Statins and Your Calcium Scores

A woman sitting on a park bench with heart pain

Charday Penn / Getty Images

 A “calcium scan” is an X-ray technique to assess the amount of calcium deposits in the coronary arteries. The presence of calcium in the coronary arteries indicates that atherosclerosis is present. Further, the calcium score (which estimates the amount of calcium in the arteries) roughly corresponds to the severity of coronary artery disease, as follows:

  • 0: no identifiable disease
  • 1 to 99: mild disease
  • 100 to 399: moderate disease
  • 400 or higher: severe disease

Healthcare providers sometimes use the calcium score to help decide whether to recommend treatment with a statin. Statins often reduce the risk of heart attacks.

However, seemingly paradoxically, sometimes the calcium score increases with statin therapy. The tendency of the coronary artery calcium score to increase with statin therapy has been an area of controversy and concern among cardiologists.

As it turns out, at least some evidence now suggests that this may be a good thing. It may indicate that the statins are stabilizing coronary artery plaques.

Some Background

Atherosclerosis produces plaques in the walls of arteries, including the coronary arteries. These plaques can grow large enough to partially obstruct the artery and produce symptoms, such as angina or claudication. However, the real problem with these plaques is that they can suddenly rupture, causing a sudden occlusion of the artery—which often leads to a heart attack or a stroke.

Plaques are deposits of several materials, including lipids, inflammatory cells, fibrotic cells, and calcium. It is the calcium in atherosclerotic plaques that is detected by a cardiac calcium scan—the higher the calcium score, the more extensive is atherosclerosis.

So, for example, if your healthcare provider started you on atorvastatin, he or she was not merely treating your cholesterol levels but was also treating your atherosclerotic plaques.

Statins and the Calcium Score

Several studies have now shown that treating a patient who has atherosclerosis with statins can increase the cardiac calcium score.

Since statins are thought to help prevent and even to help reverse coronary artery disease, this result seems paradoxical. In 2015, a study was published in the Journal of the American College of Cardiology which helps to clarify what this increase in calcium means.

Investigators reviewed eight separate studies which had used intravascular ultrasound (IVUS, a catheter technique) to assess the size and composition of atherosclerotic plaques in patients treated with statins. They found two things. First, high-dose statin therapy tended to shrink plaques.

Second, while the plaques were shrinking, their composition was changing. After statin therapy, the volume of lipid deposits within plaques diminished, and the volume of fibrotic cells and calcium increased. These changes—converting an unstable “soft” plaque to a more stable “hard” plaque—may render a plaque less prone to sudden rupture. (This postulate is consistent with the fact that statin therapy significantly reduces the risk of heart attacks in patients with coronary artery disease.)

Evidence supports the idea that statin therapy not only reduces cholesterol levels but also changes existing plaques to make them less dangerous. As part of this process, the plaques may become more calcified—and thus, calcium score goes up. An increasing calcium score with statin therapy, therefore, may indicate treatment success, and should not be a cause for alarm.

While this theory is not settled science, at this point it best fits the available evidence.

A Word From Verywell

A cardiac calcium scan can be a useful tool in assessing the presence or absence of coronary artery disease. If calcium is present, atherosclerosis is present—and aggressive lifestyle changes are in order. In addition, strong consideration should be given to statin therapy and prophylactic aspirin.

But, once statin therapy has begun, interpreting subsequent calcium scans becomes a problem. If the calcium score goes up, it may not indicate worsening CAD, but rather, is likely to be a positive effect of statin treatment.

As a general rule, healthcare providers should not order tests that they know ahead of time they probably will not be able to interpret. While a screening calcium scan makes a lot of sense for people who are at some risk for coronary artery disease, repeating those calcium scans after statin therapy has been initiated may just create anxiety, without adding any useful information.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Galper BZ, Wang YC, Einstein AJ. Strategies for primary prevention of coronary heart disease based on risk stratification by the ACC/AHA lipid guidelines, ATP III guidelines, coronary calcium scoring, and c-reactive protein, and a global treat-all strategy: a comparative--effectiveness modeling study. PLoS ONE. 2015;10(9):e0138092. doi:10.1371/journal.pone.0138092

  2. Grundy SM, Stone NJ, Bailey AL, et al. 2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA guideline on the management of blood cholesterol: A report of the American College of Cardiology/American Heart Association task force on clinical practice guidelinesCirculation. 2019;139:e1082–e1143. doi:10.1161/CIR.0000000000000625

  3. Lee D, Joo HJ, Jung HW, Lim DS. Investigating potential mediator between statin and coronary artery calcificationPLoS One. 2018;13(9):e0203702. doi:10.1371/journal.pone.0203702

  4. National Heart, Lung, and Blood Institute (NHLBI). Atherosclerosis.

  5. Desai MY, Cremer PC, Schoenhagen P. Thoracic aortic calcification: diagnostic, prognostic, and management considerations. JACC Cardiovasc Imaging. 2018;11(7):1012-1026. doi:10.1016/j.jcmg.2018.03.023

Additional Reading

By Richard N. Fogoros, MD
Richard N. Fogoros, MD, is a retired professor of medicine and board-certified in internal medicine, clinical cardiology, and clinical electrophysiology.