Thirty million American adults have chronic kidney disease -- but many don't know it.
That rate -- one in seven -- is higher than previously estimated, according to an analysis of data from the U.S. Centers for Disease Control and Prevention.
The findings, based on 2011-2014 statistics, should "serve as a warning bell that a major public health challenge is right in front of our eyes and more must be done to address it," Kevin Longino, CEO of the National Kidney Foundation, said in a news release from the group.
Chronic kidney disease occurs when the kidneys are damaged or can't filter blood as well as healthy kidneys. As a result, the body retains excess fluid and waste from the blood, which can cause other health problems.