Successful hepatitis C virus (HCV) therapy reduces the risk of developing type 2 diabetes by approximately a fifth, according to results of a large US study published in the Journal of Viral Hepatitis. People who attained a sustained virological response (SVR) were 21% less likely to develop diabetes than people who did not respond to treatment. In people who did not attain an SVR to HCV therapy, other risk factors for the development of type 2 diabetes were race, high body mass index (BMI) and baseline cirrhosis.
“In a large US cohort of patients treated for HCV, we found that achievement of SVR independently reduced the risk of T2D [type 2 diabetes],” comment the researchers. “The SVR effect was consistent across demographic characteristics and clinical conditions at the time of treatment.”
Type 2 diabetes is a well-known complication of HCV infection. The impact of successful HCV therapy on the risk of type 2 diabetes is unclear.
- sustained virological response (SVR)
Undetectable hepatitis C RNA after treatment has come to an end. Usually SVR refers to RNA remaining undetectable for 24 weeks (six months) after ending treatment and is considered to be a cure. SVR4 and SVR12 refer to RNA remaining undetectable for 4 and 12 weeks respectively.
Investigators from the US compared incidence of type 2 diabetes according to HCV treatment outcomes in patients enrolled in the Chronic Hepatitis Cohort Study. This is a geographically and racially diverse cohort involving patients in four large US health systems.
The study population consisted of 5127 people who received treatment and care between 2006 and 2015. Regimens of all-oral direct-acting antivirals (DAAs) were taken by 44% of participants.
Most of the participants (60%) were male, 72% were white and the average age was 59 years.
Approximately three-quarters of participants (73%) attained an SVR. A total of 530 incident cases of type 2 diabetes were observed after completion of treatment and assessment of 12-week post-treatment virological response, during a mean follow-up period of 3.7 years.
After taking into account other factors, an SVR was shown to reduce the risk of type 2 diabetes by 21% (aHR = 0.79; 95% CI, 0.65-0.96, p = 0.02). There was no interaction between SVR and other diabetes risk factors, thus showing that attainment of SVR had an independent effect on diabetes incidence.
Several baseline characteristics were associated with increased diabetes risk in people who did not have a successful response to HCV therapy. Individuals with a very high BMI (30 kg/m2 and over) were almost four times more likely to develop diabetes compared to individuals with BMI below 25 kg/m2 (aHR = 3.6; 95% CI, 2.2-5.95).
Race was also a significant risk factor, with African American, Asian American, American Indian and Pacific Islanders all having a significantly higher risk of diabetes compared to white people.
The risk of developing diabetes also increased with age and was over twofold higher for people aged in their 60s compared to those aged 40 years or younger.
Presence of baseline cirrhosis also significantly increased diabetes risk (aHR = 1.47; 95% CI, 1.17-1.84).
“Among a geographically- and racially-diverse cohort of more than 5,000 patients from US healthcare systems, successful HCV treatment was associated with significant reductions in the incidence of T2D,” conclude the authors. “African American and Asian, American Indian, or Pacific Islander race, as well as the presence of cirrhosis, appear to increase the risk of developing T2D without a successful response to treatment. Therefore, patients with these risk factors should be monitored closely for T2D prevention and care.”