Research shows sex differences in cardiac outcomes for dialysis patients

An interdisciplinary study involving eight University of Cincinnati College of Medicine experts has found significant sex differences in cardiovascular outcomes in patients with kidney failure. 

The study’s lead author will receive an international award for her work, which was published in the Journal of the American Heart Association. 

In one of the largest studies of its kind, researchers analyzed data from more than 500,000 patients undergoing dialysis in the United States and found that women have a higher risk of heart failure and stroke than men. However, women have a lower overall risk of cardiovascular death and death from all causes.

“To the best of our knowledge, it’s the first time these findings of a higher risk of cardiovascular events in women than men among those with kidney failure who are on dialysis have been reported in literature,” said Silvi Shah, MD, MS, FASN, FACP, an associate professor in UC’s Division of Nephrology and Hypertension in the Department of Internal Medicine and the study’s principal investigator. 

Researchers found women undergoing dialysis have a 14% higher risk of cardiovascular events, including a 16% higher risk of heart attack and a 31% higher risk of stroke than men. 

As for why, Shah and her collaborators have a number of theories.

One is the role of estrogen. It’s known that its protective properties decline in women undergoing dialysis, as they typically enter menopause years earlier than their healthy counterparts.

“Women also tend to receive less preventative kidney care, which can lead to the need for dialysis in the first place,” said Shah. “And women who suffer strokes tend to receive less care for them.”

Shah said women experiencing kidney failure also tend to start dialysis later than men. She added that when they do start dialysis, they tend to receive fewer hours of treatment than men.

Plus, women undergoing dialysis have higher rates of diabetes than men who are undergoing dialysis.  

As for why women in dialysis suffer cardiac events more often than men but survive, Shah said more research needs to be conducted. 

“We don’t know the real reason,” she said.

Her team believes it could be due to misdiagnoses or mismanagement of treatments.

“Women have to be treated differently when it comes to their heart health,” said Shah. “The study revealed significant sex differences in cardiovascular health. These disparities between the sexes and disparities in care point to the need for more personalized heart care for women,” said Shah.

She said the research revealed only some of what doctors need to keep in mind when monitoring a female patient’s cardiovascular health.

“Providers need to re-evaluate how they approach prevention and education on heart disease and stroke,” said Shah. “But this study underscores the importance of promoting overall heart health and healthy living, particularly for women who have kidney failure and are on dialysis.”

It also revealed that more research is needed on women undergoing dialysis — and it’s already in the works for Shah. 

She is planning a study to better understand the pathophysiology leading to more frequent cardiovascular events in women with kidney failure.

Shah’s study collaborators included Annette Christianson, MS, research associate in the Department of Biostatistics, Health Informatics and Data Sciences; Anthony Leonard, PhD, adjunct associate professor and biostatistician in the Department of Biostatistics, Health Informatics and Data Sciences; Karthikeyan Meganathan, PhD, adjunct assistant professor and data analyst in the Department of Biostatistics, Health Informatics and Data Sciences; Mark Mitsnefes, MD, professor in the Department of Pediatrics and pediatric nephrologist at Cincinnati Children’s Hospital Medical Center; Jack Rubinstein, MD, professor in the Division of Cardiovascular Health and Disease in the Department of Internal Medicine; Daniel Schauer, MD, MSc, adjunct associate professor in the Department of Internal Medicine; and Charuhas Thakar, MD, volunteer professor in the Division of Nephrology and Hypertension in the Department of Internal Medicine.

Shah’s research was supported by a career development award from the National Heart, Lung and Blood Institute of the National Institutes of Health.

AN AWARD FOR HER WORK

For her work, Shah is receiving the Dr. Nanette K. Wenger Research Goes Red Award for best scientific publication on cardiovascular disease and stroke in women published in an American Heart Association Journal. 

The award is given in recognition of the best research article published during the previous year in any of the association’s 14 peer-reviewed, scientific journals. Shah’s work was selected out of 137 submissions from 18 different countries. 
She will receive the award and present the winning research at the American Heart Association’s Scientific Sessions on Nov. 16 in Chicago.