By A.J. Hostetler

Wearable sensors that measure compounds found in sweat could help monitor the progression of a patient’s liver disease, according to research led by gastroenterologists at Virginia Commonwealth University and the Richmond VA Medical Center.

For three days, 32 patients with cirrhosis and 12 healthy people wore a noninvasive sweat sensor. The device, worn on the forearm, continuously monitored the levels of three compounds linked to liver inflammation that indicate liver scarring.

The pilot study, published by the journal Nature Digital Medicine, reveals how sweat-based monitoring might provide critical insights into disease progression, quality of life, and patient outcomes, potentially becoming another tool to assist in the care of individuals living with this chronic liver condition.

Liver disease is one of the world’s leading causes of death, accounting for 2 million deaths each year, according to the Global Burden of Disease study. Liver disease occurs when a person’s liver is chronically inflamed, often due to obesity, excessive alcohol use, viral hepatitis, or a combination. Over time, this inflammation can lead to severe scarring in the liver, known as cirrhosis, which disrupts liver function and can ultimately cause liver failure. To predict the course of their liver disease, patients face invasive, sporadic blood tests. However, researchers have been searching for noninvasive approaches that provide continuous monitoring.

The results of the study showed the sensor could distinguish the healthy control group from outpatient cirrhosis patients based on the measured biomarkers: interleukin-6, C-reactive protein and tumor necrosis factor-alpha.

“Many diseases such as cirrhosis are driven by chronic inflammation and clinically silent, i.e., without symptoms, until the end-stage,” said the study’s lead author, Brian Davis, M.D., an assistant professor with the VCU School of Medicine and the Richmond VA Medical Center. “This study is proof of concept that inflammation can be measured in sweat of patients with advanced liver disease. Future studies looking at ‘sweat signatures’ could lead to earlier diagnosis of infections, which are the main driver of hospitalization and death in cirrhosis.”

The sensor demonstrated a strong correlation between sweat and blood serum levels of inflammatory biomarkers, confirming its reliability. It also showed that inflammation levels among outpatients with cirrhosis peaked at the beginning of the evening and fell later at night and early morning before rising again. 

“This paves the way for using noninvasive continuous monitoring of patients with cirrhosis to hopefully better manage complications and prevent poor outcomes,” said the study’s corresponding author, Jasmohan Bajaj, M.D., of the VCU Stravitz-Sanyal Institute for Liver Disease and Metabolic Health and the Richmond VA Medical Center. “It offers clinicians a clearer picture of disease activity and enabling earlier interventions.”

Liver specialists are seeking non-invasive ways to test patients’ liver function, which would help patients avoid frequent, invasive and potentially painful blood tests or biopsies. Those tools offer only snapshot assessments, limiting their ability to provide a comprehensive picture of the disease. Although several companies have developed noninvasive tests using biomarkers, none has yet met the requirements needed for FDA regulatory approval.

Cirrhosis typically worsens from a scarred, inflamed organ to a stage where the patient experiences frequent infections, a decrease in cognitive function, bleeding and other symptoms that often lead to hospitalizations and even death.

For this study, the researchers used a sweat-sensing device called Sweat AWARE (A Wearable Awareness with Real-time Exposure), which transmits data in real time via Bluetooth to an individual’s smartphone or tablet and then to a server, allowing a physician to monitor the levels of the selected biomarkers. The device has already been shown to track systemic inflammation markers in sweat among patients with other gastrointestinal disorders such as inflammatory bowel disease.

The study enrolled 44 participants: 12 healthy volunteers and 32 patients with cirrhosis. Researchers collected data on sweat and blood levels of the biomarkers. They evaluated patients’ liver function, asked them to assess their quality of life, and tracked one-year transplant-free survival rates.

Notably, patients with active infections — such as urinary tract infections, bacteremia, and COVID-19 — displayed significantly higher sweat biomarker levels. This suggests that sweat monitoring could play a crucial role in early detection of infections and guiding timely interventions.

Bajaj notes this was a small, limited study and that larger, longer-term studies are needed to validate the intriguing findings, which may also offer insight for other diseases.

“Sweat sensors hold immense potential for managing not only cirrhosis but also other chronic inflammatory conditions,” added Bajaj. “Its application could transform the way we monitor and treat these diseases, offering a noninvasive, patient-centered solution.”

In addition to the VCU researchers, researchers from the University of Dallas and the sensor manufacturer, EnLisense, collaborated on the study.