Online risk calculator predicts chance of kidney failure for CKD patients
Key Takeaways
A risk calculator can accurately predict whether a patient with stage 3 to 5 chronic kidney disease (CKD) will develop kidney failure in the next 2 to 5 years, according to a study published January 12, 2016 in JAMA.
“This tool allows doctors to sit down with their patients and explain how likely it is that their kidneys will fail in the near future,” said Josef Coresh, MD, PhD, the George W. Comstock Professor of Epidemiology at the Johns Hopkins Bloomberg School of Public Health in Baltimore, MD, and head of the Chronic Kidney Disease Prognosis Consortium, which conducted the study.
“While the tool can aid in management of a patient’s disease and prepare them for the worst, many more patients will find the results reassuring,” Dr. Coresh added. “You can reassure a lot of worried people with the fact that their risk is actually very low. The vast majority of patients will not need dialysis.”
Now available online at www.kidneyfailurerisk.com, the risk calculator uses 4 variables—age, sex, glomerular filtration rate, and urine albumin/creatinine ratio—to provide the percentage risk of kidney failure at 2 years and at 5 years, as well as the patient’s estimated stage of CKD.
In the JAMA study, Dr. Coresh and colleagues sought to validate the risk equations, which were originally developed in a Canadian population, using data from more than 721,000 patients with stages 3 to 5 CKD, with a wide range of variation in age, sex, and race, in 30 countries.
The researchers concluded that a 4-variable risk calculator accurately predicted the risk of kidney failure in 2 and 5 years, and an 8-variable calculator (which also included variables of blood calcium, phosphate, bicarbonate, and albumin levels) did moderately better.
The researchers found that the results in the United States were similar to those in the original Canadian study. But for some countries outside North America, the original Canadian equations overestimated risk in some cohorts. When the researchers added a calibration factor that lowered the baseline risk, it improved the accuracy of the equation for most cohorts.
“We’ve known which were the important tests to consider in determining the risk of kidney failure, but we didn’t know exactly how to put them together and we didn’t have a high level of confidence that this tool could be used widely,” Dr. Coresh said. “Now we do.”
The online risk calculator can be a helpful tool in managing kidney disease among those at risk, according to the National Kidney Foundation, which supported its development. Results of the calculator could be a “wake-up call” to promote better compliance with medication, diet, and lifestyle changes for some patients. It also can give patients and physicians time to plan for potential dialysis and/or transplant.
“Dialysis and transplantation are expensive and complicated and take planning,” said study co-author Morgan E. Grams, MD, PhD, a nephrologist and Assistant Professor of Epidemiology at the Bloomberg School. “Knowing ahead of time allows people to consider their options.”