Progression of coronary artery calcification: A pilot study

Objective: To describe individual changes in the quantity of coronary arter y calcification (CAC) measured by electron beam computed tomography (CT) an d determine the rate of change in the quantity of CAC during a 3.5-year per iod, Material and Methods: Eighty-eight consecutive participants (51 men at leas t 30 years of age and 37 women at least 40 years of age) from a community-b ased CAC study were invited for a follow-up examination, Established corona ry artery disease risk factors were studied at baseline. CAC score was meas ured by electron beam CT at baseline and follow-up. Results: Of the 88 invited participants, 82 (93%) returned for a follow-up examination. Considerable variation existed among the participants in the e xtent of CAC score change. On average, CAC score increased over time by an estimated 24% each year (P<0.05). The relative increase in CAC score over t ime was significantly lower for older than for younger participants but did not vary significantly by sex. Conclusion: The ability to recruit follow-up participants in this pilot stu dy and to detect significant change in CAC score over time provides evidenc e that electron beam CT is useful for studying progression of CAC in a samp le and may be a valuable procedure for assessing the effectiveness of clini cal interventions designed to retard progression of coronary atherosclerosi s.