Abstract 4117: Age and Risk Factor Profile Modify the Relationship between Family History of Myocardial Infarction and Subclinical Atherosclerosis
Background: A family history of myocardial infarction (FHMI) is an independent risk factor for cardiovascular (CV) disease, but it may be more informative in certain subgroups. We sought to determine if FHMI utility is influenced by age and concomitant risk factors.
Methods: We examined the association between a history of myocardial infarction in a first degree relative and the presence of coronary artery calcification (CAC) in various age and risk factor groups in the Dallas Heart Study, a population-based probability sample of subjects age 30–65. Analyses were stratified by age (“young”= men<45 & women<55) and by the presence of ≤1 or ≥2 CV risk factors. Logistic regression analyses were adjusted for traditional CV risk factors, age, sex, and race.
Results: In the overall cohort of 2743 subjects, FHMI was an independent predictor of CAC [adjusted OR 1.3, 95% CI 1.1–1.7], attributable to an independent association between FHMI and CAC in the young [adjusted OR 1.5, 95% CI 1.0–2.1] that was not evident in the older subset [adjusted OR 1.2, 95% CI 0.91–1.6; interaction p-value=0.02]. In the young cohort, the association between FHMI and CAC was particularly robust among those with ≥2 risk factors (FHMI-by-risk factor interaction p-value=0.04) (Figure⇓). In older subjects, FHMI was not associated with CAC for any risk factor category (p>0.05 for each).
Conclusion: A FHMI is more closely associated with subclinical atherosclerosis in young compared with older adults, and among the young, in those with multiple CV risk factors Aggressive prevention efforts may be warranted for young subjects with FHMI and multiple CV risk factors.