Black, Hispanic, and Asian patients with hepatic encephalopathy (HE) are less likely to receive a prescription for secondary HE prophylaxis with rifaximin, and Black and Hispanic patients are more likely to have a higher cost per rifaximin prescription compared with White patients, according to study results published in the Journal of Hepatology.
Investigators reviewed a 20% random sample of Medicare/Medicare Part D patients with cirrhosis and HE from 2011 to 2019. Patients who were diagnosed with HE and had at least 180 days of documented follow-up were tracked until death, transplant, last documented follow-up, or the study end. For each patient, researchers noted race and ethnicity, as well as possible disease covariates such as age, region, referral to a gastroenterologist, and the underlying cause of cirrhosis.
Outcomes of the study included the difference in time to first rifaximin prescription, the cumulative use of rifaximin by person-years, and the cost of rifaximin, all according to patient race and ethnicity. Within the study, race and ethnicity categories were defined as Asian, Black, Hispanic, Other (multiple races, American Indian, unknown), and White.
Black patients were 30% less likely to receive a prescription for rifaximin compared with White patients (subdistribution hazard ratio, 0.70; 95% CI, 0.65-0.76). Asian and Hispanic patients were more likely than Black patients to receive a prescription for rifaximin, though still less likely than White patients. No difference was observed in patients categorized as Other compared with White patients.
After adjusting for possible covariates, Black patients had the longest time to rifaximin prescription and the lowest cumulative use of rifaximin. Asian patients had a delay to first rifaximin prescription but comparable overall rifaximin use comparable to that of White patients. Hispanic patients had no delay but slightly reduced cumulative rifaximin. There was no difference between patients who identified as Other and White patients.
The average financial burden of rifaximin per person per year was $760 for Hispanic patients, $514 for Black patients, and $481 for White patients, even though White patients had the highest number of refills per person-year.
Study limitations included unaccounted barriers to treatment, such as health literacy or the heterogeneity within Medicare Part D coverage plans. Additionally, the study population only included patients on Medicare and results may not be reflective of patients on Medicaid or private insurance.
Researchers believe a possible contributing factor for rifaximin disparities is Black and Hispanic patients’ reduced likelihood of receiving a referral to a gastroenterology specialist.
“Efforts are warranted to ensure appropriate rifaximin utilization, not simply by prescribing more but by reducing the cost of this medication, improving prescription coverage, and linking patients with cirrhosis to subspecialty consultation,” the study authors wrote.
Disclosure: One study author declared affiliations with biotech, pharmaceutical, and/or device companies. Pleases see the original reference for a full list of authors’ disclosures.
Tapper EB, Essien UR, Zhao Z, Ufere NN, Parikh ND. Racial and ethnic disparities in rifaximin use and subspecialty referrals for patients with hepatic encephalopathy in the United States. J Hepatol. Published online March 30, 2022. doi:10.1016/j.jhep.2022.02.010