People with failing kidneys are at increased risk of developing a life-threatening abnormal heart rhythm, a new report suggests.
Chronic kidney disease can as much as double a patient’s risk of atrial fibrillation, a quivering or irregular heartbeat that can lead to stroke or heart failure, said lead researcher Dr. Nisha Bansal. She is an associate professor of nephrology at the University of Washington’s Kidney Research Institute, in Seattle.
The risk of atrial fibrillation increases as kidney function declines, Bansal said. “We saw the worse your kidney function, the greater your risk of developing atrial fibrillation. Even mild changes in kidney function were strongly linked to atrial fibrillation,” Bansal noted.
The study included data gathered from three separate research projects focused on heart health in the United States. The three projects created a combined pool of almost 17,000 patients with follow-up periods averaging between 8.5 and 12.5 years. None of the participants had atrial fibrillation when first recruited.
People with worse kidney function at the start of the study were more likely to have atrial fibrillation by the end, the researchers found. Those who did worse on the blood test [GFR] were twice as likely to develop an abnormal heart rhythm, while those who did worse on the urine test [urine protein] were 76% more likely.
“We found that kidney function was independent of all other risk factors,” Bansal said.
A poorly functioning kidney can alter blood levels of a number of nutrients needed to maintain proper heart function, such as potassium, vitamin D, calcium and phosphorus, Bansal said.
The kidneys also are responsible for maintaining a steady volume of blood in your body, removing excess fluid by way of urination. “If your kidney function is impaired, your blood volume increases,” Bansal said. “That increased stress on your heart causes it to stretch and can also trigger this abnormal heart rhythm.”
Dr. Kevin Chan, a nephrologist with Massachusetts General Hospital in Boston, noted that it’s also possible toxins that haven’t been filtered from the blood – thanks to a bad kidney – might have some as-yet-unknown effect on heart function. Based on this report, doctors treating patients with kidney disease should keep an eye out for potential heart problems, said Chan, who was not involved with the new study. “Physicians should be cognizant of this relationship so they are attuned to recognizing atrial fibrillation when they see their chronic kidney disease patients,” Chad said.
The report was published online Aug. 10 in the Clinical Journal of the American Society of Nephrology.
Please reread the blog I posted on April 24, 2017 “Kidney Disease a Big Contributor to Heart-Related Deaths”
The GFR (glomerular filtration rate) is largely ignored by the medical community until it shows advanced kidney damage. This is the second study linking this common medical test to heart health.
The GFR is part of the CMP (comprehensive metabolic profile), a panel of routine laboratory tests that includes the fast glucose, liver enzymes, electrolytes and other measures of kidney function. Some labs still list the test as “greater than 60” (>60) rather than report the actual test level. This is a dangerous practice as levels between 60 and 90 indicate impaired kidney function. Levels below 60 indicate kidney damage.
The Bottom Line:
Physicians need to monitor any GFR levels below 90 for possible heart issues, including atrial fibrillation. Whether your doctor does or not, you should review your most recent lab tests. Make sure your GFR is at least 90. If it is less than 90 bring it to your doctor’s attention. If they ignore the test, seek a second opinion.
Source: August 10, 2017 National Institutes of Health