Role of Hypercoagulable Studies in Cryptogenic Stroke: A Retrospective Study

Introduction:

Hypercoagulable states are recognized, although uncommon, etiology of ischemic stroke especially in young adults under the age of 40 and children. Currently, there are no specific guidelines related to screening patients for inherited thrombophilia who are diagnosed with ischemic stroke without any identifiable risk factors. Typically, patients to be screened for thrombophilia will have prior unexplained thromboembolic events. We evaluated the association between thrombophilia and cryptogenic stroke and the role of serologic and genetic testing to establish the diagnosis.

Material and methods:

We performed a retrospective study through a review of EHR of patients diagnosed with ischemic stroke at our hospital between 2015- 2019 with laboratory testing for thrombophilia. The primary outcome was to identify any positive association between thrombophilia and cryptogenic stroke. The secondary outcome was to identify any change in clinical management based on thrombophilia testing results.

Results:

Among 35 patients included, who had an average age of 58.5 years ± 16.37 years with 36.6% under the age of 55 and 63.3% above the age of 55. Sex distribution was 40% female and 60%, male. Of 35 patients who had thrombophilia studies ordered, 9 patients had at least one positive thrombophilia test identified but none of them had any resultant change in management. 2 patients had protein C deficiency, 3 patients had protein S deficiency and 4 patients had antithrombin III deficiency, however, they were measured during the acute phase and were not repeated as an outpatient. None of the patients were found to have any Factor V and PT gene G20210A gene mutation. Lupus anticoagulant, antiphospholipid antibodies, homocysteine level were not uniformly tested.

Conclusion:

Only 8% of all patients who had thrombophilia testing had at least one positive study with no change in clinical management. We concluded that there is a poor correlation between inherited thrombophilia and cryptogenic stroke. The majority of our patients who had worked up done were above the age of 55 years who didn't display any symptom of thrombophilia previously. It raises a question of reflexive and inappropriate testing in the absence of clear guidelines for thrombophilia workup in the setting of cryptogenic stroke.