Association of Family History With Incidence and Outcomes of Aortic Dissection.

Background: Aortic dissection (AD) is a life-threatening emergency. However, the heritability and association of family history with late outcomes are unclear.

Objectives: The purpose of this study was to evaluate the effect of family history of AD on the incidence and prognosis of AD and estimate the heritability and environmental contribution in AD in Taiwan.

Methods: Both cross-sectional and cohort studies were conducted using Taiwan National Health Insurance database. A registry parent-offspring relationship algorithm was used to reconstruct the genealogy of this population for heritability estimation. The cross-sectional study included 23,868 patients with a diagnosis of AD in 2015. The prevalence and adjusted relative risks (RRs) were evaluated, and the liability threshold model was used to examine the effects of heritability and environmental factors. Furthermore, a 1:10 propensity score-matched cohort comprising AD patients with or without a family history of AD was included to compare late outcomes in the cohort study.

Results: A family history of AD in first-degree relatives was associated with an RR of 6.82 (95% confidence interval [CI]: 5.12 to 9.07). The heritability of AD was estimated to be 57.0% for genetic factors, and 3.1% and 40.0% for shared and nonshared environmental factors, respectively. After excluding individuals with Marfan syndrome or bicuspid aortic valve, a family history of AD was associated with an RR of 6.56 (95% CI: 4.92 to 8.77) for AD. Furthermore, patients with AD and a family history of AD had a higher risk of later aortic surgery than those with AD without a family history (subdistribution hazard ratio: 1.40; 95% CI: 1.12 to 1.76).

Conclusions: A family history of AD was a strong risk factor for AD. Furthermore, patients with AD with a family history of AD had a higher risk of later aortic surgery than those with no family history of AD.