Moderate Alcohol Use and Insulin Action in Chronic Hepatitis C Infection

Chronic hepatitis C (HCV) is associated with metabolic abnormalities including insulin resistance (IR) and diabetes. While moderate alcohol consumption is known to have beneficial metabolic effects in the general population, such potential effects in HCV are unknown. We aimed to assess the association between graded alcohol intake and IR, insulin secretion, and metabolic syndrome in HCV.

Ninety-five non-diabetic HCV-infected patients underwent detailed metabolic testing. IR was directly measured via steady-state plasma glucose (SSPG) during a 240-min insulin suppression test. Total insulin secretion and insulinogenic index were determined by 75-g oral glucose tolerance test. Genotyping of CYP2E1 was performed to detect genetic polymorphisms influencing alcohol metabolism.

In this cohort, 61 % were abstinent from alcohol for the past 12 months, while 22 % were moderate, and 17 % heavy drinkers. Obesity and nonwhite ethnicity were the strongest predictors of IR. Moderate alcohol intake (vs none) was significantly associated with lower SSPG only among those with normal BMI (coef -72.9, 95 % CI -128.1 to -17.6, p = 0.01). Alcohol use was not associated with insulin secretion parameters when controlling for IR and other factors. Heavy alcohol intake (OR 3.2, 95 % CI 0.86-12.3) and nonwhite ethnicity (OR 7.1, 95 % CI 1.5-33.3) were associated with metabolic syndrome. Among nonwhites, the odds of metabolic syndrome were fivefold higher for heavy drinkers.

Moderate alcohol intake is associated with improved insulin sensitivity in HCV, although this benefit was limited to normal-weight individuals. The potential benefit of moderate alcohol on IR and its metabolic consequences in HCV warrants further longitudinal investigation.