Moderate alcohol consumption is associated with an increased risk for advanced fibrosis in nonalcoholic fatty liver disease, with the risk highest among those with type 2 diabetes, according to study data.
“Moderate alcohol consumption, corresponding to between six and 12 glasses of wine per week, is likely to increase the risk for development of severe liver damage (cirrhosis) and future liver failure in subjects with fatty liver associated with metabolic syndrome,” Stergios Kechagias, MD, PhD, professor of internal medicine in the department of health, medicine and caring sciences at Linköping University in Sweden. “The highest risk was seen in subjects with type 2 diabetes.”
Researchers conducted a cross-sectional prospective study of 86 adults with a nonalcoholic fatty liver disease (NAFLD) diagnosis and available liver biopsy. Participants complete a clinical interview and examination, including disease history, self-reported questionnaires and blood tests. Three methods were used to measure alcohol consumption: a clinical interview, responses to the self-reported Alcohol Use Disorders Identification Test – Consumption (AUDIT-C) questionnaire, and phosphatidylethanol test results.
Participants were divided into a group with stage 0 to 2 fibrosis (n = 71) and a cohort with advanced fibrosis at stage 3 or 4 (n = 15). The advanced fibrosis group had higher weekly alcohol consumption than those with stage 0 to 2 fibrosis in both the AUDIT-C (47.5 g vs. 27.6 g) and clinical interview responses (56.3 g vs. 31.2 g).
Participants were further divided into four groups to determine whether type 2 diabetes was associated with advanced fibrosis. The first group had low alcohol consumption and no diabetes, the second group had low alcohol consumption and type 2 diabetes, the third group had moderate alcohol consumption without diabetes and the final group consisted of participants with moderate alcohol consumption and type 2 diabetes. Those with moderate alcohol consumption reported drinking more than 66 g per week on the AUDIT-C and more than 96 g per week in the clinical interview and had a phosphatidylethanol value of at least 50 ng/mL.
Compared with those who had alcohol consumption of up to 2.99 g per week, participants with type 2 diabetes and moderate alcohol consumption had increased risk for advanced fibrosis, independent of assessment. AUDIT-C results were associated with the highest risk for advanced fibrosis (adjusted OR = 9.7; 95% CI, 1.4-68.9), followed by clinical interview responses (aOR = 8.5; 95% CI, 1.05-69.6) and phosphatidylethanol values (aOR = 5.5; 95% CI, 1.4-22.1).
“There is evidence for beneficial effects of modest alcohol consumption on the risk of metabolic syndrome, insulin resistance and cardiovascular disease,” Kechagias said. “However, although moderate alcohol consumption may be protective in some aspects, it is most likely to be harmful for the liver if the aforementioned limit is exceeded in subjects with type 2 diabetes and fatty liver.”
Kechagias said adults with type 2 diabetes and NAFLD should be advised to reduce alcohol consumption to reduce their risk for advanced fibrosis.
“Many patients cannot tell the doctor the exact amount of alcohol they consume, either because they don’t remember or because, for some reason, they don’t want to,” Kechagias said. “We have shown that measurement of phosphatidylethanol in blood is a reliable tool for assessment of alcohol consumption. Patients with type 2 diabetes and fatty liver with phosphatidylethanol in blood of at least 50 ng/mL should also be advised to reduce alcohol consumption.”