PF705 PATIENTS WITH CHRONIC IMMUNE THROMBOCYTOPENIA (ITP) SHOW IMPAIRED COGNITIVE FUNCTION
Authors: Vladescu C. , Hart A. , Malik A. , Sayed A. , Paul D. , Bhayani J. , Prem Z. , Cooper N. 
Published: June 2019

Background:

Immune thrombocytopenia (ITP) is an autoimmune disease characterised by a platelet count <100 x 109/L. Treatment options include steroids, immune‐modulating drugs, thrombopoietin receptor agonists and splenectomy, aimed at stopping bleeding and avoiding serious bleeding events. Many patients remain asymptomatic despite a low platelet count, however a proportion of patients complain of exhaustion and fatigue which impacts on daily living. The impact on cognitive function in ITP has not been previously reported. The Cambridge Neuropsychological Test Automated Battery (CANTAB) is a software which consists of a series of tasks designed to assess discrete cognitive subdomains. The tests have been developed and validated over the past 30 years and they have been widely used across a range of clinical groups.

Aims:

Identify whether cognitive impairment is present in patients with ITP and if present, establish if it can be correlated to disease parameters such as platelet count, duration of disease or treatment history.

Methods:

45 adult ITP patients (median age = 40.5, range = 19 to 88) with at least one platelet count <30x109/L recruited to the prospective study between 2014 and 2019 were tested using CANTAB Insight to measure patients’ cognitive health across five key domains: executive function, processing speed, attention, working memory and episodic memory. The results were automatically adjusted for age, gender and education, and the scores were displayed in an instant report. The scores for each function were grouped in three categories: below average, average and above average. Nadir platelet counts, duration of disease and treatment histories were compared between groups of patients with below average, average and above average scores across the five cognitive functions. Analysis was performed using Prism v.7 using the one‐way ordinary Anova.

Results:

Of the 45 patients tested, 55.5% scored below average in at least one of the five domains. The most frequently impaired domains were executive function, processing speed and episodic memory, each present in 20% of the ITP patients, while attention impairment was only observed in less than 5% of the patients (Fig1A). Only one patient had below average scores for three domains: executive function, processing speed and working memory. This patient had refractory disease and had received six different types of treatment within 11 months from diagnosis. The rest of the patients showed cognitive impairment in one (37.7%) or two (15.5%) domains. Patients who had received a higher number of treatments were more likely to score below average in executive function tests (adjusted p value 0.0085) (Fig 1B). No other disease parameters were associated with worse cognitive outcome in this pilot study.

Summary/Conclusion:

More than 50% of patients with ITP had below average scores in at least one of the five cognitive domains tested in this study. These findings are similar to the impairment described in patients with multiple sclerosis, hence may reflect the inflammatory nature of ITP. Having a higher number of treatments showed a detrimental effect on executive function but not on any other cognitive domains. Further research is required to elucidate whether executive function impairment is a side effect of the combination of treatments or whether it is associated with a more severe disease pathophysiology. Understanding what causes cognitive impairment and whether this can be prevented or reversed would help improve quality of life for patients with ITP and possibly other autoimmune conditions.

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