The risk for venous thromboembolism and cardiometabolic disorders in offspring from thrombosis-prone pedigrees

Background: Most family studies on venous thromboembolism (VTE) have focused on first-degree relatives. Objectives: We took a pedigree-based approach and examined the risk of VTE and cardiometabolic disorders in offspring from extended pedigrees according to the densities of VTE in pedigrees. Methods: From the Swedish population, we identified a total of 482 185 pedigrees containing a mean of 14.2 parents, aunts/uncles, grandparents, and cousins of a core full sibship that we termed the pedigree offspring (n = 751 060). We then derived 8 empirical classes of these pedigrees based on the density of cases of VTE. The risk was determined in offspring for VTE and cardiometabolic disorders as a function of VTE density in their pedigrees. Bonferroni correction for multiple comparisons was performed. Results: VTE was unevenly distributed in the population; the Gini coefficient was 0.59. Higher VTE density in pedigrees was associated in the offspring with a higher risk of pregnancy-related VTE, unusual thrombosis, and superficial thrombophlebitis), thrombophilia, and lower age of first VTE event. Moreover, VTE density in pedigrees was significantly associated in the offspring with obesity, diabetes, gout, varicose veins, and arterial embolism and thrombosis (excluding brain and heart). No significant associations were observed for retinal vein occlusion, hypercholesterolemia, hypertension, coronary heart disease, myocardial infarction, ischemic stroke, atrial fibrillation, heart failure, primary pulmonary hypertension, cerebral hemorrhage, aortic aneurysm, peripheral artery disease, and overall mortality. Conclusion: Offspring of pedigrees with a high density of VTE are disadvantaged regarding VTE manifestations and certain cardiometabolic disorders.