National Stroke Association Guidelines to Prevent Stroke

To the Editor: I found the otherwise laudable review of guidelines on prevention of a first stroke from the NSA¹ lacking in 1 important point. Familial ischemic stroke is a well-known entity² and, although partly explained by familial aggregation of traditional risk factors, clusters of cases in families who appear free of those risk factors do occur. Such cases of cryptogenic stroke should be evaluated for several specific etiologies, including paradoxical embolism and, more importantly, thrombophilia.³ Data suggest that among the many risk factors for stroke under genetic influence,⁴ familial thrombotic coagulopathies can be identified in some cases, in particular activated protein C resistance due to factor V Leiden mutation⁵ and possibly primary antiphospholipid antibody syndrome.⁶ Thus, the NSA recommendations should include the screening of members of families with unexplained stroke aggregation for possible inherited thrombophilia. Once recognized, appropriate prophylactic treatment should be considered.