According to promising new research, analyzing protein levels in the urine may be a better predictor of kidney function than the old method, which involved monitoring creatinine levels. As the researchers say in a NIH−Medline (Reuters) release, it’s likely that this new method will be embraced as part of the new guidelines for assessing kidney function.

In the study, the team led by Brenda R. Hemmelgarn looked at both the estimated glomerular filtration rate (eGFR) and proteinuria (protein level in the urine) in close to one million participants over a period of five years.

As proteinuria levels increased, the researchers saw that patients were more likely to suffer from kidney failure, heart attack, and death.

They found that individuals who had high protein levels but low eGFR were at much higher risk of kidney failure and death than were individuals who had high eGFR and normal proteinuria. As proteinuria levels increased, the researchers saw that patients were more likely to suffer from kidney failure, heart attack, and death. Additionally, individuals with higher proteinuria but eGFR levels closer to the normal range suffered from more negative “clinical outcomes,” than those with lower GFR and no proteinuria.

Hemmelgarn says, in the NIH−Medline release, that she and her team “found that including another marker of kidney health — the level of protein in the urine — helps to better predict risk than” looking solely at serum creatinine. She adds that she feels that “it's very likely to get adopted in the new guidelines” that clinicians use to predict who’s at risk of kidney problems, which will be available in the second half of 2011.

Kidney disease can have serious clinical implications, so any tool that helps clinicians accurately predict who is at risk for developing it comes as a tremendous boon to the medical community.

The study was conducted by researchers at the University of Calgary in Alberta, Canada and published in the February issue of the Journal of the American Medical Association.