Original Study: Bajaj JS et al, JAMA Network Open, 2024;7(1):e2353965

Study Type: Retrospective cohort study

Distinguishing dementia from hepatic encephalopathy (HE) isn’t always straightforward, especially when cirrhosis hasn’t been diagnosed. This national VA study asked how often liver disease might be an unrecognized, and potentially reversible, contributor to cognitive decline in older veterans labeled with dementia.

Researchers analyzed records from 177,422 veterans with a dementia diagnosis but no prior cirrhosis diagnosis. Using the Fibrosis-4 (FIB-4) index (age, aspartate/alanine aminotransferase, and platelet count), they looked for signs of advanced liver disease. About 10% had FIB-4 scores over 2.67 (suggesting advanced fibrosis) and 5% had scores over 3.25 (suggesting cirrhosis). Among those in the latter group, more than 95% had imaging or lab evidence consistent with cirrhosis. High FIB-4 scores were more common in non-White, Hispanic, urban-dwelling veterans and in those with alcohol use disorder, hepatitis B or C, or chronic kidney disease. 

The study did not report how many of these veterans actually had clinical HE, although prior literature shows that this condition occurs in at least 30%–40% of patients with cirrhosis (Vilstrup H et al, Hepatology 2014;60(2):715–735).

CARLAT TAKE
When evaluating cognitive decline, it’s worth remembering that not every “dementia” is neurodegenerative. This VA study found that a meaningful subset of older adults labeled with dementia had FIB-4 scores suggestive of advanced fibrosis (the stage just before cirrhosis) or cirrhosis, and many in the highest-risk group had corroborating lab or imaging findings. Advanced fibrosis or cirrhosis doesn’t necessarily mean a patient has HE, but HE is common in this stage of liver disease and can contribute to cognitive symptoms. Because HE can mimic dementia and is at least partly reversible, running a quick FIB-4 check can be worthwhile, especially in patients with alcohol use, viral hepatitis, or unexplained lab abnormalities. For a FIB-4 calculator, see: www.tinyurl.com/fdfe5nn. It’s a low-effort screen that might uncover a reversible cause of cognitive decline.