February 2 is National Wear Red Day, kicking off American Heart Month. We join our colleagues at the National Heart, Lung, and Blood Institute (NHLBI) in The Heart Truth program to increase awareness that heart disease is the leading cause of death among women and to increase awareness of the risk factors for heart disease.
A few of the risk factors for heart disease are out of our control – getting older, having a family history of early heart disease or a history of preeclampsia during pregnancy – but most of the risk factors for heart disease are modifiable behaviors.
Quitting smoking is the single most important step for preventing coronary artery disease. The Clinical Guidelines for Treating Tobacco Use and Dependence indicates that medications (e.g., nicotine replacement therapies, bupropion, varenicline) and counseling are both effective but more effective when combined. Adding smoking cessation counseling (problem solving, skills training, social support) to medications increases the chance of quitting by 40%. More counseling sessions lead to better outcomes, but even low intensity counseling through quitlines (1-800-QUITNOW) increases the chance of quitting by 30% relative to medications alone.
Dietary intake is another major risk factor for heart disease. Reducing the intake of trans-fats, saturated fats, and cholesterol reduces the risk of heart disease. These fats are found most often in processed baked goods (e.g., cakes, cookies, pies) and fried fast foods. Limiting these fats as well as sugar, and eating a heart healthy diet predominately of fruits and vegetables, whole grains, low fat meats and nuts, and low-fat dairy products plays a major role in reducing heart disease risk. A heart healthy diet not only reduces the risk of heart disease directly, but along with reduced portion sizes and physical activity, reduces the risk of obesity, another significant risk factor for heart disease as well as other conditions such as diabetes and metabolic syndrome that further increase the risk of heart disease.
The American Heart Association (AHA) recommends reducing sodium (salt) intake which reduces the risk of hypertension or high blood pressure, a condition that contributes to heart disease risk. The World Heart Federation estimates that if everyone reduced their salt intake by 1g a day, it would lead to a 50% reduction in the number of people needing treatment for hypertension. There is some debate if everyone needs to reduce their daily salt intake or if only those with hypertension or at risk for heart disease should do so. Regardless, it is relatively easy to be attentive to the sodium in processed foods, from which nearly three quarters of our salt intake comes, and select lower sodium alternatives whenever possible.
Physical inactivity doubles the risk of heart disease. Although vigorous exercise (e.g., running, swimming) is more protective, moderate physical activity such as walking substantially reduces the risk of heart disease. Physical Activity Guidelines for Americans recommend that adults do at least 150 minutes a week of moderate-intensity (or 75 minutes a week of vigorous-intensity aerobic physical activity). This activity can be as short as 10 minutes at a time or as infrequently as 3 times per week to obtain some benefit; however, engaging in 30 minutes of activity nearly every day is preferable. Emerging evidence suggests that sedentary behavior also contributes to heart disease risk. A recent AHA Science Advisory reported that adults spend 6-8 hours per day in sedentary activities and that greater sedentary activity is associated with greater risk of cardiovascular disease.
The contributions of behavioral and social sciences extend beyond the questions of if and how these behaviors increase the risk of heart disease to address how to help people modify these behaviors to reduce their risk and live healthier lives. Educating people about what is best for their health is a necessary but not sufficient condition to help them change their behavior. A recent review of behavior change techniques for healthy eating and physical activity in overweight and obese adults concluded that techniques such as goal setting, graded tasks, self-monitoring, and feedback were effective in producing dietary and physical activity change. These techniques are incorporated into various treatment programs to help people change their diet, increase their physical activity, or quit smoking.
Beyond these individual risk factor behaviors, it is important to recognize that social determinants contribute to heart disease as well. The AHA Scientific Statement on Social Determinants of Risk and Outcomes for Cardiovascular Disease concluded that further reductions in heart disease will require addressing the social factors that lead to disparate risk of heart disease across socioeconomic groups. Lower educational attainment and less income are associated with higher rates of heart disease. Those with the lowest levels of social support have twice the risk of death from heart disease as those with high levels of social support. There is considerable racial and ethnic disparity in heart disease. For instance, Blacks are 2 to 3 times more likely to die from heart disease than Whites. Factors such as access to medical care and living in disadvantaged neighborhoods increase the risk of heart disease and premature death from heart disease.
While some of these social factors are more easily modified than others, we know that population-level policies can reduce the risk of heart disease. Bans on smoking in public places were initially proposed to discourage smoking initiation and encourage smokers to quit. As various localities enacted these bans, hospitals in these localities experienced a 15% reduction in hospitalizations for heart attacks in the year following the ban. A recently updated Cochrane review of the empirical evidence found that smoking bans significantly reduce heart disease, particularly heart attacks. As the AHA concluded in its social determinants report, breakthroughs in social science may be more important than breakthroughs in biological science if we are to continue to reduce heart disease morbidity and mortality.