To conduct the study, researchers collected data from 3,733 volunteers in the Multi-Ethnic Study of Atherosclerosis, who all had systolic blood pressures between 120 and 179. The group was 48 percent men and had an average age of 65.
At the beginning of the study, each participant’s blood pressure was measured and a cardiac CT scan was taken to evaluate their coronary artery calcium scores. The risk of heart disease based on traditional risk factors was also determined for each participant using the Atherosclerotic
Cardiovascular Disease Risk Algorithm. Participants were then classified into three groups based on their coronary artery calcium scores: participants with zero, participants with zero to 100, and participants with 100 or higher. The participants were followed over the course of 10 years and heart disease diagnosis, hospitalizations, and deaths were recorded annually.
Those in the group with a score of zero, but who had a high calculated risk of heart disease according to traditional risk factors, had a low rate of actual events over the 10-year period. In comparison, those who scored in the 100 or greater group but had a low calculated risk of developing heart disease experienced a higher actual event rate. These results demonstrate that, despite traditional risk factors indicating a patient is at high risk for developing heart disease, lower amounts of calcium in the arteries may mean they do not require aggressive blood pressure treatment. Similarly, the findings show that those who are not deemed at risk based on traditional risk factors, but who have high levels of coronary artery calcium, could benefit from more intensive blood pressure treatments.
CT scans can be used to measure the level of calcium in the arteries of the heart, allowing doctors to make specific recommendations on a case by case basis. Patients with high levels of coronary artery calcium could benefit from medication and blood pressure treatment, while those with lower levels may be treated less intensively after considering their individual risk factors. Assistant Professor J. William McEvoy of the Johns Hopkins University School of Medicine commented on the potential benefits of using CT scans, stating “If a healthcare provider wants to target blood pressure in a patient with traditional heart disease risk factors and above-normal blood pressure, he or she can look at coronary artery calcium to help with tiebreaker-like decisions.”
Tailoring treatment to each patient specifically could help reduce the risk of developing heart disease in many whose blood pressure falls in the gray zone of prehypertension. It can also reduce the risk of patients reacting poorly to higher doses of medication that may not be necessary. Some of the side effects associated with many blood pressure medications are sexual dysfunction, dizziness, falls, and weakness. Through assessing the level of coronary artery calcium via CT scans, these side effects could potentially be avoided, increasing the quality of life for some with prehypertension.