The 40th anniversary of the National Institute on Alcoholism and Alcohol Abuse: the impact on liver disease

Moderate Alcohol Use and Insulin Action in Chronic Hepatitis C Infection

BACKGROUND AND AIM

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Alcohol and HCV: implications for liver cancer

Liver cancers are one of the deadliest known malignancies which are increasingly becoming a major public health problem in both developed and developing countries. Overwhelming evidence suggests a strong role of infection with hepatitis B and C virus (HBV and HCV), alcohol abuse, as well as metabolic diseases such as obesity and diabetes either individually or synergistically to cause or exacerbate the development of liver cancers. Although numerous etiologic mechanisms for liver cancer development have been advanced and well characterized, the lack of definite curative treatments means that gaps in knowledge still exist in identifying key molecular mechanisms and pathways in the pathophysiology of liver cancers. Given the limited success with current therapies and preventive strategies against liver cancer, there is an urgent need to identify new therapeutic options for patients. Targeting HCV and or alcohol-induced signal transduction, or virus-host protein interactions may offer novel therapies for liver cancer. This review summarizes current knowledge on the mechanistic development of liver cancer associated with HCV infection and alcohol abuse as well as highlights potential novel therapeutic strategies.