How to find NASH
Both the American Diabetes Association and the European Association for the Study of Diabetes call for routine screening of patients with T2D, starting with a check of liver enzymes, such as ALT, but no clear consensus exists for the specifics of screening beyond that. Dr. Mantzoros, Dr. Cusi, and other experts agree that the scheme for assessing liver disease in patients with T2D starts with regular monitoring of elevations in liver enzymes including ALT. Next is noninvasive ultrasound assessment of the extent of liver fibrosis inferred from the organ’s stiffness using transient elastography. Another frequently cited initial screening tool is the Fibrosis-4 (FIB-4) score, which incorporates a patient’s age, platelet count, and levels of ALT and a second liver enzyme, AST.
“There is more consensus about FIB-4 and then elastography, but some people use tests other than FIB-4. Unfortunately there is no perfect diagnostic test today. A top priority is to define the best diagnostic test,” said Dr. Mantzoros, who is leading an effort to try to refine screening using artificial intelligence.
“FIB-4 is simple, easy, and well validated,” commented Dr. Cusi during the WCIRDC last December. “FIB-4 and elastography should get you pretty close” to identifying patients with T2D and significant liver disease.
But in a recent editorial, Dr. Cusi agreed on the need for “more reliable tests for the diagnosis of NASH and advanced fibrosis in patients with T2D. Significant work is being done in the field to validate novel and more sophisticated fibrosis biomarkers. Future studies will help us enter a new era of precision medicine where biomarkers will identify and target therapy to those with more active disease at risk for cirrhosis,” he wrote.
“The ultimate goal is to diagnose fibrosis at an early stage to prevent people from developing cirrhosis,” Dr. Cusi said in a recent written statement. “We’re trying to identify these problems before they’re unfixable. Once someone has cirrhosis, there isn’t a whole lot you can do.”
Pioglitazone remains the best-documented treatment
Perhaps some of the inertia in diagnosing NAFLD, NASH, and liver fibrosis in patients with T2D is dissatisfaction with current treatment options, although several proven options exist, notably weight loss and diet, and thiazolidinedione (TZD) pioglitazone. But weight loss and diet pose issues for patient compliance and durability of the intervention, and many clinicians consider pioglitazone flawed by its potential adverse effects.
“When we don’t have an established treatment for something, we tend to not measure it or go after it. That’s been true of liver disease” in patients with T2D, said Yehuda Handelsman, MD, an endocrinologist and diabetes specialist who is medical director of the Metabolic Institute of America in Tarzana, Calif., during the WCIRDC.
Treatment with pioglitazone has resolved NASH in about a third of patients compared with placebo, prevented fibrosis progression, and cut cardiovascular disease events, noted Dr. Cusi during the WCIRDC.
“Pioglitazone is used in only 8% of patients with T2D, or less, but we need to use it more often because of its proven efficacy in patients with T2D and NASH” said Dr. Mantzoros. “The problem is that pioglitazone has side effects, including weight gain and fluid retention, that makes it less attractive unless one thinks about the diagnosis of NASH.”
Others highlight that the adverse effects of pioglitazone have been either misunderstood, or can be effectively minimized with careful dosing.
Dr. Ralph A. DeFronzo
“The data with the TZDs are much stronger than the data from anything else. TZDs have gotten a bad name because they also work in the kidney and enhance fluid reabsorption. We use modest dosages of pioglitazone, 15 mg or 30 mg a day, to avoid excess fluid retention,” Ralph A. DeFronzo, MD, chief of the diabetes division and professor of medicine at the University of Texas Health Science Center, San Antonio, said during the WCIRDC. “The best drug for NASH is pioglitazone. No other drug beats it” based on current data, Dr. DeFronzo asserted.
Other strategies include the potential to pair pioglitazone with other interventions that can blunt a weight-gain effect. One intriguing combination would combine pioglitazone with a GLP-1 receptor agonist, a drug class that can produce significant weight loss. Results from a phase 2 study showed promise for semaglutide (Rybelsus) in treating patients with NASH.