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International Urology and Nephrology
https://doi.org/10.1007/s11255-018-1900-3
NEPHROLOGY - ORIGINAL PAPER
Kidney function and cognitive decline in frail elderly: two faces
of the same coin?
Giuseppe Coppolino
1
· Davide Bolignano
2
· Pietro Gareri
5
· Carmen Ruberto
5
· Michele Andreucci
4
·
Giovanni Ruotolo
3
· Maurizio Rocca
5
· Alberto Castagna
5
Received: 25 November 2017 / Accepted: 22 May 2018
© Springer Science+Business Media B.V., part of Springer Nature 2018
Abstract
Background and aims Cognitive and renal impairment are pervasive among elderly frails, a high-risk, geriatric sub-popula-
tion with peculiar clinical characteristics. In a series of frail individuals with non-advanced chronic kidney disease (CKD),
we aimed at assessing the entity of functional, general health and cognitive impairment and the possible relationship between
these types of dysfunction and the severity of renal impairment.
Methods 2229 geriatric subjects were screened for frailty and CKD. Severity of CKD was assessed by eGFR (CKD-EPI
formula). Frailty was established by the Fried Index. Functional, general health and cognitive status were assessed by vali-
dated score measures.
Results Final analysis included 271 frail CKD subjects (162 women, 109 men). Mean eGFR was 64.25 ± 25.04 mL/
min/1.73 m
2
. Prevalence of mild-to-moderate CKD (stage 3–4) was 44%. Twenty-six percent of patients had severe cognitive
impairment, while mild and moderate impairment was found in 7 and 67% of individuals, respectively. All subjects had poor
functional and general health status. Cognitive capacities significantly decreased across CKD stages (p for trend < 0.0001).
In fully adjusted multivariate analyses, cognitive status remained an independent predictor of eGFR (β = 0.465; p < 0.0001).
Conclusions Mild-to-moderate CKD is highly pervasive among frail elderly individuals and the severity of renal dysfunction
is independently correlated with that of cognitive impairment. Future studies are advocated to clarify whether the combina-
tion of kidney and mental dysfunction may portend a higher risk of worsen outcomes in this high-risk population.
Keywords Frailty · CKD · Cognitive · GFR
Introduction
The prevalence of elderly individuals is dramatically
increasing worldwide, posing a challenge of sustainability
for public health systems in view of the wealth of chronic
diseases that associates with human senescence.
Kidney function is affected by ageing and chronic kidney
disease (CKD) is pervasive in the elderly [1]. In the US
population, the prevalence of renal impairment in persons
older than 70 years resulted as high as 15% [2] and in the
third National Health and Nutrition Examination Survey
(NHANES III), 35% of the elderly population had stage 3
CKD [3].
Frail patients are high-risk elderly individuals showing
particular characteristics that may include unintentional
weight loss, self-reported exhaustion, low energy expendi-
ture, slow gait speed and weak grip strength [4, 5].
* Giuseppe Coppolino
gcoppolino@hotmail.it
1
Nephrology and Dialysis Unit, “Pugliese-Ciaccio” General
Hospital, Via Michele Torcia, 4, 88100 Catanzaro, Italy
2
Institute of Clinical Physiology, CNR - Italian National
Council of Research, Reggio Calabria, Italy
3
Geriatric Unit, “Pugliese-Ciaccio” General Hospital,
Catanzaro, Italy
4
Renal Unit, Department of Health Sciences, “Magna
Graecia” University, Catanzaro, Italy
5
Center for Cognitive Disorders and Dementia, Azienda
Sanitaria Provinciale di Catanzaro, Catanzaro, Italy
@Phil_Robichaud
@deepthiw
@JoseServera