It’s a frightening phrase that still rings true even after decades of medical progress and improvements in clinical intervention: in the United States, heart disease remains the number-one killer of both women and men. According to the Centers for Disease Control and Prevention, about 610,000 heart disease-related deaths occur in the US every year. That’s one out of every four deaths in the country. But what makes that statistic even more sobering is the fact that these deaths are not inevitable: a study recently published in the Annals of Internal Medicine reveals that preventable risk factors account for an astonishing half of the deaths due to heart disease.
The study was conducted by a team of researchers from the Rollins School of Public Health at Emory University and led by Dr. Shivani Patel of Rollins’ Hubert Department of Global Health. It aimed to generate new estimates of the percentage of heart disease deaths that could be prevented if certain risk factors were reduced or eliminated. To accomplish this, researchers worked with data collected by the Behavioral Risk Factor Surveillance System (BRFSS), the country’s leading system of health-related telephone surveys that gathers information from each state on people’s chronic health conditions, health-related risk behaviors, and use of preventative services. Specifically, the research team examined data collected in 2009 and 2010 from adults between 45 and 79 years old, focusing their analysis on the five leading modifiable risk factors for heart disease: smoking, obesity, diabetes, hypertension, and elevated cholesterol. To estimate the relative chance of death from heart disease associated with these risk factors, the team used additional data from the National Health and Nutrition Examination Survey, a program of studies which combines interviews and physical examinations to assess the health and nutritional status of US adults and children.
The findings were striking. In the best-case scenario, with the complete elimination of the top five modifiable risk factors, 54% of male heart disease deaths and 49.6% of female heart disease deaths in 2009-10 could have been prevented. In other words, about half of all heart disease deaths in the US during that period were theoretically preventable.
Naturally, the complete elimination of obesity, diabetes, hypertension, smoking, and high cholesterol is not a realistic scenario. To create a more feasible target scenario and to ground their findings more firmly in a realistic context, the Emory researchers also examined what would happen if those same top five modifiable risk factors were not totally eliminated, but rather reduced to the levels in the five states with the best performance record for each risk factor within gender and age groups.
These results were less striking, but still significant. For example, for men aged 45 to 54, 7% of heart disease deaths could be prevented if smoking rates in all states matched the levels of the best-performing states for smoking. Similarly, for women aged 55 to 64, a decrease in hypertension rates to those of the best-performing states in that category would prevent 8% of heart disease deaths.
Although these smaller percentages would still make a difference against the 610,000 annual heart disease deaths in the US, they show how far the nation has to go in terms of preventing and reducing risk factors for heart disease. Some states perform better than others in terms of risk factors; Colorado, Vermont, and Utah are consistently among the best-performing states across gender and age groups, while Southern states like Kentucky, West Virginia, and Mississippi typically have the highest risk levels. However, the fact remains that even the best states could be performing far better. Given the difference between the percentage of preventable deaths associated with complete risk factor elimination, versus the percentage associated with reducing risk factors to the levels in the best-performing states, it is clear that all states would benefit from pursuing risk factor reduction more aggressively through policies and programs.
For the general public, the takeaway message from the study is that even a few basic lifestyle changes could greatly reduce the risk of death from heart disease. This is especially important to consider given the fact that risk factors tend to cluster, meaning that it is common for people with one risk factor to be affected by others as well, thus further increasing their overall risk. Of course, certain factors that contribute to the development of heart disease are beyond individual control, such as age, genes, or environmental air quality, but addressing those risk factors that can be controlled has a major impact, as the study shows. Some of the most important actions people can take to reduce their preventable risk factors include exercising regularly, eating a balanced diet, and quitting smoking.