Background The Brain in Kidney Disease (BRINK) Study aims to identify mechanisms that contribute to increased risk for cognitive impairment in patients with chronic kidney disease (CKD). We describe the rationale, design, and methods of the study and report baseline recruitment and cognitive function results. Study Design Longitudinal observational cohort study of the epidemiology of cognitive impairment in CKD. The primary aim is to characterize the association between (1) baseline and incident stroke, white matter disease, estimated glomerular filtration rate (eGFR), inflammation, microalbuminuria, and dialysis initiation and (2) cognitive decline over 3 years in a CKD cohort with a mean eGFR < 45 mL/min/1.73 m2. Setting & Participants Community-dwelling participants 45 years or older recruited from 4 health systems into 2 groups: reduced eGFR, defined as eGFR < 60 mL/min/1.73 m2 (non-dialysis dependent), and control, defined as eGFR ≥ 60 mL/min/1.73 m2. Predictor eGFR group. Outcomes Performance on cognitive function tests and structural brain magnetic resonance imaging. Measurements Sequential cognitive and physical function testing, serum and urine biomarker measurement, and brain magnetic resonance images over 3 years. Results Of 554 participants, mean age was 69.3 years; 333, 88, and 133 had eGFRs < 45 (non-dialysis dependent, nontransplantation), 45 to <60, and ≥60 (controls) mL/min/1.73 m2, respectively. Mean eGFR in reduced-eGFR participants was 34.3 mL/min/1.73 m2. Baseline cognitive performance was significantly associated with eGFR in all domains except language. Participants with eGFRs < 30 mL/min/1.73 m2 performed significantly worse than those with eGFRs ≥ 30 mL/min/1.73 m2 on tests of memory, processing speed, and executive function. Participants with reduced eGFRs overall scored worst on the Immediate Brief Visual-Spatial Memory Test-Revised. Limitations Healthy cohort bias, competing risk for death versus cognitive decline. Conclusions Cognitive function was significantly worse in participants with eGFRs < 30 mL/min/1.73 m2. Future BRINK analyses will measure risk factors for cognitive decline using the longitudinal data.
|Original language||English (US)|
|Number of pages||8|
|Journal||American Journal of Kidney Diseases|
|State||Published - Apr 1 2016|
Bibliographical noteFunding Information:
Support: Funding for this work was provided by National Institute on Aging grant R01 AG03755 , Satellite Health Inc, and the Minneapolis Medical Research Foundation. The study sponsors did not play a role in study design; collection, analysis, and interpretation of data; writing the report; or the decision to submit the report for publication.
The authors thank the BRINK Study participants and families for their generous contribution in time and commitment to the study; Rachel Vasseur and Katelyn Hanneman for excellent work in participant recruitment and testing; and Nan Booth, MSW, MPH, ELS, for editing. Funding for this work was provided by National Institute on Aging grant R01 AG03755, Satellite Health Inc, and the Minneapolis Medical Research Foundation. The study sponsors did not play a role in study design; collection, analysis, and interpretation of data; writing the report; or the decision to submit the report for publication.
© 2016 National Kidney Foundation, Inc.
- Cognitive impairment
- brain aging
- chronic kidney disease (CKD)
- estimated glomerular filtration rate (eGFR)
- executive function
- neuropsychological testing
- processing speed
- renal function
- structural brain magnetic resonance imaging
- study design