We know smoking causes lung cancer, and that certain foods are better for our bodies in the long run than others. We have pretty accurate ways to detect tumors and bacteria, and we’ve gotten good at retroactively identifying the causes of our health problems. Though we’ve made incredible strides in the world of medical technology, something that has always eluded our grasp is the ability to tell the future.

Sure, we can catch problems early on with X-rays and checkups and the plethora of other preventive care options available in modern society. We can look at a terminal patient and estimate the time they have left. But never before could we take a perfectly healthy person and tell them with relative certainty that, within 15 years, they were going to die.

According to the results of a study published in the Annals of Internal Medicine, we could have recently gotten much closer to doing just that. A simple coronary artery calcification (CAC) scan may be able to identify if patients are at risk of dying within the next 15 years, according to researchers.

A CAC scan is an X-ray test that looks for specks of calcium in the walls of coronary arteries. These specks are called calcifications, and can be an early indication of coronary artery disease.

Professor Leslee Shaw, of Emory University School of Medicine, collected and analyzed CAC scan data from 9,715 study participants from between 1996 and 1999. The participants were part of a community-outreach program at an outpatient clinic, and showed no signs of coronary artery disease at the time of the scans.

Researchers found that the patients’ scores on the CAC scan accurately predicted who would die from an early death within 15 years. The most astonishing part is, the calcium scores predicted early deaths of all causes, not just deaths due to coronary heart disease.

"These findings give us a better understanding of the importance of coronary calcium scans to predict mortality," said Shaw in a press release.

CAC scans have been used in the past to help estimate patient prognoses in the short-term, but Shaw says that the long-term analysis of this study is unique. Previous studies intending to use scans as indicators of a person’s long-term health have had a follow-up of five years or less.

"Patients with high calcium scores might be advised by their physicians to adopt healthier lifestyles, which could lead to better outcomes and potentially help lengthen their lives,” Shaw said.

Source: Shaw L, "Long-Term Prognosis After Coronary Artery Calcification Testing in Asymptomatic Patients: A Cohort Study." Annals of Internal Medicine. 2015.