Noninvasive fibrosis scores, which are widely used to predict advanced fibrosis in people with nonalcoholic fatty liver disease (NAFLD), do not do a good job of picking up advanced fibrosis in patients with underlying diabetes, according to a new study.
Advanced fibrosis is associated with an increased risk of cirrhosis, end-stage liver disease, and liver failure. Underlying diabetes is a risk factor for both advanced fibrosis and death in patients with NAFLD.
While liver biopsy remains the gold standard for detecting advanced fibrosis, high costs and risks limit its use. Noninvasive scores such as the AST/ALT ratio; AST to platelet ratio index (APRI); fibrosis-4 (FIB-4) index; and NAFLD fibrosis score (NFS) have gained popularity in recent years, as they offer the compelling advantage of using easily and cheaply attained clinical and laboratory measures to assess likelihood of disease.
But their accuracy has come into question, particularly for people with diabetes.
In research published in the, Amandeep Singh, MD, and colleagues at the Cleveland Clinic looked at their center’s records for 1,157 patients with type 2 diabetes (65% women, 88% white, 85% with obesity) who had undergone a liver biopsy for suspected advanced fibrosis between 2000 and 2015. Biopsy results revealed that a third of the cohort (32%) was positive for advanced fibrosis.
The investigators then pulled patients’ laboratory results for AST, ALT, cholesterol, triglycerides, fasting glucose, hemoglobin A1c, bilirubin, albumin, platelet count, alkaline phosphatase, albumin, and lipid levels, all collected within a year of biopsy. After plugging these into the algorithms of four different scoring systems for advanced fibrosis, they compared results with results from the biopsies.
The scores of AST/ALT greater than 1.4, APRI of at least 1.5, NFS greater than 0.676, and FIB-4 index greater than 2.67 had high specificities of 84%, 97%, 70%, and 93%, respectively, but sensitivities of only 27%, 17%, 64%, and 44%. Even when the cutoff measures were tightened, the scoring systems still missed a lot of disease. This suggests, Dr. Singh and colleagues wrote, that “the presence of diabetes could decrease the predictive value of these scores to detect advanced disease in NAFLD patients.” Reliable noninvasive biomarkers are “urgently needed” for this patient population.
In an interview, Dr. Singh advised that clinicians continue to use current noninvasive scores in patients with diabetes – preferably the NFS – “until we have a better scoring system.” If clinicians suspect advanced fibrosis based on lab tests and clinical data, then “liver biopsy should be considered,” he said.
The investigators described among the limitations of their study its retrospective, single-center design, with patients who were mostly white and from one geographic region.
Dr. Singh and colleagues reported no conflicts of interest or outside funding for their study.
SOURCE: Singh A et al. J Clin Gastroenterol. 2020 Mar 11.