Sibling Cardiovascular Disease as a Risk Factor for Cardiovascular Disease in Middle-aged Adults

Abstract

Cardiovascular disease (CVD) in a first-degree relative confers increased risk for CVD,¹ but whether familial CVD is truly an independent risk factor remains controversial. Parental CVD doubles the risk of CVD in adult offspring.² A seminal report by Marenberg et al³ established increased risk for death from coronary heart disease in twins. Risk associated with CVD in siblings in multiplex families is less certain because published estimates are largely derived from case-control studies that generally lack sibling CVD event validation.^4-6 Furthermore, estimates regarding magnitude of risk associated with a history of sibling CVD vary greatly. Some studies have reported CVD risk similar to that conferred by a history of parental CVD^5,7; others have described much greater CVD risk in relation to sibling history than in relation to parental history.⁶