The incidence of idiopathic thrombocytopenic purpura among adults: a population‐based study and literature review

Abstract

Published data on the epidemiology of idiopathic thrombocytopenic purpura (ITP) among adults are very limited. We conducted a study of ITP incidence using the General Practice Research Database in the United Kingdom. From 1992 to 2005, there were 840 cases of ITP among adults considering 21 749 623 person-years (PYs) of follow-up, for a crude incidence of 3.9 per 100 000 PYs [95% confidence interval (CI): 3.6, 4.1]. The incidence was higher among women [4.5 per 100 000 PYs (95% CI: 4.2, 4.9)] than men [3.2 per 100 000 PYs (95% CI: 2.8, 3.5)]. Among both women and men, incidence was higher at older ages and in later study years. In a systematic review of previously published literature, incidence of ITP among adults ranged from 1.6 to 2.68 per 100 000 persons per year; prevalence ranged from 9.5 to 23.6 per 100 000 persons. In order to improve the understanding of the disease burden of ITP, future studies should include a clearly defined definition of ITP and focus on well-described source populations that are geographically and ethnically diverse.

A distinctive form of immune thrombocytopenia in a phase 2 study of alemtuzumab for the treatment of relapsing-remitting multiple sclerosis

“…on May 10, 2018. by guest www.bloodjournal.org From reported for the general adult population (0.016-0.039 per 1000 person-years). 6,7 Two potential sources of bias may contribute to this disparity. First, it is conceivable that ITP occurs with greater frequency in patients with RRMS than in the general population, independent of MS therapy.…”

Immune Thrombocytopenia

“…Estimates of the incidence of adult-onset ITP range from approximately 1.6 to 3.9 per 100,000 persons per year, with a prevalence ranging from 9.5 to 23.6 per 100,000 persons, based on diagnostic codes in the UK health registry 5,6 ; estimates based on International Classification of Diseases, 9th revision (ICD-9) codes at hospital discharge in the United States are somewhat lower. 7 However, in light of the vagaries of diagnosis and diagnostic coding, as well as the likelihood that some affected patients may not seek medical attention, the actual frequency of ITP and the number of individuals requiring therapy is uncertain.…”

“…Indeed, several recent studies confirm a female preponderance in young adults, but surprisingly, they also highlight a much higher prevalence among older individuals in whom males and females appear to be equally affected. 5,6 It is not known whether these findings reflect an evolution in disease epidemiology or merely a shift in the way clinicians ascertain and diagnose ITP.…”

Prevalence of Diagnosed Adult Immune Thrombocytopenia in the United Kingdom

“…In published ITP incidence reports, estimates of adult ITP ranged from 1.6-3.9 per 100,000 adults per year in the United States (US), the United Kingdom (UK), and Japan. [13][14][15][16][17][18] Due to the chronic nature of adult ITP 12 and the consequent accumulation of cases in the population, available prevalence estimates are appreciably higher, 12,[19][20][21] ranging from a 1-year prevalence of 9.5 per 100,000 persons 21 to a high of 189.3 per 100,000 persons in a hospital-based study conducted in a US Veterans Administration patient population. 20 …”