A Study of Executive Function in Patients with Chronic Kidney Disease before and after a Single Session of Hemodialysis

Dose response of transcranial near infrared light stimulation on brain functional connectivity and cognition in older adults-A randomized comparison

Photobiomodulation, also called low-level light therapy, has been reported in animal studies to have an effect on brain activity and cognition. However, studies in humans regarding its effect on cognition and brain functional connectivity, and the required dose threshold for achieving the same have been very limited. We compared the effects of different doses of photobiomodulation (PBM) on cognition and resting state brain functional connectivity in 25 cognitively normal adults aged 55-70 years. They were randomized to a single session of the sham group, "low-dose" and "high-dose" groups receiving NIR light with transcranial fluence of 26 and 52 J/cm2 respectively, and intranasal fluence of 9 and 18 J/cm2 respectively. There was a significant increase in resting state functional connectivity of the left superior frontal gyrus (SFG) with the left planum temporale (PT), p = 0.0016, and with the left inferior frontal gyrus, pars triangularis, p = 0.0235 in the "high-dose" group only compared to the "sham" group. There was also a significant improvement in visual search and processing speed (p = 0.012) in the "high-dose" group. Replication of these findings in an adequately powered randomized sham-controlled study in healthy older adults can pave the way for clinical application of NIRL as a therapeutic modality in patients with Alzheimer's disease.

Exploring the impact of cognitive impairments on treatment compliance and quality of life in patients with Continuous Ambulatory Peritoneal Dialysis (CAPD)

The aim of this study is to investigate the impact of cognitive impairments on treatment compliance and quality of life in patients with Continuous Ambulatory Peritoneal Dialysis (CAPD). A cross-sectional study was conducted among patients with CAPD at the Department of Nephrology, Lianshui People's Hospital from October 2021 to May 2022. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA), and the End-Stage Renal Disease Adherence Questionnaire was used to evaluate treatment compliance. Quality of life was assessed using the SF-36 questionnaire. Scores from all the questionnaires and demographic data were recorded. A total of 98 patients were enrolled, and the prevalence of cognitive impairment among CAPD patients was 69.39% (MoCA score < 26). Patients were divided into 2 groups: one group with normal cognitive function (MoCA score ≥ 26) and the other with cognitive impairments. There were statistically significant differences in age, dialysis age, education, urea clearance index, history of high blood pressure, and diabetes between the 2 groups (all P < .05). Patients with cognitive impairments had lower compliance levels in terms of diet fluid restriction, medication therapeutic regimens, and dialysis regimen (all P < .05). Patients with cognitive impairments also had lower quality of life scores in the dimensions of physical function, general health, social function, emotional function, and mental health (all P < .05). Cognitive impairment appears to be common among CAPD patients and may adversely affect both their treatment adherence and overall quality of life. A more comprehensive understanding of the underlying mechanisms necessitates further study.

Visuospatial and Executive Dysfunction in Patients With Acute Kidney Injury, Chronic Kidney Disease, and Kidney Failure: A Multilevel Modeling Analysis

Background:

Neurocognitive impairment is a common finding across the spectrum of kidney disease and carries important consequences for quality of life. We previously demonstrated that robotic technology can identify neurocognitive impairments not readily detectable by traditional testing in patients with acute kidney injury (AKI) and chronic kidney disease (CKD).

Objective:

The present study aimed to assess whether these quantifiable deficits in neurocognition differ based on a diagnosis of AKI, CKD, or kidney failure.

Design:

This was a cross-sectional analysis of participants previously enrolled in an observational study.

Setting:

Patients were enrolled at a tertiary academic hospital, Kingston Health Sciences Centre, Kingston, ON, Canada.

Patients:

Adults with AKI, CKD, or kidney failure.

Measurements:

Each participant underwent robotic neurocognitive assessment using the Kinarm: an interactive robotic device that uses a series of behavioral tasks involving movement of the upper limbs to precisely quantify neurocognitive impairment across a variety of neurocognitive domains.

Methods:

Multilevel modeling was used to determine the effect of Kinarm task type, kidney diagnostic group (AKI vs CKD vs kidney failure), and the interaction between the two, on neurocognitive performance.

Results:

A total of 104 participants within 1 year of an AKI event or with CKD category G3-5 were enrolled. We found that across all of the kidney diagnostic groups, participants performed worst on the Kinarm tasks of Reverse Visually Guided Reaching (b = 0.64 [95% confidence interval = 0.42, 0.85]), Visually Guided Reaching (b = 0.28 [0.07, 0.49]), and Trail Making (b = 0.50 [0.28, 0.72]), relative to all other tasks. There were no significant differences in average performance across tasks based on kidney diagnostic group. However, diagnostic group and neurocognitive task type interacted to determine performance, such that patients with AKI performed worse than those with either CKD or kidney failure on the Reverse Visually Guided Reaching task.

Limitations:

Kinarm assessment was performed at a single time point, and the sample size itself was small, which may lead to the risk of a false-positive association despite the use of multilevel modeling. Our sample size also did not permit inclusion of the underlying etiology of kidney impairment as a covariate in our analyses, which may have also influenced neurocognitive function.

Conclusions:

In this study that utilized the Kinarm to assess neurocognitive function, patients with AKI demonstrated significantly worse neurocognitive functioning than patients with CKD or kidney failure on a task measuring executive function and visuomotor control.