CAC of Zero: Maintaining a Low Customer Acquisition Cost
Calcium Score Testing: A Divide on Early Screening for Heart Disease
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A recent analysis of teh Multi-Ethnic Study of Atherosclerosis (MESA) data has reignited debate among cardiologists regarding the optimal age for Coronary Artery Calcium (CAC) scoring, a non-invasive imaging test that detects calcified plaque in the arteries.While the study highlights the prognostic power of CAC scores,experts remain divided on whether to recommend routine screening at younger ages.
The Predictive Power of CAC Scores
The MESA data, published in 2015, demonstrated a meaningful correlation between CAC scores and the risk of atherosclerotic cardiovascular disease (CVD). According to Dr. Shah, CAC scores exceeding 100 were associated with a seven- to tenfold increase in CVD risk.Conversely, a CAC score of 0 indicated a favorable prognosis, with a 4.5% lower rate of events than predicted.
A secondary analysis of the MESA data further explored the implications of a zero CAC score. It revealed that among younger participants, maintaining a CAC score of 0 was linked to a reduced risk of future CVD problems, notably when considering baseline cardiovascular health factors such as diet quality, cholesterol levels, blood pressure, and fasting glucose. Though, this association was not observed in individuals over the age of 65.
The Question of Early Screening
The findings raise a crucial question: does the data support testing for CAC at a relatively young age? Dr. Shah expressed hesitation, stating, “I do not think that a baseline calcium score in young individuals in the 30s or early 40s is likely to be clinically useful.” He reasoned that the prevalence of CAC scores greater than 0 is very low in this demographic, and widespread screening could lead to unnecessary radiation exposure without significant diagnostic yield.
A Counterpoint: The Case for Earlier Testing
Dr. Matthew Budoff, a professor of medicine at the University of California Los Angeles and an endowed chair of preventive cardiology at the Lundquist Institute, offered a differing perspective. He pointed to existing guidelines that recommend CAC testing for individuals with a family history of CVD as early as 38 years old for men and around 48 years old for women, citing validation from large consortium studies.
Dr. Budoff also challenged the concern over radiation exposure, comparing the dose from a CAC scan to that of a mammogram, which is widely accepted for early breast cancer detection. He emphasized that heart disease claims considerably more lives annually than breast cancer.
Guiding Treatment Decisions
According to a state-of-the-art review on CAC guidelines co-authored by Dr. Budoff, a common consensus is that CAC scoring is valuable for refining risk stratification. It can help up- or down-classify patients whose risk is assessed using conventional factors like elevated blood pressure or glucose. A high CAC score may prompt more aggressive treatment in individuals with moderate elevations in traditional risk factors, while a low score can signal a reduced risk of events, even in those with concerning factors like a family history.
While Dr. Shah’s study implies the benefit of identifying a CAC score of 0 and implementing strategies to maintain cardiovascular health, this specific benefit has not been definitively established by his research.Dr. Budoff,while not commenting directly on the implications of a zero CAC score,reiterated the utility of elevated CAC in conjunction with other risk factors to guide the intensity of interventions,particularly for patients with intermediate risk based on conventional variables.
Aggressive Therapy for Elevated Scores
Dr. Budoff highlighted that while the genetic underpinnings of elevated CAC scores are not fully understood, the phenotype of increased arterial calcification is well-defined. He advocated for “aggressive therapy” when a patient’s calcium score is above the 75th percentile for their age and sex, especially in the presence of major CVD risk factors.
Both Dr. Shah and Dr. Budoff reported no relevant financial conflicts of interest.