Black patients hospitalized with nonalcoholic fatty liver disease are significantly more likely to die in the hospital or suffer acute liver disease than white patients hospitalized with NAFLD, according to a retrospective analysis presented at the 2021 virtual Digestive Disease Week (poster Sa346). Black patients also experienced longer hospital stays than white patients, and came from families with more modest incomes on average.
Geneticists have established that Black and white people are less likely to have a genetic predisposition to NAFLD than Native Americans, Hispanics or Asians. Despite this similarity, research has suggested that Black patients with NAFLD face different prognoses than whites with the condition. The new study aimed to document whether there were indeed health outcome differences between the two groups in hospital settings.
“There is definitely a difference in clinical outcomes between African Americans and whites in my anecdotal experience, so I decided to look into this question,” said David U. Lee, MD, who led the research. Dr. Lee, who completed this research as a fellow at Tufts University, in Boston.
Dr. Lee and his colleagues analyzed seven years of data (2011-2017) from the National Inpatient Sample, a data set collected by the U.S. government to enable longitudinal research of health outcomes in hospitals across the country. They examined the health records of approximately 50,000 adults with NAFLD (47,503 white and 2,816 Black patients) hospitalized during this period, to determine whether the health status of these patients was broadly similar or diverged appreciably. These health indicators ranged from in-hospital mortality to having other concomitant conditions, such as ascites or cirrhosis.
The researchers excluded people younger than 18 years of age from the analysis, as well as those with other liver diseases such as infection with either the hepatitis B or C virus.
Relatively few NAFLD patients of any race died in the hospital, although Black patients died at a significantly higher rate than white patients (5.58% vs. 4.64%). More than 10% of Black patients experienced acute liver failure in the hospital, which was not the case as frequently for white patients (13.5% vs. 7.92%), Dr. Lee’s group found. However, Black patients were less likely to experience cirrhosis (45.8% vs. 64.9%), ascites (22.7% vs. 32.4%) or variceal bleeding (1.85% vs. 4.38%).
Compared with white patients, Black patients were more likely to have modest incomes and to be insured through Medicaid.
Dr. Lee acknowledged that these data are observational, and not definitive proof of any link between genetics, economics and NAFLD outcomes. “It’s always a pivotal step to make these observational studies,” he said, because they can serve as a conduit to more definitive research later.
Nicole Rich, MD, a gastroenterologist at UT Southwestern Medical Center, in Dallas, who studies racial, ethnic and sex disparities in liver disease, called the latest results “hypothesis-generating,” but noted that data from administrative databases such as the National Inpatient Sample can be fraught. On one hand, the sheer numbers of patients are rarely seen in multicenter cohort studies. On the other hand, these data sets lack granularity, such as details on liver function and other comorbidities, making it difficult to reach firm conclusions.
More work is needed to tease out the relative contribution of modifiable and nonmodifiable factors to the severity of NAFLD, she said, from genetics, which cannot be changed, to lifestyle and environment, over which patients have some control. Dr. Rich hypothesized that modifiable neighborhood-level factors, such as limited access to healthy food, may contribute to disparities in the incidence and outcomes of NAFLD. However, more detailed data on neighborhood food patterns—as a complement to the national data—would be necessary to test this premise.
—Marcus Banks
This article is from the August 2021 print issue.