Lifestyle, Not Genetics Causes Most Premature Heart Disease

Results of a recent study suggest lifestyle choices play a greater role than genetics in most cases of premature heart disease.

The study, which was presented at the European Society of Cardiology (ESC) Congress 2019, found evidence that physical inactivity, smoking, high blood pressure, diabetes, and high cholesterol play a greater role than genetics for most patients under 50 with coronary artery disease (CAD).

"In our clinical practice, we often hear young patients with premature heart disease 'seek shelter' and explanations in their genetics/family history," said study author Joao Sousa, cardiologist at Funchal Hospital in Portugal. "However, when we look at the data in our study, these young patients were frequently smokers, physically inactive, with high cholesterol levels and high blood pressure - all of which can be changed."

In order to evaluate how conventional risk factors and genetic risk score impact the appearance of CAD, investigators conducted a case-control study using patients from the Genes in Madeira and Coronary Disease (GENEMACOR) database. A total of 1075 patients were enrolled in the study and 520 healthy individuals were included as controls.

Specific conditions included by investigators included stable angina, heart attack, and unstable angina. The average age of all study participants was 45 years and 87% were men — the average age of the healthy cohort was 44 and 86% were men. 


Investigators assessed modifiable risk factors including physical activity, smoking, high blood pressure, diabetes, and cholesterol levels. Additionally, a genetic risk score was computed using 33 genetic risk variants. Risk scores were evaluated according to number of traditional risk factors.

Upon analysis, 72.6% of patients had 3 or more modifiable risk factors versus 31.2% of the control group (P<0.0001). When compared to patients with no risk factors, patients with 1 risk factor had an OR of 2.79 (1.19-6.53; P=0.015), 2 risk factors corresponded with an OR of 6.87 (3.03-15.57; P<0.0001), and patients with 3 risk factors had an OR 24.17 (10.87-53.73, P<0.0001).

Investigators noted that mean genetic risk score levels were consistently higher in patients with CAD compared with the healthy controls (0.6±0.6 versus 0.4±0.4, P<0.0001, respectively). In a multivariate analysis, genetic risk score proved to be an independent predictor for premature CAD (OR 1.71, CI 95%, 1.25-2.34, P=0.001).

"Our study provides strong evidence that people with a family history of premature heart disease should adopt healthy lifestyles, since their poor behaviors may be a greater contributor to heart disease than their genetics,” Sousa explained. “That means quit smoking, exercise regularly, eat a healthy diet, and get blood pressure and cholesterol levels checked."

This study, “The contribution of genetics to premature CAD through different degrees of lifestyle factors: a matter of relative significance?” was presented at ESC Congress 2019.