Lifetime CKD Risk High in the U.S.
Moderate to severe chronic kidney disease (CKD) is predicted to develop in more than half of the individuals born in the United States today during their lifetime, according to findings of a recent study published in the American Journal of Kidney Diseases (2013;62:253-260).
The study, by Morgan E. Grams, MD, MHS, and colleagues at Johns Hopkins University in Baltimore, also showed that women experienced a greater risk of CKD but a lower risk of end-stage renal disease (ESRD) than men.
The estimated onset of CKD was earlier in blacks than whites, according to the researchers. By age 60, 10.3% of black men and 10.4% of black women were projected to have CKD stage 3a or higher compared with 6.9% and 7.8% of white men and white women, respectively.
From birth, CKD stage 3a or greater—defined as an estimated glomerular filtration rate below 60 mL/min/1.73 m2—was predicted to develop in an estimated 59% of the overall U.S. population, Dr. Grams' group reported. The estimated overall lifetime risk of ESRD from birth was 3.6%. The estimated lifetime risk of CKD stage 3a or higher from birth for white men, white women, black men, and black women was 53.6%, 64.9%, 51.8%, and 63.6%, respectively. The predicted lifetime risk of ESRD for white men, white women, black men, and black women was 3.3%, 2.2%, 8.5%, and 7.8%, respectively.
“Thus, within each race, women had higher lifetime risks of CKD, whereas men had higher risks of ESRD,” the authors wrote.
The study showed that CKD risk increased with age, with approximately half the CKD stage 3a or higher cases developing after age 70.
Commenting on the new study, Beth Piraino, MD, President of the National Kidney Foundation, observed that the new findings “show clearly that Americans are more likely than not to develop kidney disease.”
“Importantly, if caught early, the progression of kidney disease can be slowed with lifestyle changes and medications,” Dr. Piraino said. “This underscores the importance of annual screenings, especially the at-risk population, to potentially prevent kidney disease and ensure every patient with kidney disease receives optimal care.”
Dr. Grams's group analyzed annual probabilities of death for the U.S. population by age, gender, and race using the National Vital Statistics Report. They estimated CKD prevalence using data from the National Health and Nutrition Examination Survey (NHANES), a population-level survey of community-dwelling U.S. civilians conducted by the National Center for Health Statistics. The study population was limited to individuals aged 20 years and older who had serum creatinine, urine albumin, and urine creatinine values available.
In an editorial accompanying the new report, Raymond K. Hsu, MD, and Chi-yuan Hsu, MD, of the University of California San Francisco, observed that the data used by Dr. Grams and colleagues “are a decade old or older by now.” More recent NHANES data reveal no change in CKD prevalence during the past 10 years, Drs. Hsu and Hsu noted. The prevalence of CKD stages 3-4 was 8.1% in 2001-2002, 7.7% in 2003-2004, 8.1% in 2005-2006, 8.0% in 2007-2998, and 7.8% in 2009-2010. Additionally, they stated that the prevalence of early stage CKD has not increased in the last decade.
“It is easy to assume that as a result of CKD risk factors such as older age and diabetes mellitus becoming more common, CKD must have become more prevalent,” according to the editorial. “However, this is not necessarily true because medical treatment also has advanced considerably in the past several decades.”
For example, large strides have been made in glycemic control, which has been shown to reduce the risk of incident CKD, according to the editorial.
Drs. Hsu and Hsu also pointed out that the U.S. Renal Data System “consistently has reported that the incidence of ESRD in the United States has reached a plateau in many groups during the past decade, in sharp contrast to the rapid increase seen in the 1980s and 1990s.”