Alcohol as a risk factor for liver cirrhosis: a systematic review and meta-analysis

INTRODUCTION AND AIMS

Alcohol is an established risk factor for liver cirrhosis. It remains unclear, however, whether this relationship follows a continuous dose-response pattern or has a threshold. Also, the influences of sex and end-point (i.e. mortality vs. morbidity) on the association are not known. To address these questions and to provide a quantitative assessment of the association between alcohol intake and risk of liver cirrhosis, we conducted a systematic review and meta-analysis of cohort and case-control studies.

DESIGN AND METHODS

Studies were identified by a literature search of Ovid MEDLINE, EMBASE, Web of Science, CINAHL, PsychINFO, ETOH and Google Scholar from January 1980 to January 2008 and by searching the references of retrieved articles. Studies were included if quantifiable information on risk and related confidence intervals with respect to at least three different levels of average alcohol intake were reported. Both categorical and continuous meta-analytic techniques were used to model the dose-response relationship.

RESULTS

Seventeen studies met the inclusion criteria. We found some indications for threshold effects. Alcohol consumption had a significantly larger impact on mortality of liver cirrhosis compared with morbidity. Also, the same amount of average consumption was related to a higher risk of liver cirrhosis in women than in men.

DISCUSSION AND CONCLUSIONS

Overall, end-point was an important source of heterogeneity among study results. This result has important implications not only for studies in which the burden of disease attributable to alcohol consumption is estimated, but also for prevention.

Alcohol use and mortality in older men and women

AIMS

To compare the effect of alcohol intake on 10-year mortality for men and women over the age of 65 years.

DESIGN, SETTING AND PARTICIPANTS

Two prospective cohorts of community-dwelling men aged 65-79 years at baseline in 1996 (n = 11 727) and women aged 70-75 years in 1996 (n = 12 432).

MEASUREMENTS

Alcohol was assessed according to frequency of use (number of days alcohol was consumed per week) and quantity consumed per day. Cox proportional hazards models were compared for men and women for all-cause and cause-specific mortality.

FINDINGS

Compared with older adults who did not consume alcohol every week, the risk of all-cause mortality was reduced in men reporting up to four standard drinks per day and in women who consumed one or two drinks per day. One or two alcohol-free days per week reduced this risk further in men, but not in women. Similar results were observed for deaths due to cardiovascular disease.

CONCLUSIONS

In people over the age of 65 years, alcohol intake of four standard drinks per day for men and two standard drinks per day for women was associated with lower mortality risk. For men, the risk was reduced further if accompanied with 1 or 2 alcohol-free days per week.