Risk Factors for Cardiovascular Disease

Manesh R. Patel, MD: Cardiovascular disease and diabetes are so intertwined. So it’s important to first think about the prevalence of diabetes and then think about its effect on cardiovascular disease.

Diabetes is a disease affected by nutrition and obesity. In the United States, the prevalence of diabetes has increased significantly over the last decade. In 2018, the American Heart Association said that about 30% of the American population is obese. This is a significant finding. And then from 2013 to 2016, an estimated 26 million American adults, or 9.8% of the population, has been diagnosed with diabetes. That’s a significant number of patients with diabetes. These people have an increased risk for cardiovascular disease, which includes myocardial infarction, stroke, limb events, and amputations. It’s estimated that morbidity and mortality of diabetes will increase significantly over the next decade and account for at least a quarter of the morbidity and mortality from cardiovascular disease.

The role of our population in general and ethnic distribution and even health equity are critical, when we think about diabetes and cardiovascular disease. Unfortunately, it’s communities of color, people from different socioeconomic backgrounds, social determinants of health, and certainly diverse populations of patients who have the highest risk of diabetes. We know from our African American and Hispanic colleagues that the rate of diabetes is at least 1 to 1.5 times higher in parts of the United States. It’s expected that up to 12% to 15%—again, from the American Heart Association—of Hispanic people, men and women, in the next decade will go on to have diabetes at a rate higher than some of our colleagues in other parts of the country. We know that there are some populations being affected more by diabetes. We also know that additionally, almost 91 million Americans, or 37% of adults, may have prediabetes, which is obesity and risk factors for diabetes. That is overrepresented in our Hispanic patients and our African American patients in the United States.

It’s really an important message: the link between metabolic syndrome—prediabetes or obesity—and then diabetes and cardiovascular-related morbidity and mortality. To make sure everybody is on the same page, let’s remember that metabolic syndrome is when patients have an increased waist circumference. And certain groups of populations have certain cut points; elevated triglycerides, remembering that a nonfasting triglyceride greater than 150 mg/dL is felt to be elevated; elevated blood pressure, generally above 135/80 mmHG; elevated glucose, maybe not quite to the diabetic level; and a low calculated or measured HDL [high-density lipoprotein], which in men is less than 40 mg/dL and in women is 50 mg/dL. These are all factors.

Any 3 of those factors that I’ve just described identifies people with metabolic syndrome. Metabolic syndrome is a syndrome in which you have a high amount of tissue that’s skeletal muscle, often fat, central obesity as you’ve highlighted and just discussed. But also triglycerides and an inability to manage and deal with the components of it, of a diet that has carbohydrates or a diet that has fats. What metabolic syndrome often leads to is nonalcoholic steatosis hepatic disease, or NASH. It leads to prediabetes and eventually to diabetes. These conditions have been associated with the higher risk of cardiovascular disease and a significantly higher risk of cardiovascular mortality. 

It’s important to recognize that according to the American Heart Association, in 2018 and 2019 an estimated 1.6 million deaths were attributed to diabetes globally. That’s a mortality rate estimated yearly of about 19½ people per 100,000. The scourge in the world and in the United States is obesity leading to metabolic syndrome, which then leads to morbidity and mortality, usually through cardiovascular channels.

Marc P. Bonaca, MD, MPH: When we think of cardiovascular disease there are several risk factors, particularly for atherosclerotic vascular disease. The cholesterol plaque that diseases the arteries in the coronary bed, the cerebral vascular bed, and the lower extremities is what we call peripheral artery disease. Some of the most potent risk factors for that are diabetes mellitus, smoking or even a prior history of smoking, hypertension, hypercholesterolemia, and then lifestyle-related things such as inadequate activity, obesity, and other things like sleep apnea. But diabetes, hypertension, and hyperlipidemia are some of the key risk factors that we think about for the development of atherosclerotic vascular disease.

Transcript Edited for Clarity