The relative probability of positive family history of CVD among young women diagnosed with VVS (n = 65), age-matched controls with past history of TLOC) (Pos controls, n = 223), and both groups pooled (TLOC pooled) compared with controls without past history of TLOC (n = 326) as a reference. The age-adjusted logistic regression model was applied. Premature CVD was defined as the occurrence of CVD (myocardial infarction or stroke) in a first-degree male relative before the age of 55, or in a first-degree female relative before the age of 65.