Quantifying cognitive dysfunction across the spectrum of end‐stage kidney disease: A systematic review and meta‐analysis

Abstract

Cognitive dysfunction is reportedly highly prevalent among chronic kidney disease (CKD) patients. A variety of screening tools and neuropsychiatric batteries are used to quantify the magnitude and nature of this dysfunction. Our objective is to summarize the neurocognitive testing used, and determine what degree cognitive dysfunction is reported in CKD patients. All study designs published in English that contained participants who were either pre‐dialysis patients, haemodialysis (HD) or peritoneal dialysis (PD) patients or renal transplant recipients were considered. Reported comparative non‐CKD control data was also collected. All study designs were included. The search period encompassed articles from 1980 to May 2018. This review is registered with PROSPERO (CRD42018096568). Of the 1711 articles screened, 148 articles were relevant and used in the meta‐analysis. Commonly used assessments were The Mini–Mental State Examination (MMSE), The Modified Mini–Mental State Examination, the Trails Making Tests (TMT) forms A and B and components of the Wechsler Adult Intelligence Scale: Digit Span and Digit Symbol. Means for all assessments were adjusted using a random effects model to account for the differences in variance. Adjusted mean MMSE scores were significantly lower for both pre‐dialysis (26.08, n = 17 073) and HD (26.31, n = 3314) patients when compared to non‐CKD controls (28.21, n = 5226). PD (58.01 s, n = 859) and HD (56.04 s, n = 2344) patients also took significantly longer to complete the Trails Making Task A than non‐CKD controls (37.62 s, n = 4809). Patients with CKD, especially pre‐dialysis and those requiring dialysis, are likely to exhibit impairments in cognition that can be identified with specific screening neuropsychological assessments.

Neuropsychiatric Disorders in Chronic Kidney Disease

“…There are several studies investigating cognitive performance across the CKD spectrum, i.e., pre-dialysis CKD patients, patients on renal replacement therapy (hemodialysis or peritoneal dialysis), and transplant recipients for a systematic review, see (Vanderlinden et al, 2019). A recent meta-analysis found that ESRD patients submitted to different modalities of renal replacement therapy have distinct cognitive deficits.…”

“…Both pre-dialysis and patients on hemodialysis exhibited worse global cognition performance in comparison with non-CKD controls, as demonstrated by the significantly lower scores on the Mini-Mental State Examination. Also, patients on peritoneal dialysis or hemodialysis had worse attention/working memory performance, as evaluated by the Trail Making Test-A, than non-CKD controls (Vanderlinden et al, 2019).…”

Neuropsychological and neuroanatomical phenotype in 17 patients with cystinosis

“…However, no major neurocognitive deficits was observed in mild to moderate CKD patients, with eGFR of 30 to 90 ml/mn/ 1.73 m 2 [47,48]. Predialysis patients and dialysis patients are likely to exhibit cognitive impairment [55,56]. Verbal, Performance and Full Score IQs of patients with ESRD (eGFR< 18 ml/mn/1.73m 2 ) were significantly lower than the IQs of sibling controls [57].…”

The comparison of cognitive function and risk of dementia in CKD patients under peritoneal dialysis and hemodialysis

“…[17,26] Therefore, Vanderlinden et al thought that the cut-off scores on dementia screening tools such as the 3MS and MMSE may not be sensitive enough to detect impairment in these populations. [23] Meanwhile, TMT-B test was also commonly used in the studies included. Compared to TMT-A test, the TMT-B adds additional executive cognitive load via mental shifting.…”

“…[21] However, the studies with respect to different dialysis modalities are both too scarce and insufficient to allow for modality-specific conclusions. Although there were several meta-analyses concerning this topic, [2,22,23] the studies included are not up-to-date and not comprehensive. In this systematic review and meta-analysis, we collected all the studies comparing the cognitive functions between HD and PD, concluding that PD might be superior in preserving the cognitive functions and decreasing the risk of dementia compared with HD.…”