Disparities in Initiation of Direct-Acting Antiviral Agents for Hepatitis C Virus Infection in an Insured Population

Abstract

Objectives: The cost of direct-acting antiviral agents (DAAs) for hepatitis C virus (HCV) infection may contribute to treatment disparities. However, few data exist on factors associated with DAA initiation.

Methods: We conducted a retrospective cohort study of HCV-infected Kaiser Permanente Northern California members aged ≥18 during October 2014 to December 2016, using Poisson regression models to evaluate demographic, behavioral, and clinical factors associated with DAA initiation.

Results: Of 14 790 HCV-infected patients aged ≥18 (median age, 60; interquartile range, 53-64), 6148 (42%) initiated DAAs. DAA initiation was less likely among patients who were non-Hispanic black (adjusted rate ratio [aRR] = 0.7; 95% confidence interval [CI], 0.7-0.8), Hispanic (aRR = 0.8; 95% CI, 0.7-0.9), and of other minority races/ethnicities (aRR = 0.9; 95% CI, 0.8-1.0) than among non-Hispanic white people and among those with lowest compared with highest neighborhood deprivation index (ie, a marker of socioeconomic status) (aRR = 0.8; 95% CI, 0.7-0.8). Having maximum annual out-of-pocket health care costs >$3000 compared with ≤$3000 (aRR = 0.9; 95% CI, 0.8-0.9) and having Medicare (aRR = 0.8; 95% CI, 0.8-0.9) or Medicaid (aRR = 0.7; 95% CI, 0.6-0.8) compared with private health insurance were associated with a lower likelihood of DAA initiation. Behavioral factors (eg, drug abuse diagnoses, alcohol use, and smoking) were also significantly associated with a lower likelihood of DAA initiation (all P < .001). Clinical factors associated with a higher likelihood of DAA initiation were advanced liver fibrosis, HCV genotype 1, previous HCV treatment (all P < .001), and HIV infection ( P = .007).

Conclusions: Racial/ethnic and socioeconomic disparities exist in DAA initiation. Substance use may also influence patient or provider decision making about DAA initiation. Strategies are needed to ensure equitable access to DAAs, even in insured populations.

Keywords: health care delivery; hepatitis; racial disparities; substance abuse; treatment.

Figure 1.

Identification of hepatitis C virus (HCV)-infected adults aged ≥18 who were eligible to receive direct-acting antiviral agents, Kaiser Permanente Northern California (KPNC), October 2014–December 2016.

Figure 2.

Cumulative incidence of direct-acting antiviral agent (DAA) initiation among hepatitis C virus (HCV)-infected adults aged ≥18 (n = 14 790), by year, stratified by (A) race/ethnicity and (B) neighborhood deprivation index, Kaiser Permanente Northern California, October 2014–December 2016. The neighborhood deprivation index is a measure of socioeconomic status that incorporates census tract–level measures of education, income and poverty, employment, housing, and occupation. The highest quartile (4) indicates the greatest neighborhood deprivation, and the lowest quartile (1) indicates the lowest neighborhood deprivation. Differences in DAA initiation by race/ethnicity and neighborhood deprivation index were significant (both P < .001 by log-rank test).