By John A. Rumberger, PhD, MD, FACC, FSCCT
Director of Cardiac Imaging at The Princeton Longevity Center
Computed Tomographic (CT) Calcium Testing Facilitates Informed Patient Choices
A new study was published in the October 13, 2015 issue of the Journal of the American College of Cardiology. 1 This study – involving CT calcium testing in a large patient population – has potential to significantly refine conventional wisdom regarding long-term statin therapy for cholesterol, as well as favorably impact and lower medical costs and provide more flexible treatment options for high cholesterol.
Statin prescription medication [e.g. Lipitor, Pravachol, Crestor, etc.] for high cholesterol has been shown to be very beneficial in broadly lowering cardiac risk across a number of populations; but the issue is that the medications may not be appropriate for all patients with high cholesterol.
The most recent American College of Cardiology (ACC)/American Heart Association (AHA) guidelines for cholesterol management have essentially significant expanded the numbers of potential candidates eligible for statin therapy. This has stirred a lot of controversy in medicine with primary care doctors in particular not sure who to advise or prescribe statin therapy to or to advise on diet and lifestyle alone. The study noted above has found that nearly half of persons with risk high enough to merit statin treatment (according to current guidelines) can be reclassified to a level where they are not recommended for such therapy after a non contrast cardiac CT coronary calcium scan [a.k.a. – a HeartScan]
These new data in a very large cohort confirms CAC also to discriminate those at a low risk of events, potentially allowing for de-identification of therapy. Experts suggest that this will reduce costs and potential downstream side effects of medical therapy in patients highly unlikely to benefit from such treatments using statins.
The study’s primary author, Khurram Nasir, MD, MPH of the Healthcare Advancement & Outcomes, Miami Cardiac & Vascular Institute, Baptist Health South Florida), commented “this study could significantly impact the physician-patient shared decision process regarding statin initiation for managing cardiovascular risk. Since the majority [of such individuals] are already candidates for statin therapy according to guidelines, the need to identify additional individuals for testing and preventive treatment becomes less compelling. Informed patients place high value on information that potentially reduces or eliminates unnecessary medications. The study results will facilitate patients to engage in shared decisions with their physicians and make informed choices as to optimal risk-reducing treatments individualized to their clinical risk. We believe these risk-guided approaches can limit overtreatment at the population level.”
Dr. Nasir continued by stressing that “perhaps the most profound finding of this study is the realization that in 2015, the true value of CAC testing can be unlocked by emphasizing more of the power of zero. Importantly, for providers reading this report, most of their patients will have no CAC, i.e., a score of zero. We welcome further discussion on the pros and cons of this pragmatic approach, with the goal of empowering our patients through a much better understanding of their underlying risk and subsequent treatment options.”
To summarize the studies major findings:
- Nearly 2/3 of adults aged 45-75 years are either recommended or considered for statins by current guidelines.
- Almost half of these candidates have no coronary artery calcium, and their actual risk is much lower than the threshold suggested by the guidelines to consider statin therapy. The greatest reclassification was noted in those at intermediate level of estimated risk by traditional risk factors.
- The knowledge of significantly lower reclassified risk with absence of coronary artery calcium can be valuable in better informing patients of choices, who may consider avoiding statins to focus on prudent lifestyle changes.
- From a societal prospective, the estimated number of individuals to treat in order to prevent one cardiac event is very high. This finding should stimulate dialogue on best strategies for appropriate resource allocation in the healthcare system.
Dr. John A. Rumberger, PhD, MD, FACC, FSCCT – Director of Cardiac Imaging The Princeton Longevity Center comments:
At the Princeton Longevity Center we feel that it is necessary to define absolute cardiovascular ‘risk’ in a given person/client/individual. That is why all patients at least get a non-contrast CT CAC [coronary artery calcium] scan to estimate their individual coronary ‘atherosclerotic plaque burden’. We use this information to then determine if further testing [such as Cardiac CT Coronary Angiogram – also available] is necessary and to design the prevention and lifestyle plans and whether statin therapy is appropriate. The above study further emphasizes the use of CAC scanning to assist physicians in counseling their patients on risk versus benefit.