Splenectomy in patients with immune (idiopathic) thrombocytopenic purpura (ITP) appears to be protective against developing aortic valve disease.

Background: Immune thrombocytopenia (ITP) has been shown to be independently associated with aortic valve disease (AVD). However, whether ITP patients who have undergone splenectomy are also at increased risk for AVD has not been researched. The goal of this study was to evaluate any association between AVD and splenectomy in patients with ITP.

Method: We used the Nationwide Inpatient Sample from 2005 to 2014 as 10 consecutive years randomly selected. Using ICD-9 codes for AVD, ITP, and splenectomy, a total of 108,434 patients were identified with ITP, 4,282 of which had undergone splenectomy. We performed uni- and multivariate analysis adjusting for baseline characteristics.

Results: Univariate analysis revealed a significantly lower rate of AVD in ITP patients with splenectomy compared to no splenectomy in 2007, 2009, and 2010 with a trend of this association during the other years. For example, in 2007, 0.6% of ITP patients with history of splenectomy had AVD versus 2.0% of ITP patients without splenectomy (OR, 0.29; 95% CI, 0.09-0.91; P = 0.02). Similarly, in 2010, 0.2% of ITP patients with history of splenectomy had AVD versus 1.9% of ITP patients without splenectomy (OR, 0.13; 95% CI, 0.02-0.92; P = 0.02). After adjusting for age, gender, race, diabetes, hypertension, hyperlipidemia, and tobacco use, we confirmed that ITP patients with splenectomy have no association with prevalence of aortic valve disease (2005: OR, 0.48; 95% CI, 0.18-1.30; P = 0.15; 2014: OR, 0.88; 95% CI, 0.36-2.16; P = 0.77).

Conclusion: Based on a large inpatient database, our previous finding of ITP patients' association with AVD is only present in patients without splenectomy, and splenectomy appears to exert a protective effect on developing aortic valve disease in ITP patients, warranting further investigation.