Researchers in Alberta, Canada, have found that untreated renal failure is significantly more common in older than younger individuals, according to a new report published in the Journal of the American Medical Association (2012;307:2507-2015).
In a study that included more than 1.8 million adults, the adjusted rates of untreated kidney failure cases among individuals in the lowest stratum of estimated glomerular filtration rate (eGFR 15-29 mL/min/1.73 m2) were 3.53 per 1,000 person-years for those aged 18-44 years versus 19.95, 13.25, and 8.54 per 1,000 person-years for those aged 85 years and older, 74-84 years, and 65-74 years, respectively.
Untreated kidney failure among patients aged 75 years or older with a baseline eGFR of 15-29 was about 2- to 10-fold more common than kidney failure treated by dialysis, according to the report.
The investigators defined untreated kidney failure as progression to an eGFR below 15 without renal replacement therapy.
The researchers, led by Brenda R. Hemmelgarn, MD, PhD, of Foothills Medical Centre in Calgary, observed that their results “suggest that the incidence of advanced kidney disease in the elderly may be substantially underestimated by rates of treated kidney failure alone and that untreated kidney failure may be more common than initiation of renal replacement at older ages.”
Dr. Hemmelgarn noted that the study findings also highlight that “CKD does progress among older adults, and suggests a need to prioritize the assessment and recognition of CKD progression among older adults so that shared decision making regarding strategies for management, including supportive care, can be made.”
In an accompanying editorial (pp. 2545-2546), Manjula Kurella Tamura, MD, MPH, and Wolfgang C. Winkelmayer, MD, MPH, ScD, both of the Stanford University School of Medicine in Palo Alto, Calif., noted that the magnitude of untreated kidney failure among older adults does not necessarily imply inappropriate withholding of treatment. “While the study describes the rates of untreated kidney failure for older adults,” they wrote, “it does not provide information on the reasons these patients did not undergo dialysis or kidney transplantation or about alternative treatments they might have received. It is possible that older patients may have decided, after a shared decision-making process with their medical team and family, to forego dialysis and to opt for supportive care.”
Drs. Tamura and Winkelmayer concluded that the work by Dr. Hemmelgarn and colleagues “highlights a potentially sizeable unmeasured burden of untreated kidney failure among older adults. It is of paramount importance to refine the current understanding of what constitutes appropriate treatment for kidney failure, which factors influence the decision-making process, and which methods are optimal for aligning treatment plans with patient goals and prognosis.”