Written by Sabir Khan, fourth-year medical student, University College Dublin, Ireland, and participant in the 2021 Institute for Public Health Summer Research Program
One of the great things about being part of the participant in the 2021 IPH Summer Research Program – Public and Global Health Track is that we attend seminars on topics delivered by experts in their field. On July 1, I had the wonderful opportunity to attend a seminar delivered by Victor Davila-Roman, MD, director of the Global Health Center, in which he discussed the global burden of cardiovascular disease.
Dr. Davila began by explaining the incidence and mortality rates of cardiovascular diseases (CVDs), which are the leading cause of death in the United States. What was surprising is that even during the COVID-19 pandemic, during which millions of people died, the number one cause of death remained unchanged – CVDs. Covid-19 affected people with an underlying CVD more severely. Furthermore, Dr. Davila emphasized that CVDs are not just a health burden on the affected population, but also an economic burden on society as a whole. The global cost of CVD projected for the year 2030 is $1,044 billion per year!
One of the main risk factors for the development of CVD is hypertension. Hypertension is defined as a systolic blood pressure above 140mmHg and a diastolic blood pressure above 90mmHg. A very interesting aspect of hypertension is the prevalence of this condition in low-middle income countries (LMIC) compared to high-income countries. In 2010, 1.39 billion people were affected by hypertension, of which 1.04 billion (75%) were in LMIC. Furthermore, ethnic minority groups such as American Indians, African Americans, and Hispanics have a much higher prevalence and mortality of CVDs compared to Caucasians.
The good news is hypertension is a modifiable risk factor. For every 10mmHg decrease in systolic blood pressure, there is a significant reduction on the risk for many cardiovascular events (such as Myocardial Infarction/Stroke etc.). Individuals can reduce hypertension with medication, diet and exercise. An alarming statistic was that 50% of people with hypertension are not aware of it, and 50% of those who are, don’t have it under control.
According to Dr. Davila, a common trend seen throughout most CVDs is an increase in incidence rate with age. By the age of 75, 80% of the population has high blood pressure. Stroke, a loss of bloody supply to the brain, also increases with age and with blood pressure. Finally, the incidence of Ischemic heart disease/Coronary heart disease (a loss of blood supply to the heart muscle,) demonstrates the same trend: an increase with age and blood pressure. Dr. Davila explained that the development of Ischemic heart disease begins as a simple fatty streak, which is present around the late teens. Over time, the fatty streak progresses into a fibrous plaque, and eventually an atherosclerotic plaque which can rupture resulting in a thrombus. This thrombus can block the artery supplying blood to the heart muscle, resulting in ischemic damage to the heart muscle. This really shows the significance of regular check-ups on a developing condition that can be caught and corrected a lot earlier before it’s too late.
The Centers for Disease Control and Prevention recommends getting a cholesterol screening every four to six years after the age of 21. Those with a family history of CVDs should get their cholesterol checked more frequently.