Abstract MP11: Role of Modifiable and Non-Modifiable Risk Factors in the Association of Kidney Function With Dementia Incidence in Multi-Ethnic Study of Atherosclerosis (MESA)

Abstract

Introduction: As many as 20-50% of persons with chronic kidney disease have mild-to-moderate cognitive impairment or overt dementia. Shared risk factors, such as aging, sex, hypertension, and diabetes have been suggested to play a role in this association. Our objective was to examine the contribution of non-modifiable and modifiable risk factors to this association. Hypothesis: We hypothesize that non-modifiable and modifiable risk factors could explain part, but not all, of the association between worse kidney function with incidence of dementia. Methods: We included 6025 CVD free participants (mean age 62 yrs, 51% women, 38% white). Kidney function was assessed by estimated glomerular filtration rate (eGFR) and albumin-to-creatinine ratio (ACR). Participants were followed for an average of 12±4 yrs for dementia ICD code hospitalization. Multiple Cox regression models, adjusted for baseline non-modifiable (age, sex, race, and APOE4 carriership) and modifiable risk factors (BMI, smoking, SBP, diabetes, cholesterol, alcohol intake, education, physical activity, and healthy diet score) were used to estimate the association of worse kidney function with incidence of dementia hospitalization. Results: During follow-up, 268 (4.4%) participants were hospitalized for dementia. Non-modifiable risk factors vs. modifiable risk factors were associated with greater reduction in HRs from a crude model for association between each SD lower eGFR and risk of dementia (70% vs. 8%). Non-modifiable risk factors explained a higher percentage of the association of doubling ACR with risk of dementia than modifiable risk factors (14% vs. 7%) (Figure). Adjusting for all factors, worse kidney function remained associated with incident dementia. Conclusions: Findings suggest that conventional modifiable and non-modifiable risk factors cannot fully explain higher risk of dementia in relation to worse kidney function. This finding warrants exploring other potential novel vascular and nonvascular mechanisms of this association.