Occupational class and risk of hepatitis B and C viral infections: A case-control study-based data from a nationwide hospital group in Japan.

Background: Occupational class, a proxy for socio-economic status, is a known factor for health disparities. However, no study has reported the association between occupational class and the risk of viral hepatitis B and C (HBV/HCV) infections. We investigated the effects of occupational class on the prevalence of HBV/HCV infections.
Methods: This is an unmatched hospital-based case-control study that included 12,101 patients who were diagnosed with HBV infection (ICD-10, B16.0, B16.1, B16.2, B16.9, B17.0, B18.0, B18.1) or HCV infection (ICD-10, B17.1, B18.2) and 698,168 controls (those with non-HBV/HCV-related diseases) aged ≥ 20 years who were initially hospitalized between 2005 and 2019. Patients were categorized according to occupational class (blue-collar, service, professional, and manager) and industrial sector (blue-collar, service, and white-collar). Managers in the blue-collar industry were set as the reference group, and the odds ratios (ORs) for the risk of HBV and HCV infections were calculated.
Results: Occupational class was significantly associated with only HCV infection risk. Professionals in all industrial sectors showed the lowest risk for HCV (OR (95% confidence intervals [CIs]) = 0.69 [0.58-0.82] in the blue-collar industry, 0.52 [0.38-0.73] in the service industry, and 0.60 [0.52-0.70] in the white-collar industry). Further, after adjusting for sex, age, and region of admitting hospital, all occupational classes in the white-collar industry showed lower risks of HCV than those in the other industries (ORs= 0.58 [0.47-0.71] in blue-collar workers, 0.74 [0.64-0.84] in service workers, 0.60 [0.52-0.70] in professionals, and 0.81 [0.64-1.02] in managers in white-collar industry).
Conclusions: Occupational class was closely associated with HCV infection risk only. Considering that blue-collar workers in the white-collar industry also showed a low risk, adequate measures should be taken against hepatitis, possibly because of the screening tests and cure implemented in that population.
Competing Interests: Conflict of interest None declared.
(Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)