Association Between Idiopathic Thrombocytopenic Purpura and Hemorrhagic and Nonhemorrhagic Stroke.

Background: Idiopathic thrombocytopenic purpura (ITP) is characterized by a low platelet count. This may lead to an increased risk of hemorrhagic stroke but a lower rate of nonhemorrhagic stroke. The goal of this study was to evaluate the association between ITP and both hemorrhagic and nonhemorrhagic strokes using a large database.

Methods: We used the Nationwide Inpatient Sample (NIS) database to analyze the occurrence of hemorrhagic and nonhemorrhagic stroke in patients with and without a diagnosis of ITP from 2005 to 2014.

Results: Univariate analysis revealed a higher incidence of hemorrhagic stroke in patients with ITP in the year studied. (for example, in 2005: OR, 1.75; 95% CI, 1.57-1.94; P < 0.001; 2014: OR, 2.19; 95% CI, 2.03-2.36; P < 0.001). After adjusting for age, gender, race, and hypertension, hemorrhagic stroke remained significantly associated with ITP (in 2005: OR, 1.85; 95% CI, 1.49-1.89; P < 0.001; 2014: OR, 2.01; 95% CI, 1.86-2.18; P < 0.001) for all the years studied. Nonhemorrhagic stroke occurred at a lower rate in patients with ITP in most years (2006: OR, 0.91; 95% CI, 0.85-0.97; P = 0.004; 2014: OR, 0.88; 95% CI, 0.83-0.93; P < 0.001). Multivariate analysis confirmed a higher rate of nonhemorrhagic stroke in ITP patients.

Conclusion: Our analysis showed that there was a higher rate of hemorrhagic stroke but a lower rate of ischemic stroke in ITP patients, suggesting an important role of platelets in the occurrence of stroke.