Depression and cognitive impairment following recovery from thrombotic thrombocytopenic purpura

After recovery from an acute episode of acquired thrombotic thrombocytopenic purpura (TTP), patients often describe problems with memory, concentration, and endurance. We have previously reported the occurrence of depression and cognitive impairment in these patients. In this study, we describe the frequency, severity, and clinical course of depression and cognitive impairment. Fifty-two (85%) out of 61 eligible Oklahoma Registry patients who had recovered from TTP, documented by ADAMTS13 activity <10%, have had at least one (median, four) evaluation for depression over 11 years using the Beck Depression Inventory-II; 31 (59%) patients screened positive for depression at least once; in 15 (29%), the results suggested severe depression at least once. Nine of these 15 patients had a psychiatric interview, the definitive diagnostic evaluation; the diagnosis of major depressive disorder was established in eight (89%) patients. In 2014, cognitive ability was evaluated in 33 patients by the Montreal Cognitive Assessment and the Repeatable Battery for Assessment of Neuropsychological Status (RBANS). Both tests detected significant cognitive impairment in the patients as a group. Fifteen out of the 33 patients had been evaluated by extensive cognitive tests in 2006. The 2014 RBANS results were significantly worse than the 2006 results for the overall score and two out of the five RBANS domains (immediate and delayed memory). Neither depression nor cognitive impairment was significantly associated with the occurrence of relapses or ADAMTS13 activity <10% during remission. These observations emphasize the importance of screening evaluations for depression and cognitive impairment after recovery from acquired TTP.