The predictive value of albuminuria for renal and nonrenal natural deaths over 14 years follow-up in a remote aboriginal community

Background: Australian aboriginal people living in remote regions have extraordinary higher rates of mortality compared with other Australian ethnicities. Albuminuria marks the underlying renal disease. This study assessed the predictive value of albuminuria for nonrenal and renal deaths in a remote Australian aboriginal community over a follow-up period of >14 years.

Methods: From 1992 to 1997, 85% of community members participated in a health screen, which included measurement of urine albumin/creatinine (ACR) levels. Deaths and dialysis initiations were recorded until 30 November 2010. The rates of natural nonrenal and renal deaths were assessed over a mean of 14 years in the 956 participants aged 18 years and over at baseline, and mortality associated with baseline levels of albuminuria (ACR ≥ 2.7 mg/mmol) was estimated.

Results: There were 203 natural deaths; 70 were renal deaths and 133 were nonrenal deaths, including 60 cardiovascular disease (CVD) deaths. Higher baseline ACR predicted all categories of natural death, with no apparent lower threshold for effect. Baseline ACR ≥ 2.7 mg/mmol predicted a 3.3-fold increase in all natural deaths, a 2-fold increase in nonrenal deaths and a 1.7-fold increase in CVD deaths, after adjustment for other factors. Eighty-nine percent (62 out of 70) of renal deaths occurred in those with ACR ≥ 34 at baseline, with a 24-fold increase in risk. Albuminuria (ACR ≥ 2.7 mg/mmol) contributed to 66% of risk for all natural deaths over the interval.

Conclusions: Albuminuria was still a remarkable predictor for all-cause natural death over an average of 14 years follow-up interval in this aboriginal community.