Introduction: Patients with chronic kidney disease (CKD) are at substantially increased risk of dementia. Clonal hematopoiesis of indeterminate potential (CHIP), caused by clonal expansion of blood cells with somatic mutations in certain driver genes, is an established risk factor for cardiovascular diseases, including cerebral vascular disease. In contrast, CHIP was recently shown to be associated with a decreased risk of Alzheimer’s disease. Given emerging evidence of a key role of vascular compared to neurodegenerative mechanisms in CKD-related dementia, the relation of CHIP with cognitive decline in CKD patients needs clarity. We investigated the prospective associations of CHIP with cognitive impairment in a cohort of patients with CKD. Methods: Our study included 1989 participants aged 65 years or older from the Chronic Renal Insufficiency Cohort. Participants underwent high-depth targeted gene sequencing to ascertain CHIP status. Cognitive function was assessed by four cognitive tests (see Table ). For each test, incident cognitive impairment was defined as a test score one standard deviation worse than the baseline group mean. Sequential Cox proportional hazards models tested associations between CHIP and cognitive impairment after adjusting for demographics (model 1), clinical measures (model 2), and APOE genotype in a subset with available data (model 3). Results: CHIP carriers were significantly less likely to experience impairment in attention (Trails A) and executive function (Trails B) in our fully adjusted models ( Table ). There were no significant associations between CHIP and impairment in global cognition (3MS) or verbal memory (Buschke). There were no differences in the associations of CHIP with cognitive impairment across sex or race groups (data not shown). Conclusions: In patients with CKD, we observed markedly reduced risks of impairment in cognitive domains of attention and executive function. Further studies are needed to confirm our findings and evaluate mechanisms of these relations.
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