BMSEHA15
Published online 9 February 2010
(Haematologica 2010, 10.3324/haematol.2009.018390)
Copyright © 2010 by Ferrata Storti Foundation
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Google Scholar
Right arrow Articles by Sarpatwari, A.
Right arrow Articles by Provan, D.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Sarpatwari, A.
Right arrow Articles by Provan, D.

Article

Thromboembolic events among adult patients with primary immune thrombocytopenia (ITP) in the United Kingdom General Practice Research Database

Ameet Sarpatwari1,2, Dimitri Bennett3, John W. Logie4, Amit Shukla3, Kathleen J. Beach5, Adrian Newland2, Simon Sanderson1, Drew Provan2

1 Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
2 Department of Haematology, Barts and The London School of Medicine and Dentistry, Whitechapel, London, UK
3 Oncology Epidemiology, Research and Development, GlaxoSmithKline, Collegeville, PA, USA
4 Worldwide Epidemiology, Research and Development, GlaxoSmithKline, Greenford, UK
5 Worldwide Epidemiology, Research and Development, GlaxoSmithKline, RTP, NC, USA

Correspondence: Ameet Sarpatwari, Department of Public Health and Primary Care, University of Cambridge, Cambridge, CB2 0SR, UK. Phone: international +440.203.2460230. Fax: international +440.203.2460351. E-mail: avs31{at}medschl.cam.ac.uk

ABSTRACT

Background: The risk of thromboembolic events (TE) in adults with primary immune thrombocytopenia (ITP) has been minimally investigated despite findings of increased susceptibility in other thrombocytopenic autoimmune conditions. The objective of this study was to evaluate the risk of TE among adult patients with and without primary ITP in the UK General Practice Research Database (GPRD).

Design and Methods: Using the GPRD, 1,070 adults ( 18 years) with coded records for primary ITP first referenced between January 1st 1992 and November 30th, 2007 and having at least one year pre-diagnosis and three months post-diagnosis medical history were matched (1:4 ratio) with 4,280 primary ITP-disease free patients by age, gender, primary care practice, and pre-diagnosis observation time. The baseline prevalence and incidence rate (IR) of TE were quantified, with comparative risk modeled by Cox proportional hazards regression.

Results: Over a median 47.6 months of follow-up (range: 3.0–192.5 months), adjusted hazard ratios of 1.58 (95% CI, 1.01–2.48), 1.37 (95% CI, 0.94–2.00), and 1.41 (95% CI, 1.04–1.91) were found for venous, arterial, and combined (arterial and venous) TE respectively when comparing the primary ITP cohort with the primary ITP-disease free cohort. Further event categorization revealed an elevated IR for each occurring venous thromboembolic subtype among the adult patients with primary ITP.

Conclusions: Patients with primary ITP are at increased risk for venous TE compared with patients without primary ITP.