Alcohol consumption and 5-year onset of chronic kidney disease: the AusDiab study

Background. Excessive alcohol consumption is a risk factor for hypertension and stroke; however, evidence for an association with chronic kidney disease is conflicting. Methods. A total of 6259 adults >= 25 years of age, without a history of alcohol dependence, participating in baseline (1999-2000) and follow-up (2004-2005) phases of an Australian population-representative study (AusDiab) were the subject of this analysis. Alcohol consumption status and volume/frequency were collected by standardized interviewer administered questionnaires and self-administered food frequency questionnaires. The outcomes were as follows: (i) 5-year decline in estimated glomerular filtration rate (eGFR) >= 10%, with baseline eGFR >= 60 and final eGFR < 60 mL/min/1.73 m(2), and (ii) 5-year doubling of albumin to creatinine ratio (ACR) with final ACR >= 2.5 (males)/>= 3.5 (females) mg/mmol, in the absence of albuminuria at baseline. Results. Self-identification as a moderate or heavy, versus light, drinker was associated with elevated risk of albuminuria in males and females < 65 years of age (OR, 95% CI: males 1.87, 0.99-3.52; females 2.38, 1.37-4.14). Odds of de novo eGFR < 60 mL/min/1.73 m(2) were 0.34 (95% CI 0.22-0.59) and 0.68 (95% CI 0.36-1.27) in males and females, respectively, who were moderate-heavy drinkers. Alcohol intake of >= 30 g/day was associated with an increased risk of albuminuria after adjustment for age, sex and baseline kidney function (OR = 1.59, 95% CI 1.07-2.36), but a reduced risk of eGFR < 60 mL/min/1.73 m(2) (OR = 0.59, 95% CI 0.37-0.95), compared with consumption of < 10 g/day. Conclusions. Moderate-heavy alcohol consumption may be an important modifiable risk factor for albuminuria in the general population. The natural history of alcohol-induced kidney damage and how this relates to markers of kidney function in the general population warrant further research.