subsequent SVR, a total of 78 deaths were reported in the study. Results indicated that all-cause mortality was 1.9 times more frequent for SVR patients than the general population, according to the journal article.

“In this large nationwide Scottish cohort, mortality in patients with a hepatitis C “cure” was higher than the general population,” concluded the authors. “The excess was mainly driven by death from liver cancer and death from drug-related causes.”

Liver cancer and drug related causes accounted for 66% of the total excess death among patients in the study, according to the article. Researchers noted that heavy alcohol use or injecting drugs were modifiable characteristics associated with increased mortality and that the roughly 33% patients without those behavioral markers experienced equivalent survival to the general population.

By contrast, another study out of Italy published earlier this year in the same journal found that patients treated successfully with interferon-based therapies have a similar life expectancy to the general population. The authors mention that the Italian study and another previous study do not support their recent finding of higher mortality among patients who achieved SVR compared to the general population, but they note that their study followed up a much larger, younger, and more inclusive group of patients who had achieved SVR.