A panel of experts provide an overview of the pathophysiology, patient population, and prevalence of cardiorenal metabolic syndrome.
Neil Minkoff, MD: Hello, and welcome to this AJMC Peer Exchange® program, titled “Population Health Implications of Cardiorenal Metabolic Syndrome.” I’m Dr Neil Minkoff, the chief medical officer of Coeus Healthcare and Consulting. Joining me today in this virtual discussion are my colleagues: Dr Desai, associate professor of medicine and associate chief of cardiovascular medicine at Yale University School of Medicine, as well as an investigator at the Center for Outcomes Research and Evaluation; Dr Jeff Turner, associate professor of nephrology at the Yale University School of Medicine; and Dr Ganda, senior physician and medical director of the Lipid Clinic at the Joslin Diabetes Center, as well as associate professor of medicine at Harvard Medical School.
Today, our panel of experts will explore opportunities to improve population health outcomes in cardiorenal metabolic syndrome, including clinical and paired considerations of emerging diabetes treatments. Let’s begin. I’d like to start by trying to understand the interplay between metabolic syndrome, which I think many people are familiar with—cardiovascular disease, and renal dysfunction, which is now becoming known as cardiorenal metabolic syndrome. Dr Turner, could you lead a discussion in trying to let our audience understand an overview of cardiorenal metabolic syndrome and some of the pathophysiology?
Jeffrey Turner, MD: Cardiorenal metabolic syndrome, or cardiorenal syndrome, is an umbrella term that encompasses a lot of different types of pathophysiologies. It highlights the important relationship between the kidneys and the heart as the 2 main organs that are involved in this process. Injury can start in 1 organ and transfer to the other in either direction. Our understanding of this disease process has developed. In its infancy, it used to be understood that the heart was a pump; it didn’t pump well, and therefore, the kidneys lacked good blood supply. That was the mechanism of injury, but our understanding of this has evolved in recent years through different studies. It’s much more complicated than just hemodynamics. It also involves neurohormonal and inflammatory systems. Thus, more contemporary research and ideas surrounding the pathophysiology have started to encompass metabolic syndrome, including diabetes and lipids. They’re all at interplay, causing this disease process to take place.
Neil Minkoff, MD: There’s a significant link between metabolic syndrome, renal dysfunction, and diabetes, as well as the related cardiovascular morbidity and mortality. Dr Ganda, at the Joslin [Diabetes Center], you’re seeing a lot of diabetes. Could you weigh in on how those different conditions link together and impact morbidity and mortality?
Om P. Ganda, MD: As Dr Turner was indicating, this is a common entity. It’s a constellation of various parameters, which include glycemic abnormalities, obesity, high blood pressure, and dyslipidemia. Obesity is one of the common features, although it doesn’t have to be there. One of the common links is insulin resistance. One can recall that early studies showed that with insulin resistance we can identify the type of dyslipidemia that occurs in diabetes, as well as hyperglycemia in the presence of beta cell deficiency. Obesity is a common link because the US population, like everywhere else in the world, is more obese than ever. There’s evidence that an obesity and kidney disease link has been underappreciated, while we already know the link between obesity, diabetes, and cardiovascular disease. Some of the new data is beginning to show that obesity can lead to renal dysfunction and, consequently, cardiovascular disease. I’m sure we’ll be discussing some of these things in today’s conference.
Neil Minkoff, MD: How widespread is this? Dr Desai, you’ve been looking at this for some time. Could you help us define incidence or prevalence, or where we need to be looking for this within the patient population?
Nihar R. Desai, MD, MPH: As our understanding of this clinical syndrome has continued to evolve and advance, I think the prevalence of these sort of conditions also continues to grow. We know that the various clinical conditions that we’re talking about here—whether it’s heart failure or diabetes or kidney disease—are rising in incidence and prevalence. The overlap of these clinical conditions also continues to grow exponentially. The numbers that I’ve seen are staggering; among patients with heart failure, a quarter of them may have diabetes. If you flip it and look at it the other way, approximately 10% to 20% of patients with diabetes have heart failure. Similarly, up to a quarter of patients that are hospitalized for acute heart failure will develop acute kidney injury, or potentially cardiorenal syndrome, as Dr Turner was alluding to. It’s the exception to the rule that a patient with heart failure has normal renal function. Most of our patients with heart failure will have some degree of renal dysfunction. Again, there are multiple mechanisms at play there. As you put these things together, it highlights the challenge of various clinical conditions all coming together in the patients that we are managing with cardiovascular disease, renal dysfunction, and then with metabolic disease and diabetes.
Neil Minkoff, MD: It’s been commonplace for a long time to be thinking about this with more advanced age. Is there a particular gender bias, or is it seen in different races or ethnicities? What are the other comorbidities that we should be looking for?
Nihar R. Desai, MD, MPH: Older age is one of the important risk factors, as well as the presence of diabetes, underlying kidney dysfunction, and hypertension. There’s a slight male predominance in the development of cardiorenal syndrome, but again, constellation of features—for that patient who’s hospitalized, maybe with acute heart failure, and then develops a rise in their serum creatinine. Some of the contributing factors to that might be the presence of diabetes, hypertension, advanced age, and male gender. I think those are features that make it more likely for the patient to develop a cardiorenal-type picture if they are hospitalized for heart failure.
Transcript edited for clarity.