Kidney function and cognitive aging and impairment among diverse Hispanic/Latino individuals: Study of Latinos-Investigation of Neurocognitive Aging (HCHS/SOL).

Introduction: The purpose of this study is to examine associations between kidney disease and cognitive impairment among diverse middle-aged and older Hispanic/Latino individuals.

Methods: Between 2016 and 2018, the Study of Latinos-Investigation of Neurocognitive Aging (SOL-INCA) enrolled diverse Hispanic/Latino individuals ages 50 years and older (n = 6377). Cognitive function, cognitive change, and mild cognitive impairment (MCI) were the primary outcomes. Chronic kidney disease (CKD, defined as estimated glomerular filtration rate [eGFR] < 60 mL/min per 1.73 m2 or urine albumin-creatinine ratio [uACR] ≥ 30 mg/g) and two independent secondary exposures (i.e., eGFR and uACR) were examined.

Results: CKD was associated with lower cognitive function and 7-year cognitive decline independent of diabetes and hypertension. CKD was associated with MCI, but the effect attenuated by adjustments for CVD risk factors. More albuminuria was associated with lower cognitive function, cognitive decline, independent of CVD risk factors.

Discussion: CKD and higher albuminuria were linked to lower cognitive function, cognitive decline, and elevated risk for MCI among diverse middle-aged and older Hispanic/Latino individuals.

Highlights: Kidney disease has garnered increased attention in interpreting blood-based biomarkers of Alzheimer's disease and related disorders. Hispanic/Latino individuals are at increased risk for kidney disease. We found that urinary albumin-to-creatinine ratio outperformed estimated glomerular filtration in relation to cognitive function and impairment. Our findings suggest that kidney dysfunction is an independent marker of cognitive function and impairment.