Familial Aggregation of Early-Onset Myocardial Infarction

Abstract

Although ischemic heart disease tends to cluster in families, previous studies have reported a modest (2-fold increased risk) to strong (10-fold increased risk) contribution of family history to the explanation of disease occurrence. The authors assessed the familial aggregation of early-onset myocardial infarction in 11,307 adults aged <65 years who participated in the Third National Health and Nutrition Examination Survey. Logistic regression was used to obtain odds ratios (ORs) and 95% confidence intervals (CIs). A parental history was more common in those with (n = 237) than in those without (n = 11,070) a myocardial infarction (19.8 vs. 7.9%, p ≤ 0.01). Adults with a parental history were also more likely to have multiple risk factors for cardiovascular disease (OR for four or five risk factors compared with none: 2.9, 95% CI: 1.4, 6.3). After multivariate adjustment, the likelihood of myocardial infarction was more than three times greater among adults with a parental history than among those without (95% CI: 1.7, 6.7). A maternal history of myocardial infarction was strongly associated (OR = 6.1, 95% CI: 2.1, 17.4) with an increased likelihood of myocardial infarction, and a paternal history was associated with a 3-fold (95% CI: 1.5, 6.3) increased likelihood of myocardial infarction after adjustment for cardiovascular disease risk factors. These results suggest a familial aggregation of early-onset myocardial infarction and show that family history is strongly associated with cardiovascular disease risk factors.

Relative Familial Clustering of Cerebral Versus Coronary Ischemic Events

“…The population-based approach to assessment of heritability 20,21 is less prone to ascertainment bias than the "extended family" approach, which concentrates on families with high incidence of disease. 19,20 However, very few populationbased studies have ascertained both coronary and cerebral events.…”

Expanding the definition of a positive family history for early-onset coronary heart disease

“…3,[7][8][9][10]14,25,26 Studies that have investigated family history of late-onset disease have found positive associations with CHD, although comparatively the relative risks are smaller. [7][8][9][10]25,26 We found significant increases in early-onset CHD given early-onset CHD in either first-or second-degree relatives. Late-onset CHD in first-degree relatives was also significantly associated with early-onset CHD; however, the strength of association was reduced by half, 5.0-fold versus 2.5-fold increase, respectively.…”

“…Many studies have found a two-to threefold increase in CHD given a first-degree relative with CHD, [3][4][5][6] and the strength of this association increases as the number of affected first-degree relatives increases 7,8 and with younger ages of CHD onset in relatives. [7][8][9][10] Less is known about the effects of later-onset CHD in relatives, second-degree relatives with CHD, or the presence of stroke and diabetes among relatives. Furthermore, few studies have assessed the impact of the type of relative affected with CHD (e.g., parent or sibling) or the lineage of affected relatives (i.e., maternal or paternal) on CHD risk.…”

Familial risk assessment for early-onset coronary heart disease

“…1,[5][6][7]9,[11][12][13] Studies that have investigated family histories of late-onset CHD have also found significant positive associations with CHD, although the relative risks are comparatively smaller. 5,6,9,[11][12][13] Recent studies have demonstrated an increased CHD risk associated with CHD in second-degree relatives, 14,15 and in maternal relatives, 13 although other studies have not found an association between CHD and lineage. 4,7,10,16 Despite the importance of family history as a CHD risk factor, it is underused in CHD prevention efforts.…”