Abstract
BACKGROUND: Hepatitis C is a serious public health problem in Los Angeles County. Only 30% of diagnosed persons are treated, and transmission is increasing. To further understand how social determinants impact hepatitis C, we assessed the association between neighborhood-level socioeconomic factors and the reported incidence of hepatitis C infection. METHODS: We conducted an ecological study of Los Angeles County residents aged 18 to 29 years with a reported positive hepatitis C viral nucleic acid test between July 2018 and June 2023. We used negative binomial regression to estimate reported hepatitis C incidence rate ratios by neighborhood with 95% confidence intervals (CI). A composite index score (range: 0-1) was created by ranking neighborhoods by combined social vulnerability and reported hepatitis C incidence. RESULTS: Among our final analytic sample of 7616, the Metro and South areas of Los Angeles County had the highest proportions of neighborhoods in the lowest quartile for composite index scores, with 50% of neighborhoods in each area in the lowest quartile, compared to 0%-19% in others. Among 10 Social Vulnerability Index factors, reported hepatitis C incidence was 9% higher (95% CI 3%-16%) in neighborhoods with more uninsured residents, 2% lower (95% CI 1%-3%) in neighborhoods with greater proportions of racial and ethnic minorities, and 5% higher (95% CI 1%-9%) in neighborhoods with more residents lacking access to vehicles. CONCLUSIONS: Lack of health insurance and access to vehicles correlated with increased reported hepatitis C incidence, while greater racial and ethnic diversity was associated with decreased reported hepatitis C incidence. Integrating social and epidemiologic data can help identify neighborhoods with characteristics associated with hepatitis C incidence.