Abstract 339: High Prevalence of Coronary Artery Calcification in Asymptomatic First-Degree Relatives of Patients With Known Coronary Artery Disease, Despite Overall Young Age and Low Framingham Risk Score
Introduction. The Framingham Risk Score (FRS) is the current standard for risk stratification in the primary prevention setting; the National Cholesterol Education Panel Adult Treatment Panel III (NCEP III) guidelines are based on the FRS. Family history is an important risk factor for coronary artery disease (CAD) but it is not included in the FRS. We hypothesized that coronary artery calcium (CAC) scanning can reveal atherosclerosis in asymptomatic first-degree relatives of patients with CAD, regardless of FRS score.
Methods. We screened 2 asymptomatic, non-smoking first-degree relatives on no lipid-lowering therapy of 43 patients with CAD using genotyping (Genova Diagnostics), biomarkers and coronary artery calcium (CAC) scanning. Biomarkers were measured with standard enzymatic methods. CAC was done on a multi-slice CT scanner; it was expressed as the Agatston score.
Results. In the relatives, mean age was 41±10. Biomarkers are shown in the Table⇓. In the overall group, FRS was 1.85±1.78; proportion of low, intermediate and high FRS was 98.8%, 1.2%, and 0, respectively. Based on this evaluation, 1 patient (1.2%) would have qualified for lipid-lowering therapy based on NCEP III guidelines. CAC was positive in 19 pts (22%) (median CAC [interquartile range] was 24 [3–99]). Of all patients with positive CAC, 18 (94.4%) were in the low FRS group, 1 (5.6%) in the intermediate and none in the high FRS group. None of the biomarkers predicted positive CAC, but AGT genotype did (Table⇓). 18 patients in the low FRS group would not have qualified for lipid-lowering therapy based on NCEP III guidelines; therefore, CAC scanning changed therapy in a total of 18 pts (20.9%).
Conclusions. While first-degree relatives of patients with CAD are overall young, low-risk and do not qualify for risk-modification based on NCEP III guidelines, 22% had a positive CAC; most of these patients should be considered for lifestyle-changes and pharmaceutical therapy for primary prevention.