How Kidney Function Affects the Heart

Medically Reviewed

People with long-standing kidney disease are known to be at increased risk of heart disease, but doctors haven’t been sure whether the risk is from the kidney disease itself or from factors such as high blood pressure that tend to occur at the same time.

Now, research published in a February 2016 issue of Hypertension supports the idea that even small reductions in kidney function may increase the risk of cardiovascular disease.

For the study, researchers collected data on 68 people who had donated a kidney and 56 control patients who had not been kidney donors. As expected, kidney donation led to reductions in kidney function one year after the surgery. There was no change in blood pressure.

Compared with the controls, however, kidney donors experienced more enlargement of the heart’s left ventricle—a sign of elevated heart disease risk. Blood tests also revealed an increase in signs of heart damage.

The study authors noted that kidney donors likely remain at lower than average risk of heart disease even if there is a small increase in risk because only the healthiest people are allowed to donate organs.

Based on these results, however, people with impaired kidney function should discuss with their doctor ways to reduce their risk of heart disease.