Factors influencing hepatitis C treatment initiation in a high-prevalence Brazilian state.

Hepatitis C virus infection remains a leading cause of chronic liver disease worldwide, affecting more than 70 million people, many of whom remain undiagnosed or untreated. In Brazil, Rio Grande do Sul State has the highest hepatitis C detection rate, underscoring the need for coordinated strategies to eliminate it by 2030. Underdiagnosis and barriers to treatment initiation persist despite the availability of highly effective antiviral therapies. This study aimed to estimate the proportion of diagnosed individuals who initiated treatment and to find factors associated with non-initiation of treatment. A retrospective cohort included all hepatitis C cases that had been diagnosed in 2022-2023 and reported in the Brazilian Information System for Notifiable Diseases (SINAN). Treatment initiation was verified in the Logistics Control System for Medications for Viral Hepatitis (SICLOM-HV). Probabilistic record linkage was performed to integrate both databases and to assess factors associated with non-initiation of treatment. Among 2,671 diagnosed individuals, 64.9% started treatment, with a median of 104 days between diagnosis and initiation. Multivariable analysis showed lower initiation among Black individuals than in White ones (adjusted OR = 1.41; 95%CI: 1.02-1.93) and among those aged 0-39 than in those aged 50-59 years (adjusted OR = 0.68; 95%CI: 0.49-0.96). Regional differences, HIV coinfection, and clinical variables also affected initiation. Treatment coverage in Rio Grande do Sul State remains below elimination targets. Persistent disparities by race, region, and coinfection highlight the need for targeted strategies to ensure equitable hepatitis C care and accelerate elimination efforts.