heart and stethoscope

Despite marked improvement in some cardiovascular risk factors at the population level in the past 2-3 decades in Europe and North America, cardiovascular diseases (CVD) is still the number one cause of mortality and the prevalence of patients coping with CVD is increasing steadily in these countries. Most of the risk factors for CVD such as smoking, elevated blood pressure and cholesterol, diabetes, obesity, have been identified and are frequently assessed by health professionals. However, emerging evidence also suggest that poor diet and lack of physical activity could and should be considered as CVD risk factors. Yet, these are almost never considered while assessing CVD risk in patients. Studies performed in the United States have documented that assessment of dietary and physical activity habits could be clinically useful but few of these results have been replicated in European countries.

A study just published in the European Journal of Preventive Cardiology shed light on this important issue. Investigators of the EPIC-Norfolk study assessed what the American Heart Association considers “ideal cardiovascular health” in 10,043 study participants without previous CVD from the Norfolk area, United Kingdom (http://cpr.sagepub.com/content/early/2015/09/02/2047487315602015.abstract). In this study ideal cardiovascular health was measured based on dietary factors (intake of fruits and vegetables, fish, fibre-rich whole grains, sodium, sugar-sweetened beverages), leisure-time and work-related physical activity, smoking, body-mass index, cholesterol levels, glycated haemoglobin (a biomarker of diabetes control) and the presence of hypertension. Based on these components, a cardiovascular health score was computed, ranging from 0-2 points (unhealthy) to 12-14 points (healthy or ideal cardiovascular health). These participants were followed for approximately 10 years. The authors found that during the follow-up, 27,3% of participants classified as unhealthy had a cardiovascular outcome while the equivalent number was only 0,7% in participants with ideal cardiovascular health. After considering non-modifiable risk factors such as age and sex, participants with ideal cardiovascular health had a 93% coronary heart disease risk-reduction compared to unhealthy participants. An 84% decreased stroke risk was also observed. Importantly, the authors reported a direct relationship between the number of components of cardiovascular health (the cardiovascular health score) and the risk of stroke and/or coronary heart disease. Unfortunately, only less than 3% of the participants were classified as having ideal cardiovascular health in this population (that represent a fair representation of a typical Western European population).

These findings reinforce the notion that the vast majority of cardiovascular risk factors are modifiable and that many of them are to a significant extent modifiable by lifestyle. This study also highlights that poor lifestyle characterized by low dietary quality and lack of physical activity should be considered as cardiovascular risk factor to the same extent as smoking, high cholesterol and hypertension. This study also highlight that lifestyle related factors, although strongly associated with CVD risk won’t confer much CVD risk reduction if blood pressure and cholesterol are not at optimal levels. It should also be considered that some of the risk factors considered as “modifiable” such as cholesterol and body-mass index have a strong genetic component and despite having a healthy diet and exercising enough, many individuals cannot maintain a cholesterol and/or body mass index in the normal range (<25 kg/m2). Nevertheless, results from the EPIC-Norfolk investigators highlight that the burden of CVD could be substantially reduced if we treated the known risk factors for this disease by encouraging improving diet quality and regular practice of physical activity at the population level and encouraging cardiovascular medications in patients that cannot reach optimal cholesterol and blood pressure levels with lifestyle.