A significant increase in serious liver disease among heavy drinkers has been documented in a new study conducted by researchers at Keck Medicine of USC. This alarming trend suggests that the prevalence of advanced liver scarring has more than doubled among those who consume high levels of alcohol, even in the absence of increased drinking. The findings were published in the journal Clinical Gastroenterology and Hepatology on March 15, 2024.
Over the past two decades, the percentage of heavy drinkers exhibiting advanced liver fibrosis rose from 1.8% to 4.3%. For women, heavy drinking is defined as more than 1.5 drinks per night on average, while for men, it is more than 2 drinks. Dr. Brian P. Lee, a liver transplant specialist and lead author of the study, expressed his astonishment at the findings, noting that the risk of developing serious liver conditions has nearly tripled.
The study analyzed health data from over 44,000 adults surveyed between 1999 and 2020, as part of the National Health and Nutrition Examination Survey (NHANES). Among those surveyed, 2,474 were classified as heavy drinkers according to the National Institute on Alcohol Abuse and Alcoholism’s definitions. The analysis revealed a more than twofold increase in significant liver fibrosis, a condition where healthy liver tissue is replaced with stiff fibrous tissue, potentially leading to liver failure or cancer if left untreated.
In stark contrast, the incidence of liver disease among non-heavy drinkers saw a minor increase from 0.8% to 1.4% over the same period. This rise in liver damage is particularly troubling, as many individuals remain unaware of their condition until it has advanced significantly. “Liver disease is silent,” Dr. Lee pointed out. “Most people won’t have any symptoms, even if they have advanced liver scarring.”
Shifts in demographics and health conditions among heavy drinkers have contributed to the increased risk. The rate of metabolic syndrome, which encompasses conditions such as obesity, diabetes, and high blood pressure, rose from 26% to nearly 38% among this group. Additionally, heavy drinkers are now more likely to be women, individuals over the age of 45, and those living in poverty.
Dr. Sammy Saab, medical director of the Pfleger Liver Institute at UCLA, who was not involved in the study, suggested that changes in drinking habits might also be influencing these trends. He raised questions about whether consumers are gravitating towards stronger alcoholic beverages or changing their drinking patterns, such as consuming alcohol without food, which can increase absorption.
Cultural shifts may also play a role. Dr. Saab noted that advancements in transportation options, like ridesharing services, have removed some of the barriers to heavy drinking that existed in the past.
The current definition of heavy drinking in the United States may not adequately reflect evolving health standards, Dr. Lee argued. In Canada, for instance, the recommendation is now limited to no more than two drinks per week to minimize health risks. In contrast, the U.S. defines heavy drinking as eight drinks or more per week for women and 15 drinks or more for men. Dr. Lee emphasized that liver disease can develop at lower consumption levels than those currently recognized in U.S. guidelines.
The implications of these findings are significant, highlighting the urgent need to reassess long-held assumptions about alcohol-related liver disease. Dr. Lee hopes that the research will lead to improved screening methods for early detection of liver conditions. Dr. Saab endorsed the study’s conclusions, describing it as a call to action for researchers and healthcare professionals to better understand the increase in alcohol-associated liver disease and to devise strategies for prevention.