Measuring Disease Severity, Quality of Life in Japanese Hepatitis Patients
As viral hepatitis is the most common blood-transmitted infection globally, assessing the toll of hepatitis and hepatitis-related conditions is critical.
Viral hepatitis can be sneaky, causing no symptoms in some people and debilitating ones in others–symptoms that can severely impact quality of life. In Japan, the most common infectious diseases are hepatitis B and C; roughly 3% of the population is infected with hepatitis C, which causes more than 30,000 deaths every year. In an effort to assess the health-related quality of life in Japanese people with hepatitis, a team of scientists from various hospitals and medical schools across Japan undertook a study to examine the health state utilities–global measurements of quality of life–in this population.
In 2012, the scientists offered self-administered questionnaires to outpatients at 34 medical facilities in Japan. The questionnaire, the EuroQol 5-Dimension, is a universally administered health-related quality of life measure that delves into 5 separate categories: mobility, ability to care for self, ability to engage in usual activities, pain and discomfort, and anxiety and depression. A total of 6331 responses were returned, with patients indicating which of 6 medical conditions they suffered from: chronic hepatitis, hepatic cirrhosis, hepatocellular carcinoma, viral carrier of hepatitis, fatty liver disease, and other conditions. Based on these responses, some of which indicated that patients had more than 1 condition, the study’s authors further refined the disease categories.
The subjects’ responses then were used to create a weighted health index that took into account data from the general population. In addition to the subjects’ answers, the study team received utility estimates from 3 hepatitis experts who had spent more than 15 years treating hepatitis patients. The experts relied on a literature review and their own experience as clinicians, and after engaging in multiple discussions to reach consensus the experts calculated health state utilities for a variety of hepatitis-related conditions.
It was necessary to rely on experts, the authors said, because patients with serious liver conditions or who had undergone liver transplantation might not have been able to answer the questions on their own. Using the data from patients as well as hepatitis experts, the scientists came up with utilities ranging from 0 to 1, with 1 representing no health complaints and 0 representing death.
Out of all the study participants, 1,322 had hepatitis B and 2,875 had hepatitis C. In patients with chronic hepatitis B who filled out the questionnaire, the utility of asymptomatic chronic hepatitis (ACH) was 0.904; the utility of chronic hepatitis (CH) was 0.868; the utility of compensated cirrhosis (CC) was 0.845; and the utility of decompensated cirrhosis (DC) was 0.722. Patients with chronic hepatitis C fared slightly worse, with the utilities of those same conditions as follows: 0.876 (ACH); 0.821 (CH); 0.737 (CC); and 0.671 (DC).
The hepatitis expert-reported utilities for other liver conditions were lower still. Patients with acute hepatitis B were determined to have utilities of 0.529 (acute hepatitis) and -0.111 (fulminant hepatitis). The latter utility is less than zero, and the authors acknowledged that this negative utility can occur when quality of life is assessed to be worse than death. For those with chronic hepatitis B and C, utilities were reported by the experts as 0.675 for hepatocellular carcinoma (HCC) stage I/II, 0.428 for HCC stage III/IV, and 0.651 for post-liver transplantation.
According to the authors, the study sheds light on the notably diminished quality of life faced by hepatitis B and C patients. The results were in line with similar studies, they said, although certain other studies yielded higher utilities. It’s possible, the authors theorized, that this was because all patients in those studies were outpatients and might not have had symptoms as severe.
The study’s limitations include the inability to get answers directly from some of the sickest patients and the fact that the quality of life questionnaire did not always capture fluctuations in symptoms. The authors also acknowledged that patients filling out the questionnaire might not always identify their own conditions accurately, leading to misclassification of disease.