Early Screening Technology Helps Reduce Risk of Liver Disease

Thirty percent of Americans will experience some degree of non-alcoholic fatty liver disease (NAFLD), the most common type of liver disease in the Western world and one that has been linked to diabetes, obesity, insulin resistance, and other metabolic risk factors.

Until recently, liver biopsy has been the gold standard for identifying these two critical endpoints but has well known limitations including invasiveness, rare but potentially life-threatening complications, poor acceptability, sampling variability, and cost. Biopsy also carries potential side effects that are infrequent but clinically important, and is not considered completely accurate. Furthermore, due to the epidemic proportion of individuals with NAFLD worldwide, liver biopsy evaluation is impractical and carries a significant resource and cost burden, which makes it inadequate for patient assessment on a large scale.

For these reasons, an innovative non-invasive assessment for the diagnosis of nonalcoholic steatohepatitis (NASH)—the more severe form of NAFLD—and liver fibrosis has become available at a critical time for the nation’s health.

Early Evaluation Is Critical—and Easy
The 2019 Standards of Medical Care in Diabetes issued by the ADA recommend that patients with type 2 diabetes or pre-diabetes and elevated liver enzymes or fatty liver should be evaluated for the presence of NASH and liver fibrosis. Patients who would benefit most from early evaluation include those with components of the metabolic syndrome.

A growing number of healthcare providers have begun to adopt non-invasive screening methods that can detect NAFLD in the absence of indications or warning signs. These innovative and painless approaches can be performed in the doctor’s office as part of an annual exam, and is covered by Medicare, Medicaid, and other insurance plans.

A 10-minute screening offers quick insight into liver health—measuring liver fat content and liver stiffness (associated with fibrosis and cirrhosis)—while potentially eliminating the need for a liver biopsy and/or further testing. Test scores provide information the physician can use to make a referral to a specialist or recommend additional assessments. In fact, a yearly NAFLD screening is likely to become standard practice similar to a mammography or A1C blood sugar testing.

FibroScan, for example, is a unique technology that can be used to quantitatively estimate the amount of liver stiffness and fat, potentially saving time and resources for people who don’t need to undergo additional assessment. These quantitative measurements with FibroScan can be used to track changes in liver health over time and can potentially be combined with blood biomarkers to cost effectively create more sensitive and specific scores for monitoring.

Additionally, FibroScan is a portable device and its rapid, non-invasive exam can be operated by a medical assistant and interpreted by the healthcare professional at the point of care delivery, making it a valuable accompaniment for managing patients, regardless of where they receive care.

The Technology Behind Screening Methods
FibroScan assesses liver stiffness using a patented technique called vibration-controlled transient elastography (VCTE). VCTE is recognized worldwide as the original and most extensively studied technology for liver stiffness assessment. This technique has been included in over 2,000 peer-reviewed publications and is across most clinical practice guidelines.

In the VCTE assessment, a shear wave is mechanically induced. The speed of the shear wave is measured with pulse echo ultrasound. Scientific validation establishes that high shear wave speed correlates to high liver stiffness.

To complement the VCTE assessment, FibroScan estimates the fat content in the liver using a patented technique called controlled attenuation parameter (CAP). In the CAP technique, the ultrasound attenuation rate is measured simultaneously in the same 3cm3 region as the assessment of liver stiffness. This approach minimizes the operator’s effort while ensuring the assessment is performed in the same location in the liver parenchyma, thus allowing for consistency of measurements over time.

Many of the compounds in advanced clinical trials for NAFLD include FibroScan in their risk stratification strategies. One approach is three-tiered:

1. Rules out/in advanced fibrosis FIB-4 or NAFLD fibrosis and searches for other causes of liver disease with a blood sample
2. Performs FibroScan screening to rule out/in advanced fibrosis
3. MRE/biopsy

Value in Identifying Asymptomatic Patients
An interim look at an ongoing study of 10,000 patients with no history of liver disease was conducted in community-based endoscopy centers by the Florida Research Institute (FRI). Only 43 percent of patients evaluated had what is considered normal livers based on a FibroScan assessment alone, while the remainder had some form of liver abnormality, ranging from elevated liver fat to liver fibrosis, including 13 percent suspected of having undiagnosed liver fibrosis or cirrhosis. While further workup is recommended to confirm the extent of liver disease in these patients, this analysis of the first 367 patients suggests a significant rate of undiagnosed NAFLD in the population studied.

These results underscore the importance of identifying asymptomatic patients who may be at risk for advancing disease for earlier intervention, while the increasing prevalence of disease shows the importance of regular assessment.

With innovative non-invasive technologies, NAFLD is reversible if caught in the early stages and accompanied by lifestyle changes. What’s more, simple screening and early detection can help to prevent more serious conditions, such as end-stage liver disease or liver cancer.