Editorial Commentary: Determining the Effect of Hepatitis C on Mortality: Sorting the Signal From the Noise

Abstract

Pinchoff et al examined surveillance data for hepatitis C reporting, and compared it to cause-of-death data obtained from death certificates from 2000 to 2011 in New York City (NYC). Theyevaluated the effect of hepatitis C on age of death and cause of death (COD), as well as the effect of coinfection with human immunodeficiency virus (HIV) compared with the population without these diseases. This was a well-designed study taking advantage of NYC having several robust disease surveillance registries that were able to be cross-matched and then compared with mortality data. By doing the study in NYC, they were able to evaluate a large, well-defined, and diverse population with a particularly high incidence of this disease [5]. This study adds to the literature as it helps to delineate the natural history of hepatitis C in the real world. The authors were able to convincingly demonstrate an increased risk of premature mortality (age <65) in patients infected with HCV, stressing the importance of early identification and potential treatment of this disease. The study also attempted to further evaluate the cause of death in this population from a review of death certificate data. It is very important to understand when and how people are being diagnosed with the disease and, ultimately, their specific cause of death. There are, however, some weaknesses in the study that need to be discussed. Unlike a true cohort, this study only captured people who died in NYC. Patients who were diagnosed and treated in NYC would not be included in the COD analysis if they were to die outside the city limits. Although the study implies that earlier diagnosis and treatment would likely decrease premature mortality, the study was not able to evaluate the subset of people who were treated for hepatitis C, and with what regimen. Overall, the study does an excellent job demonstrating the associated mortality with HCV, but causation is much more difficult to prove. Last, the utilization of death certif