Objective: We investigated whether the association between family history (FH) for premature coronary artery disease and coronary calcium scores differs according to age.
Methods: We evaluated individuals referred to 128-slice multi-detector computed tomography to measure CAC scores at a single center from 2011 to 2017. Individuals with known CAD or typical angina were excluded. Positive FH was defined as first-degree relatives with early onset CAD (men = 55 years, women = 65 years). High CAC scores were defined as above 100 Agatston or higher than the 75th percentile for age and sex. The participants were divided in two age categories: "Younger age" for men = 55 years old or women = 65 years old, and "Older age" otherwise.
Results: We evaluated 3187 individuals ageing from 18 to 92 years, 54% (n=1721) being categorized as "Younger age". Overall, participants with positive FH (n=759) were younger (56±12 vs 60±13) and more frequently women (54% vs 48%) than those with negative FH. Positive FH was independently associated with high CAC, after adjustment for age, sex, body mass index, smoking status, hypertension, diabetes mellitus, dyslipidemia and sedentary lifestyle. This association was similar between individuals at "Younger age" [Odds Ratio 1.46 (95% Confidence Interval 1.15 - 1.86)] and individuals at "Older Age" [OR 1.65 (95% IC 1.23 - 2.20), p for interaction = 0.79, Figure]
Conclusion: Positive FH for premature CAD was associated with higher CAC scores, independently of other cardiovascular risk factors, and this association was similar between younger and older individuals.