Associations of Chronic Kidney Disease Markers with Cognitive Function: A 12-Year Follow-Up Study.

ABSTRACT:

Background

The role of chronic kidney disease (CKD) as a risk factor for cognitive impairment independent of their shared antecedents remains controversial.

Objective

To determine whether kidney damage (indicated by albuminuria) or kidney dysfunction (estimated glomerular filtration rate [eGFR]?<60?ml/min/1.73 m2) predict future (12-year) cognitive function independently of their shared risk factors.

Methods

We studied 4,128 individuals from the 1999/00 population-based Australian Diabetes, Obesity, and Lifestyle (AusDiab) Study who returned in 2011/12 for follow-up cognitive function testing. Albuminuria was defined by urinary albumin:creatinine?3.5 (women) or?2.5?mg/mmol (men). Kidney dysfunction was indicated by eGFR?<60?ml/min/1.73 m2. Cognitive function domains assessed included memory (California Verbal Learning Test [CVLT]) and processing speed (Symbol Digit Modalities Test [SDMT]).

Results

Baseline albuminuria and kidney dysfunction were identified in 142 (3.4%) and 39 (0.9%) individuals, respectively, with minimal overlap (n?=?7). Those with albuminuria demonstrated concurrently reduced 12-year SDMT (p?=?0.084) and CVLT scores (p?=?0.005) following adjustment for age, sex, and education. However, only CVLT performance remained worse (p?=?0.027) following additional adjustment for myocardial infarction, stroke, and related risk factors (hypertension, diabetes, dyslipidemia, smoking, BMI, physical activity, and alcohol intake). Indeed, these collective covariates were responsible for 47% of the effect of albuminuria on SDMT, but only 21% of its effect on CVLT. Kidney dysfunction was not associated with either SDMT or CVLT performance (p?>?0.10).

Conclusions

Albuminuria predicted worse memory function at 12 years follow-up, whereas its effect on processing speed was driven largely by differences in cardiovascular risk. Kidney dysfunction based on eGFR predicted neither cognitive domain.

SUBMITTER: Sacre JW 

PROVIDER: S-EPMC6700620 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature