The combination of inflammatory bowel disease and fatty liver has been linked to worse outcomes for hospitalized patients, in a new study.
In research presented at the 2021 Crohn’s and Colitis Congress (abstract 3494541), a group from the University of California, Los Angeles reported that hospitalized patients with IBD and nonalcoholic fatty liver disease have longer stays and are twice as likely to be readmitted as those without the liver condition.
Rajiv Chhabra, MD, an associate professor at the University of Missouri Kansas City School of Medicine, who was not involved in the new work, said the study highlights “the pressing need to better understand the complex interaction between IBD and NAFLD, or hepatic steatosis. While previous research has reported that severity of IBD impacts the degree of hepatic steatosis, these researchers looked at the topic the other way around, to see how the presence of NAFLD impacts specific outcomes of IBD.”
NAFLD has been documented in as much as one-third of IBD patients (Inflamm Bowel Dis 2016;22[8]:1937-1944). Whereas the typical risk factors for NAFLD are obesity, type 2 diabetes mellitus and dyslipidemia, people with IBD seem to have other risk factors, said lead researcher Shaya Noorian, MD, a resident in internal medicine at the UCLA Medical Center.
“Medication hepatotoxicity, systemic inflammation related to IBD disease activity, history of IBD surgery and gut dysbiosis have all been linked to risk of NAFLD in the IBD population,” Dr. Noorian said.
To document the effect that NAFLD has on hospitalized IBD patients, Dr. Noorian and his coinvestigators analyzed data from the Nationwide Readmissions Database from 2016 to 2017. Their analysis included 11,197 hospitalized patients with Crohn’s disease and 6,120 patients with ulcerative colitis, approximately 2% of whom had NAFLD. Those with NAFLD were matched with IBD patients without the liver disorder on age, sex, type of bowel disease, metabolic syndrome and diabetes mellitus. The researchers also adjusted for the presence of obesity and dyslipidemia.
According to Dr. Noorian, multivariate analyses revealed that NAFLD doubled the risk for readmission in patients with Crohn’s disease (hazard ratio [HR], 1.98; 95% CI, 1.8-2.17; P<0.001) and ulcerative colitis (HR, 1.97; 95% CI, 1.67-2.32; P<0.001). Having NAFLD also was associated with longer average stays in the hospital for patients with Crohn’s disease (0.74 days longer; P<0.01) and ulcerative colitis (0.84 days longer) (P<0.01).
The average cost of care for patients with Crohn’s disease and NAFLD was $7,766 higher than for those with Crohn’s alone (P<0.01), and was $11,496 higher for people with ulcerative colitis and NAFLD than for their counterparts without NAFLD (P<0.01).
In contrast, NAFLD did not significantly increase the risk for death, Dr. Noorian’s team found.
Delineating which specific factors contribute to the development of NAFLD in IBD patients would be an important direction for future research, he said.
“Perhaps if reversible or preventable causes of NAFLD are identified, such factors can be targeted to improve outcomes in patients with coexisting NAFLD and IBD,” Dr. Noorian told Gastroenterology & Endoscopy News.
However, Dr. Chhabra urged that “caution should be used when interpreting results based off a database. There can be coding bias, misclassification bias, missed diagnoses, [issues with] external validity, all of which can limit the ability to generalize the results to a wider population.”
—David Wild
Drs. Chhabra and Noorian reported no relevant financial disclosures.
This article is from the August 2021 print issue.