Association between family history and coronary heart disease death across long-term follow-up in men: the Cooper Center Longitudinal Study

Abstract

Background: Family history of coronary heart disease (CHD) has been well studied as an independent risk factor for CHD events in the short term (<10 years). However, data are sparse on the association between family history and risk for CHD across long-term follow-up.

Methods and results: We included 49 255 men from the Cooper Center Longitudinal Study. Premature family history of CHD was defined as the presence of angina, myocardial infarction, angioplasty, or bypass surgery in a relative <50 years of age. Cause-specific mortality was obtained from the National Death Index. The association between premature family history and cardiovascular disease (CVD) or CHD death was compared across 3 unique follow-up periods (0-10, >10-20, and >20 years). Lifetime risk was estimated by use of a modified survival analytic technique adjusted for competing risk with non-CVD death as the competing event. After 811 708 person-years of follow-up, there were 919 CHD deaths and 1456 CVD deaths. After adjustment for traditional risk factors, premature family history was associated with CHD mortality >10 to 20 years (1.59; 95% confidence interval, 1.14-2.22) and >20 years (1.43; 95% confidence interval, 1.05-1.95) with wider confidence intervals at 0 to 10 years (1.32; 95% confidence interval, 0.76-2.31). Similar findings were observed for CVD mortality. Compared with men without a family history of coronary artery disease, premature family history was associated with an ≈50% higher lifetime risk for both CHD and CVD mortality (13.7% versus 8.9% and 21% versus 14.1%, respectively).

Conclusion: Premature family history was associated with a persistent increase in both CHD and CVD mortality risk across long-term follow-up, resulting in significantly higher lifetime risk estimates.

Figure 1

Cumulative incidence of cardiovascular disease (CVD) death adjusted for competing risk (lifetime risk) for men according to family history status at 55 years of age. Family history of premature coronary heart disease (CHD) denotes a CHD event in a first-degree family member before 50 years of age. n=26 447 for patients with attained age ≥55 years.

Figure 2

Cumulative incidence of cardiovascular disease (CVD) death adjusted for competing risk (lifetime risk) for men according to family history status at 45 years of age. Family history of premature coronary heart disease (CHD) denotes a CHD event in a first-degree family member before 50 years of age. n=37 036 for patients with attained age ≥45 years.