Association of Cognitive Impairment with Reduced Health-Related Quality of Life and Depression Among Survivors of Thrombotic Thrombocytopenic Purpura

Background: Immune-mediated thrombotic thrombocytopenic purpura (iTTP) survivors exhibit increased rates of psychological comorbidities, cognitive impairment (CI), and reduced health-related quality of life (HRQoL). This cross-sectional study investigated the prevalence of CI and its association with reduced HRQoL and depression among iTTP survivors. Methods: iTTP survivors completed the Beck Depression Inventory (BDI-II), the SF-36 for evaluation of HRQoL, and the NIH Toolbox Cognition Battery. SF-36 scores and fluid cognition and crystallized cognition composite scores from the cognition battery were compared to the reference population. We examined associations of cognitive impairment with depression and HRQoL. Results: We enrolled 47 patients with iTTP; 76.6% were female, the median age was 51 (IQR 39, 60), and the median number of episodes was 2 (1, 3.5). Compared to the reference, iTTP survivors had significantly lower mean scores in seven SF-36 domains (physical function, physical limitation, general, mental health, vitality, social functioning, and emotional limitation) as well as the mental component score (MCS) (p < 0.0001) and physical component scores (PCS) (p < 0.0001). A lower physical HRQoL score was observed in those with mild (49.3 vs. 37.7, p = 0.005) and major (49.3 vs. 38.4, p = 0.007) CI compared to no CI. The fluid cognition composite score correlated strongly with the SF-36 Physical Component Summary (r = 0.548, p = 0.0002) but not the Mental Component Summary (r = 0.113, p = 0.489). Conclusions: Cognitive impairment in iTTP survivors is associated with reduced physical HRQoL. Identifying and addressing cognitive deficits in iTTP may improve HRQoL. Given that 40% of participants had depressive symptoms, which were associated with reduced mental HRQoL, iTTP survivors may also benefit from routine mental health screening t.