Elevated albuminuria, micro- or macro-, may be a more useful marker of cardiac disease than renal disease. We are used to thinking of albuminuria as a marker of renal function, and it is true that it is a reasonable predictor of future renal function. However, studies over the last decade have shown that eGFR (estimated GFR) is a more practically useful indicator of present and future renal function than albuminuria. Although treatment with angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) lower the levels of micro- or macro-albuminuria, they are effective in decreasing the progression to renal failure only when the eGFR is low, regardless of the levels of albuminuria. This report from Japan adds to number of studies showing that albuminuria has a strong association with increased cardiovascular risk. This is true in people with and without diabetes, and the associations are still signigicant when albuminuria is within the ‘normal’ range. I’ve wondered if this may be due to the fact that elevated albuminuria reflects atherosclerotic changes over a period of time, almost serving as an integrative indicator of past blood pressure, dyslipidemia and inflammation. I should note that there is little experimental data supporting this direct connection, but that it does provide a useful approach to using and interpreting albuminuria levels.
See abstract here.