From this paper (Radiol Bras. 2017 May-Jun; 50(3): 182–189. doi: 10.1590/0100-3984.2015.0235. Coronary artery calcium score: current status. Priscilla Ornellas Neves, Joalbo Andrade, and Henry Monção):
The CAC score is an independent marker of risk for cardiac events, cardiac mortality, and all-cause mortality. In addition, it provides additional prognostic information to other cardiovascular risk markers.
The well-established indications for the use of the CAC score include stratification of global cardiovascular risk for asymptomatic patients: intermediate risk based on the Framingham risk score (class I); low risk based on a family history of early CAD (class IIa); and low-risk patients with diabetes (class IIa).
In symptomatic patients, the pre-test probability should always be given weight in the interpretation of the CAC score as a filter or tool to indicate the best method to facilitate the diagnosis. Therefore, the use of the CAC score alone is limited in symptomatic patients.
In patients with diabetes, the CAC score helps identify the individuals most at risk, who could benefit from screening for silent ischemia and from more aggressive clinical treatment.
See also (J Am Coll Cardiol. 2009 Jan 27; 53(4): 345–352. Coronary calcium predicts events better with absolute calcium scores than age-gender-race percentiles – The Multi-Ethnic Study of Atherosclerosis (MESA).
Matthew J Budoff, et.al.).
Expressing CAC in terms of age and gender specific percentiles had significantly lower area under the ROC curve(AUC) than using absolute scores (women: AUC 0.73 versus 0.76,p=0.044; men: AUC 0.73 versus 0.77,p<0.001). Akaike’s information criterion (AIC) indicated better model fit using the overall score. Both methods robustly predicted events(>90th percentile associated with a hazard ratio(HR) of 16.4(95% c.i. 9.30,28.9), and score >400 associated with HR of 20.6(95% c.i. 11.8, 36.0).
Within groups based on age/gender/race/ethnicity specific percentiles there remains a clear trend of increasing risk across levels of the absolute CAC groups.
In contrast, once absolute CAC category is fixed, there is no increasing trend across levels of age/gender/race/ethnicity specific categories.
Patients with low absolute scores are low risk, regardless of age-gender-ethnicity percentile rank.
Persons with an absolute CAC score of >400 are high risk, regardless of percentile rank.
I am interested in getting my CAC score to see what damage years of diabetes and hypertension may have done to me.