BACKGROUND: American Indian/Alaska Native (AI/AN) populations have the highest hepatitis C virus (HCV)-related mortality rate in the United States; disparity in Washington State is unknown. Accurate estimates of HCV mortality are important for resource allocation for screening and treatment. We assessed health disparities in HCV-associated mortality among AI/AN in Washington residents from 2009-2014.
METHODS: We corrected AI/AN race in death certificates by using record linkage with the Northwest Tribal Registry (NTR) – a listing of AI/AN patients treated at Indian Health Service, Tribal, and Urban Indian Health clinics in Idaho, Oregon, and Washington. AI/AN race was classified as a record that was AI/AN on a Washington death certificate or had a match with NTR. HCV-associated deaths were classified by using International Classification of Diseases, Tenth Revision codes in the underlying and contributing cause of death fields. We calculated five-year aggregate age-adjusted HCV and HCV-associated mortality rates for AI/AN and non-Hispanic whites (NHW) by using National Center for Health Statistics bridged race estimates standardized to the U.S. Census Bureau 2000 standard population.
RESULTS: The 2009–2014 age-adjusted HCV mortality rate was 9.2/100,000 population (95% confidence interval [CI]: 7.1, 12.2) for AI/AN and 2.7/100,000 (95% CI: 2.5, 2.9) for NHW (rate ratio [RR]: 3.4; 95% CI: 2.7, 4.3). The 2009–2014 age-adjusted HCV-associated mortality rate was 16.4/100,000 population (95% CI: 13.6, 20.1) for AI/AN in Washington, compared with 4.4 (95% CI: 4.1, 4.6) for NHW in Washington (RR: 3.8; 95% CI: 3.2, 4.5).
CONCLUSIONS: Washington AI/AN residents have a higher rate of HCV-associated mortality, compared with NHWs. The burden of HCV-associated mortality among AI/AN in Washington highlights the need to expand AI/AN access to HCV screening and treatment.