Albuminuria, cognitive functioning, and white matter hyperintensities in homebound elders.
BACKGROUND
Albuminuria, a kidney marker of microvascular disease, may herald microvascular disease elsewhere, including in the brain.


METHODS
Cross sectional.


METHODS
Boston, MA, elders receiving home health services to maintain independent living who consented to brain magnetic resonance imaging.


METHODS
Urine albumin-creatinine ratio (ACR).


RESULTS
Performance on a cognitive battery assessing executive function and memory by using principal components analysis and white matter hyperintensity volume on brain imaging, evaluated in logistic and linear regression models.


RESULTS
In 335 participants, mean age was 73.4 +/- 8.1 years and 123 participants had microalbuminuria or macroalbuminuria. Each doubling of ACR was associated with worse executive function (beta = -0.05; P = 0.005 in univariate and beta = -0.07; P = 0.004 in multivariable analyses controlling for age, sex, race, education, diabetes, cardiovascular disease, hypertension, medications, and estimated glomerular filtration rate [eGFR]), but not with worse memory or working memory. Individuals with microalbuminuria or macroalbuminuria were more likely to be in the lower versus the highest tertile of executive functioning (odds ratio, 1.18; 95% confidence interval, 1.06 to 1.32; odds ratio, 1.19; 95% confidence interval, 1.05 to 1.35 per doubling of ACR in univariate and multivariable analyses, respectively). Albuminuria was associated with qualitative white matter hyperintensity grade (odds ratio, 1.13; 95% confidence interval, 1.02 to 1.25; odds ratio, 1.15; 95% confidence interval, 1.02 to 1.29 per doubling of ACR) in univariate and multivariable analyses and with quantitative white matter hyperintensity volume (beta = 0.11; P = 0.007; beta = 0.10; P = 0.01) in univariate and multivariable analyses of log-transformed data. Results were similar when excluding individuals with macroalbuminuria.


CONCLUSIONS
Single measurement of ACR, indirect creatinine calibration, and reliance on participant recall for elements of medical history.


CONCLUSIONS
Albuminuria is associated with worse cognitive performance, particularly in executive functioning, as well as increased white matter hyperintensity volume. Albuminuria likely identifies greater brain microvascular disease burden.
Weiner
Daniel E
DE
Division of Nephrology, Tufts Medical Center, Boston, MA 02111, USA. dweiner@tuftsmedicalcenter.org
Bartolomei
Keith
K
Scott
Tammy
T
Price
Lori Lyn
LL
Griffith
John L
JL
Rosenberg
Irwin
I
Levey
Andrew S
AS
Folstein
Marshal F
MF
Sarnak
Mark J
MJ
D000368:Aged; D000419:Albuminuria / Q000150:complications*; D003072:Cognition Disorders / Q000209:etiology*; D003430:Cross-Sectional Studies; D005260:Female; D018577:Homebound Persons; D006801:Humans; D008297:Male